WO2025078972A1

WO2025078972A1 - Three-port srs resource design

Info

Publication number: WO2025078972A1
Application number: PCT/IB2024/059877
Authority: WO
Inventors: Sven JACOBSSON; Andreas Nilsson; Robert Mark Harrison
Original assignee: Telefonaktiebolaget LM Ericsson AB
Current assignee: Telefonaktiebolaget LM Ericsson AB
Priority date: 2023-10-10
Filing date: 2024-10-09
Publication date: 2025-04-17
Anticipated expiration: 2026-04-10

Abstract

Systems and methods for three-port Sounding Reference Signal (SRS) resource design and provided herein. In some embodiments, a method performed by a User Equipment (UE) includes: receiving a configuration with a four-port SRS resource; receiving a control message to trigger/activate an SRS transmission; and transmitting three out of four SRS ports of 4-port SRS resource. In this way, 3-port SRS resource design and 3-port SRS transmission is enables, thus enabling three transmit chain Uplink transmission.

Description

THREE-PORT SRS RESOURCE DESIGN RELATED APPLICATIONS [0001] This application claims the benefit of provisional patent application serial number 63/589,127, filed October 10, 2023, the disclosure of which is hereby incorporated herein by reference in its entirety. TECHNICAL FIELD [0002] The present disclosure relates generally to Sounding Reference Signal (SRS) resource design. BACKGROUND [0003] Numerology [0004] In the time domain, NR DL and UL transmissions are organized into equally sized subframes of 1 ms each. A subframe is further divided into multiple slots of equal duration. The slot length depends on the numerology (i.e., on the SCS and the CP). For 15 kHz SCS, there is only one slot per subframe. In general, for 15 ∙ 2^{^} kHz SCS, where ^ ∈ {0,1,2,3,4} is the SCS configuration, there are 2^{^} slots per subframe.

slot consists of 14 symbols (unless extended CP is configured for which each slot consists of 12 symbols). [0005] In the frequency domain, a channel bandwidth is divided into RBs each corresponding to 12 contiguous subcarriers. One subcarrier during one symbol interval forms one RE, which is the smallest physical resource in NR. [0006] Carrier aggregation [0007] NR supports CA of up to 16 CCs. A UE capable of CA can transmit/receive on multiple CCs at the same time, where different CCs may be of different channel bandwidths and/or duplex schemes (i.e., TDD or FDD). In FR1 (i.e., for operating bands n1—n105), channel bandwidths up to 100 MHz are supported. In FR2 (i.e., for operating bands n257—n263), channel bandwidths up to 400 MHz are supported. 3GPP TS 3GPP TS 38.101-1 and 3GPP TS 38.101-2 lists operating bands supporting (contiguous and non-contiguous) intra-band CA and inter-band CA for FR1 and FR2, respectively. With intra-band CA, CCs are in the same operating band. With inter-band CA, CCs are in different operating bands. [0008] In NR specification, a CC is referred to as a cell. One of said cells is known as the PCell and is the cell that the UE initially connects to. After the UE is connected, one or multiple SCells can be additionally configured. Furthermore, said SCells can be dynamically (via MAC CE signaling) activated/deactivated. When CA is not configured, UE will transmit/receive only on the PCell. The number of cells need not be the same in the DL and UL. Typically, since there is often more DL traffic than UL traffic, there are more DL cells than UL cells. [0009] The RBs within a cell (across the channel bandwidth) are known as CRBs and are numbered starting from 0. The first subcarrier in CRB 0 is known as reference point A, which is signaled to the UE as part of SIB1. [0010] Bandwidth parts [0011] NR is designed to support very large channel bandwidths (up to 400 MHz), but not all UEs are capable of handling such large channel bandwidth. For this reason, a UE can operate in a contiguous subset of the CRBs within a cell. This subset is called a BWP. [0012] A UE can be configured with up to four DL BWPs and up to four UL BWPs per serving cell, where different numerologies can be configured for different BWPs. The starting position and bandwidth of a BWP is RRC configured. Only one DL and one UL BWP can be active at the same time per serving cell. For TDD, the active DL and UL BWP must share the same center frequency. For FDD, this is not required. In the DL, a UE does not expect to receive, e.g., PDCCH and/or PDSCH outside the active BWP. In the UL, a UE is not expected to transmit, e.g., PUCCH and/or PUCCH outside of the active BWP. [0013] The NW can switch active BWP, e.g., via DCI signaling. For example, DCI Format 1_1 (used for scheduling DL transmissions) and DCI Format 0_1 (used for scheduling UL transmissions) includes an up to 2-bit “BWP indicator” field for switching BWP for DL and UL transmissions, respectively. [0014] The RBs within a BWP are known as PRBs and are numbered starting from 0. When the NW schedules a DL or UL transmission, a set of VRBs, which are mapped to PRBs, are signaled. In the DL, interleaved and non-interleaved mapping is supported. In the UL, only non- interleaved mapping is supported, for which there is a one-to-mapping between VRBs and CRBs. In what follows, unless otherwise stated, it is assumed that a one-to-one mapping between VRBs and PRBs, and simply use RBs to refer to both VRBs and CRBs. [0015] SRS [0016] SRS is an UL RS, based on Zadoff-Chu sequences, used for providing CSI to the NW. The usage of SRS includes, e.g., deriving the appropriate transmission/reception beams and/or to perform link adaptation (i.e., setting the transmission rank and the MCS), and for determining PDSCH and PUSCH precoding matrices. [0017] SRS configuration [0018] The SRS is configured via RRC signaling, where parts of the configuration can be updated (for reduced latency) via MAC CE signaling. When configuring SRS transmissions, the gNB configures, through the SRS-Config IE, a list of SRS resources and a list of SRS resource sets (see below snippet of ASN from 3GPP TS 38.331 version 17.2.0): SRS-Config ::= SEQUENCE { srs-ResourceSetToReleaseList SEQUENCE (SIZE(1..maxNrofSRS-ResourceSets)) OF SRS-ResourceSetId OPTIONAL, -- Need N srs-ResourceSetToAddModList SEQUENCE (SIZE(1..maxNrofSRS-ResourceSets)) OF SRS-ResourceSet OPTIONAL, -- Need N srs-ResourceToReleaseList SEQUENCE (SIZE(1..maxNrofSRS-Resources)) OF SRS-ResourceId OPTIONAL, -- Need N srs-ResourceToAddModList SEQUENCE (SIZE(1..maxNrofSRS-Resources)) OF SRS-Resource OPTIONAL, -- Need N ... } [0019] SRS resource(s) will be transmitted as part of an SRS resource set, where each SRS resource set contains one or more SRS resources, and where all SRS resources in an SRS resource set must share the same time-domain behavior. [0020] NR supports configuration of up to 16 SRS resource sets and 64 SRS resources per BWP. Furthermore, NR supports periodic (p-SRS), semi-persistent (sp-SRS), or aperiodic (ap- SRS) SRS transmissions: [0021] Periodic (p-SRS): SRS resource sets and SRS resources are RRC configured. SRS resource configuration includes slot periodicity and offset, which determines SRS transmission occasions. [0022] Semi-persistent (sp-SRS): SRS resource sets and SRS resources are RRC configured. SRS resource configuration includes slot periodicity and offset, and SRS transmissions are activated/deactivated using MAC CE signaling. [0023] Aperiodic (ap-SRS): SRS resource sets and SRS resources are RRC configured. SRS resource set configuration includes slot offset, and SRS transmissions are dynamically triggered via 2-bit “SRS request” field in DCI. [0024] In short, the SRS resource-set configuration determines, e.g., SRS usage, PC parameters, and slot offset for ap-SRS. The SRS resource configuration determines, e.g., the SRS time-and-frequency allocation, the SRS sequence, the periodicity and offset for p-SRS/sp-SRS. [0025] SRS resource set configuration [0026] An SRS resource set is configured with the following in RRC (see ASN code in 3GPP TS 38.331 version 17.2.0): SRS-ResourceSet ::= SEQUENCE { srs-ResourceSetId SRS-ResourceSetId, srs-ResourceIdList SEQUENCE (SIZE(1..maxNrofSRS-ResourcesPerSet)) OF SRS-ResourceId OPTIONAL, -- Cond Setup resourceType CHOICE { aperiodic SEQUENCE { aperiodicSRS-ResourceTrigger INTEGER (1..maxNrofSRS-TriggerStates-1), csi-RS NZP-CSI-RS- ResourceId OPTIONAL, -- Cond NonCodebook slotOffset INTEGER (1..32) OPTIONAL, -- Need S ..., [[ aperiodicSRS-ResourceTriggerList SEQUENCE (SIZE(1..maxNrofSRS-TriggerStates-2)) OF INTEGER (1..maxNrofSRS-TriggerStates-1) OPTIONAL -- Need M ]] }, semi-persistent SEQUENCE { associatedCSI-RS NZP-CSI-RS- ResourceId OPTIONAL, -- Cond NonCodebook ... }, periodic SEQUENCE { associatedCSI-RS NZP-CSI-RS- ResourceId OPTIONAL, -- Cond NonCodebook ... } }, usage ENUMERATED {beamManagement, codebook, nonCodebook, antennaSwitching}, alpha Alpha OPTIONAL, -- Need S p0 INTEGER (-202..24) OPTIONAL, -- Cond Setup pathlossReferenceRS PathlossReferenceRS- Config OPTIONAL, -- Need M srs-PowerControlAdjustmentStates ENUMERATED { sameAsFci2, separateClosedLoop} OPTIONAL, -- Need S ..., [[ pathlossReferenceRSList-r16 SetupRelease { PathlossReferenceRSList-r16} OPTIONAL -- Need M ]], [[ usagePDC-r17 ENUMERATED {true} OPTIONAL, -- Need R availableSlotOffsetList-r17 SEQUENCE (SIZE(1..4)) OF AvailableSlotOffset-r17 OPTIONAL, -- Need R followUnifiedTCIstateSRS-r17 ENUMERATED {enabled} OPTIONAL -- Need R ]] } [0027] An SRS resource set is configurable with respect to, e.g., [0028] The resource type, which is configured by the higher-layer parameter resourceType determines whether the SRS resource set is periodic, semi-persistent, or aperiodic. For ap-SRS, the slot offset is configured by the higher-layer parameter slotOffset and sets the delay from the PDCCH trigger reception to the start of the SRS transmission. [0029] The resource usage, which is configured by the higher-layer parameter usage determines constraints and assumptions on the resource properties (see 3GPP TS 38.214 for further details). SRS resource sets can be configured with one of four different usages: antennaSwitching, codebook, nonCodebook, or beamManagement. - An SRS resource set that is configured with usage antennaSwitching is used for reciprocity-based DL precoding (i.e., used to sound the channel in the UL so that the gNB can use reciprocity to set a suitable DL precoders). The UE is expected to transmit one SRS port per UE antenna port. - An SRS resource set that is configured with usage codebook is used for CB-based UL transmission (i.e., used to sound the different UE antennas and help the gNB to determine/signal a suitable UL precoder, transmission rank, and MCS for PUSCH transmission). There are up to two SRS resources in an SRS resource set with usage codebook. How SRS ports are mapped to UE antenna ports is, however, up to UE implementation and not known to the gNB. - An SRS resource set that is configured with usage nonCodebook is used for NCB-based UL transmission. Specifically, the UE transmits one SRS resource per candidate beam (suitable candidate beams are determined by the UE based on CSI-RS measurements in the DL and, hence, reciprocity needs to hold). The gNB can then, by indicating a subset of these SRS resources, determine which UL beam(s) that the UE should apply for PUSCH transmission. One UL layer will be transmitted per indicated SRS resource. Note that how the UE maps SRS ports to antenna ports is up to UE implementation and not known to the gNB. - An SRS resource set that is configured with usage beamManagement is used (mainly for frequency bands above 6 GHz (i.e., for FR2)) to evaluate different UE analog beams (e.g., panels). The UE transmits one SRS resource per analog beam, and the gNB will perform an RSRP measurement per transmitted SRS resource and, in this way, determine a suitable UE beam that is reported to the UE. [0030] The associated CSI-RS (this configuration is only applicable for NCB-based UL transmission) for each of the possible resource types. - For ap-SRS, the associated CSI-RS resource is determined by the higher-layer parameter csi-RS. - For p-SRS/sp-SRS, the associated CSI-RS resource is determined by the higher-layer parameter associatedCSI-RS. [0031] The PC parameters, e.g., alpha and p0 are used for setting the SRS transmission power. SRS has its own UL PC scheme in NR (see 3GPP TS 38.213 for further details), which specifies how the UE should split the available output power between two or more SRS ports during one SRS transmit occasion (an SRS transmit occasion is a time window within a slot where SRS transmission is performed). [0032] In NR Rel-17, dynamic/available SRS slot offset indication for ap-SRS was introduced and is configured by the higher-layer parameter availableSlotOffsetList-r17, which lists (up to) 4 slot offsets measured from the legacy slot offset ^ configured by the higher-layer parameter slotOffset. The DCI triggering the ap-SRS includes a (up to) 2-bit “SRS offset indicator” which indicates a value ^ from the list of slot offsets. If the DCI is transmitted in slot ^, the ap-SRS is transmitted in the ^^th available slot after slot ^ + ^, where an available slot is a slot that fits all SRS resources in the SRS resource set and that satisfies UE capability on minimum timing requirement. [0033] SRS resource configuration [0034] Each SRS resource is configured with the following in RRC (see below ASN code from 3GPP TS 38.331 version 17.2.0): SRS-Resource ::= SEQUENCE { srs-ResourceId SRS-ResourceId, nrofSRS-Ports ENUMERATED {port1, ports2, ports4}, ptrs-PortIndex ENUMERATED {n0, n1 } OPTIONAL, -- Need R transmissionComb CHOICE { n2 SEQUENCE { combOffset-n2 INTEGER (0..1), cyclicShift-n2 INTEGER (0..7) }, n4 SEQUENCE { combOffset-n4 INTEGER (0..3), cyclicShift-n4 INTEGER (0..11) } }, resourceMapping SEQUENCE { startPosition INTEGER (0..5), nrofSymbols ENUMERATED {n1, n2, n4}, repetitionFactor ENUMERATED {n1, n2, n4} }, freqDomainPosition INTEGER (0..67), freqDomainShift INTEGER (0..268), freqHopping SEQUENCE { c-SRS INTEGER (0..63), b-SRS INTEGER (0..3), b-hop INTEGER (0..3) }, groupOrSequenceHopping ENUMERATED { neither, groupHopping, sequenceHopping }, resourceType CHOICE { aperiodic SEQUENCE { ... }, semi-persistent SEQUENCE { periodicityAndOffset-sp SRS- PeriodicityAndOffset, ... }, SEQUENCE {

periodicityAndOffset-p SRS- PeriodicityAndOffset, ... } }, sequenceId INTEGER (0..1023), spatialRelationInfo SRS- SpatialRelationInfo OPTIONAL, -- Need R ..., [[ resourceMapping-r16 SEQUENCE { startPosition-r16 INTEGER (0..13), nrofSymbols-r16 ENUMERATED {n1, n2, n4}, repetitionFactor-r16 ENUMERATED {n1, n2, n4} } OPTIONAL -- Need R ]], [[ spatialRelationInfo-PDC-r17 SetupRelease { SpatialRelationInfo-PDC-r17 } OPTIONAL, -- Need M resourceMapping-r17 SEQUENCE { startPosition-r17 INTEGER (0..13), nrofSymbols-r17 ENUMERATED {n1, n2, n4, n8, n10, n12, n14}, repetitionFactor-r17 ENUMERATED {n1, n2, n4, n5, n6, n7, n8, n10, n12, n14} } OPTIONAL, -- Need R partialFreqSounding-r17 SEQUENCE { startRBIndexFScaling-r17 CHOICE{ startRBIndexAndFreqScalingFactor2-r17 INTEGER (0..1), startRBIndexAndFreqScalingFactor4-r17 INTEGER (0..3) }, enableStartRBHopping-r17 ENUMERATED {enable} OPTIONAL -- Need R } OPTIONAL, -- Need R transmissionComb-n8-r17 SEQUENCE { combOffset-n8-r17 INTEGER (0..7), cyclicShift-n8-r17 INTEGER (0..5) } OPTIONAL, -- Need R srs-TCIState-r17 CHOICE { srs-UL-TCIState-r17 TCI-UL-State-Id- r17, srs-DLorJoint-TCIState-r17 TCI-StateId } OPTIONAL -- Need R ]] } [0035] An SRS resource is configurable with respect to, e.g., [0036] The number of SRS ports (1, 2, or 4), configured by the higher-layer parameter nrofSRS-Ports. [0037] The transmission comb, i.e., mapping to every 2^nd, 4^th, or 8^th (in NR Rel-17) subcarrier, configured by the higher-layer parameter transmissionComb, which includes: - The higher-layer parameter combOffset determines the comb offset(s), i.e., which subcarriers that should be used for the SRS resource. For four-port SRS resource it is possible for an SRS resource to occupy two comb offsets, with two SRS ports per SRS resource. Configuring different comb offsets over SRS resources enables multiplexing of multiple SRS resources on a same SRS bandwidth. - The higher-layer parameter cyclicShift determines the CS(s) for the SRS resource. For multi-port SRS resources, different SRS ports use different CSs, where the CSs are equidistantly spaced. Configuring different CSs over SRS resources enables multiplexing of multiple SRS resources on a same comb offset, but there is a limit on how many CSs that can be used per comb offset: 8 CSs for comb 2, 12 CSs for comb 4, and 6 CSs for comb 8. [0038] The time-domain position within a given slot, configured with the higher-layer parameter resourceMapping, which includes: - The time-domain start position that (in NR Rel-15) is limited to one of the last 6 symbols, configured by the higher-layer parameter startPosition. In NR Rel-16, the start position was extended to any of the symbols in a slot. - The number of symbols that (in NR Rel-15) can be set to 1, 2 or 4, configured by the higher-layer parameter nrofSymbols. In NR Rel-17, the number of symbols was extended to include 8, 10, 12, and 14. - The repetition factor that (in NR Rel-15) can be set to 1, 2 or 4, configured by the higher- layer parameter repetitionFactor. When the repetition factor is larger than 1, the same frequency resources are used multiple times across symbols, used to improve the coverage as this allows more energy to be collected by the receiver. The repetition factor must be integer divisible by the number of symbols. In NR Rel-17, the repetition factor was extended to include also 5, 6, 7, 8, 10, 12, and 14. [0039] The SRS frequency-hopping pattern, frequency-domain position, and frequency- domain position shift of an SRS resource (i.e., which part of the BWP that is occupied by the SRS resource) is set through the following: - The higher-layer parameter the freqHopping which contains parameters c-SRS, b-SRS, and b-hop which determines the SRS bandwidth (the smallest possible sounding bandwidth is 4 RBs): • c-SRS, which determines “configured bandwidth” (see Figure 1). • b-hop, which determines the “hopping bandwidth” (see Figure 1). • b-SRS, which determines the “per-hop bandwidth” (see Figure 1). - The higher-layer parameter freqDomainPosition, which determines the start of the SRS hopping bandwidth relative to the SRS configured bandwidth (see Figure 1). - The higher-layer parameter freqDomainShift, which determines the start of the SRS configured bandwidth relative to the start of the BWP (see Figure 1). [0040] The higher-layer parameter resourceType determines whether the SRS resource is periodic, semi-persistent, or aperiodic. For sp-SRS and p-SRS, the slot offset and periodicity is configured by the higher-layer parameter periodicityAndOffset. [0041] The higher-layer parameter sequenceId specifies how the SRS sequence is initialized. • The higher-layer parameter spatialRelationInfo configures the spatial relation for the SRS beam with respect to another RS (which could be another SRS, an SSB, or a CSI-RS). If an SRS resource has a spatial relation to another SRS resource, it should be transmitted using the same virtualization as for the other SRS resource. [0042] Figure 1 illustrates an example of how an SRS resource could be allocated in time and frequency within a slot in NR Rel-15/Rel-16/Rel-17 (note that semi-persistent/periodic SRS resources typically span several slots). In NR Rel-15, SRS can occupy up to 4 of the last 6 symbols in a slot. In NR Rel-16, SRS can occupy up to 4 of all symbols in a slot. In NR Rel-17, SRS can occupy up to 14 of all symbols in a slot. [0043] In NR Rel-17, SRS partial frequency sounding was introduced and is configured by the higher-layer parameter partialFreqSounding. When partial frequency sounding is configured, an SRS resource will span only a subset (one half or one quarter) of the SRS per-hop bandwidth, which subset of the sounding bandwidth is configurable and may vary over symbols). SRS partial frequency sounding can be combined with SRS repetition and SRS frequency hopping. [0044] SRS port mapping [0045] An SRS port is mapped to a subset of the subcarriers in the configured SRS bandwidth. Specifically, the frequency-domain starting position for SRS port ^_^ = 1000 + ^ can be written as f^ollows: ^_{(^^) ^ (^^) *+ ^,*-} _{^ = ^^^ ∙ ^^!"#$ + ^%& . +^(##^)$ + ^(##^)$ .} [0046] Here, ^_^ ^{^} _^

_$ and ^₍ ^{^} #^, #_^ ^* )- $ is the starting position for frequency hopping and partial frequency sounding, and ^_^!"#$ is the

frequency-domain shift. Furthermore, the port-specific comb offset ^^{(^ )} T_C ^{^} depends on the RRC- configured comb offset ^^. _TC as follows: ^^{. + 1 ⁄ 2 mod 1 if ^SRS = 4, ^ ∈ {1001, 1 } cs,max} ( ^{0 TC TC 3 TC ap ^ 003 , and ^SRS = 6} ^_^^) _{TC = /0^.TC + 1TC⁄ 23 mod 1TC ^} ^cs,max ^_.

[0047] Here, 1_TC is the comb, ^₆-₇ ^{^-} is the number of SRS ports, and ^_S ^cs R^, S ^max is the number of CSs per comb offset, which ^{cs,max cs,max}

the comb as follows: ^ = 8 if 1

^_SRS = if 1_%& = 4, and ^_S ^cs R^,m S^ax = 6 if 1_%& = 8.

2 and 4 single-port SRS resources (with varying comb offset) using comb 2 and 4, respectively. Here, SRS resource ^ is configured with comb offset ^. Figure 2 shows an example of how multiple SRS resources can be multiplexed onto a same set of RBs by configuring different comb offsets. [0049] The SRS base sequences (i.e., Zadoff-Chu sequences) are pairwise orthogonal under CSs. Utilizing this property, it is possible to multiplex multiple SRS ports on a same comb offset by using different CSs (and the same base sequence) for different SRS ports. For multi-port SRS resources, different SRS ports belonging to the same SRS resource will use a port-specific CS per SRS port. Specifically, the cyclic shift 9_^ for antenna port ^_^ is given by

9_^ = 2: ^{^cs,^} ^SRS ^_cs,max. S_RS [0050] Where ^_S ^cs R^{,^} S depends on the RRC-configured cyclic shift ^^c S^s R_S as follows:

^{ì ^cs,max} ^{^cs + SRS ⌊(^^ − 1000)⁄ 2 ⌋} ^{mod ^cs,max if ^SRS = 4 and cs,max} ^{ï? SRS SRS C SRS ap ^SRS = 6} ^{cs ^ap ⁄ 2} ^{^ ,^}

Here, the comb is 4 such that the number of CSs per comb offset is 12, the 4-port SRS resource 0 is configured with CS 0, the 2-port SRS resource 1 is configured with CS 2, the 1-port SRS resource 2 is configured with CS 5, and the 1-port SRS resource 3 is configured with CS 11. Figure 3 shows an example of how multiple SRS resources (each with one or more SRS ports) can be mapped onto a same comb offset by configuring different cyclic shifts. [0052] It is worth mentioning that there are drawbacks associated with using a large comb and/or occupying multiple CSs per comb offset: For frequency-selective channels, the orthogonality between the SRS sequences may lost if the delay spread is large. For 4-port SRS resources configured with comb 2 or 4, it is possible to spread SRS ports over to two different comb offsets (where two different pairs of CS are used over the two comb offsets) to increase robustness towards delay spread. For 4-port SRS resources configured with comb 8, two comb offsets must be used (where the same pair of CSs is used over the two comb offsets). Spreading ports over multiple comb offsets increases robustness towards delay spread. Figures 4A and 4B illustrate spreading CSs over two comb offsets for 4-port SRS resources configured with comb 4 (Figure 4A) and comb 8 (Figure 4B). In Figures 4A and 4B, examples of possible CS and comb offset allocation for a 4-port SRS resource configured with comb 4 (Figure 4A) and comb 8 (Figure 4B) are shown. [0053] SRS antenna switching [0054] For reciprocity-based DL precoding, SRS is used to obtain CSI in the UL. It is desirable for the NW to sound all UE antennas (where sounding an antenna implies that SRS is transmitted from that antenna) but costly to equip the UE with many Tx chains (UEs typically have more Rx chains than Tx chains). Therefore, NR supports SRS antenna switching for UEs equipped with more Rx chains than Tx chains. If a UE support antenna switching, it will report so by means of UE-capability signaling (see, e.g., Table 1). Table 1 SRS antenna-switching capabilities supported by the UE (copied from 3GPP TS 38.306). supportedSRS-TxPortSwitch supportedSRS-TxPortSwitch- v1610 t1r2 t1r1-t1r2 t1r4 t1r1-t1r2-t1r4 t2r4 t1r1-t1r2-t2r2-t2r4 t2r2 t1r1-t2r2 t4r4 t1r1-t2r2-t4r4 t1r4-t2r4 t1r1-t1r2-t2r2-t1r4-t2r4 [0055] The left column Table 1 lists UE capabilities for SRS antenna-switching that can be reported by a UE in NR Rel-15. For example, if a UE reports t1r2 it means that it has two antennas (it has two Rx chains) but can only transmit from one of those antennas at a time (it has one Tx chain). In this case, NW can configure 1T2R antenna switching with two one-port SRS resources in an SRS resource set with usage antennaSwitching. The two SRS resources must be configured in different OFDM symbols and separated, at least, by a guard period that depends on the SCS (see Clause 6.2.1.2 of 3GPP TS 38.214 for further details) such that both antennas can be sounded, with an antenna switch in between. [0056] In general, DTER SRS antenna switching can be configured for a UE with D Tx chains and E Rx chains. Figure 5 illustrates 1T2R (left), 2T4R (middle), and 4T8R (right) SRS antenna ^{switching. Figure 5 shows examples of DTER SRS antenna switching for UE architectures with} _{D = E/2 Tx chains and E Rx chains.} [0057] In NR Rel-16, additional UE capabilities for SRS antenna-switching were introduced, which are shown in the right column of Table 1. Here, UE can indicate support for sounding only a subset of Rx antennas, which can save UE power consumption and SRS overhead at the cost of reduced channel knowledge at the gNB. For example, the UE capability t1r1-t1r2 indicates that the gNB can configure one single-port SRS resource (no antenna switching) or two single-port SRS resources (same as for the capability t1r2 described above) per SRS resource set with usage antennaSwitching. [0058] In NR Rel-17, antenna switching was extended to up to 6 or 8 Rx ports, and 1, 2, or 4 Tx chains. UE can indicate support for antenna-switching configurations beyond 4 Rx via higher- layer parameter srs-AntennaSwitchingBeyond4RX-r17 (see 3GPP TS 38.306 for further details). [0059] SRS repetition and/or frequency hopping [0060] SRS coverage can be increased for an SRS resource through repetition and/or frequency hopping. An example of SRS frequency hopping is provided in Figure 6 which illustrates SRS transmission over four symbols in one UL slot with frequency hopping. Here, different parts of the SRS bandwidth are sounded in each of four different OFDM symbols, which means that SRS coverage improves (by four times compared to SRS transmission in a single symbol), at the cost of more symbols being used for SRS and a shorter sequence length per OFDM symbol. An example of SRS repetition is provided in Figure 6. Here, one SRS resource is repeated in four consecutive OFDM symbols, which means that SRS coverage improves (by four times compared SRS transmission in a single symbol) at the cost of more symbols being used for SRS and decreased SRS (multiplexing) capacity. [0061] Figure 7 illustrates SRS transmission over four symbols in one UL slot with repetition. Figure 8 illustrates SRS transmission over two adjacent UL slots using both frequency hopping and repetition. It is worth pointing out that SRS repetition and frequency hopping can be used together and, that for p-SRS/sp-SRS, the frequency-hopping pattern continues beyond the slot boundary. In Figure 8, a p-SRS resource (with periodicity one) is shown over two adjacent UL slots. Here, the frequency-hopping configuration is the same as in Figure 6, the repetition factor is 2, and the number of SRS symbols per slot is 4. For ap-SRS, on the other hand, all parts of the configured bandwidth must be sounded within a slot. SUMMARY [0062] Systems and methods for three-port Sounding Reference Signal (SRS) resource design and provided herein. In some embodiments, a method performed by a User Equipment (UE) includes: receiving a configuration with a four-port SRS resource; receiving a control message to trigger/activate an SRS transmission; and transmitting three out of four SRS ports of 4-port SRS resource. In this way, 3-port SRS resource design and 3-port SRS transmission is enables, thus enabling three transmit chain Uplink transmission. [0063] In some embodiments, the method also includes: reporting UE capability for transmitting three SRS ports. In some embodiments, the method also includes: being explicitly configured to transmit only three out of the four SRS ports. In some embodiments, being explicitly configured comprises: receiving an indication that one of the SRS ports is muted. In some embodiments, receiving the control message comprises: receiving a DCI to trigger SRS transmission. In some embodiments, receiving the control message comprises: receiving a MAC CE to activate SRS transmission. [0064] In some embodiments, the UE capability comprises: a new UE capability that explicitly informs the network that UE is capable of transmitting three SRS ports. In some embodiments, reporting the UE capability comprises: reporting a maximum number of SRS ports per SRS resource, ^₆-₇ ^{^-}. In some embodiments, if ^₆-₇ ^{^-} ≥ 3, the UE is capable of transmitting three SRS ports. [0065] In some embodiments, being explicitly configured to transmit only three out of the four SRS ports comprises: a new field is added to SRS-Config IE such that the UE can be configured with muting of 4-port SRS resource. In some embodiments, the new field is present if and only if the number of SRS ports in the SRS resource is four. [0066] In some embodiments, the UE does not transmit the first SRS port in the SRS resource. In some embodiments, the UE does not transmit the last SRS port in the SRS resource. In some embodiments, which SRS port to mute is configured. In some embodiments, the method also includes supporting three used Cyclic Shifts, CSs, per comb offset if configured with muting of 4- port SRS resource. [0067] In some embodiments, the method also includes: reporting capability of supporting three CSs per comb offset if configured with muting of 4-port SRS resource. In some embodiments, the method also includes: reporting capability of supporting uneven number of CSs per comb offset if configured with muting of 4-port SRS resource. In some embodiments, the method also includes: splitting transmit power G_-^-,H,I,J linearly over the three SRS ports, such that the total SRS power is G_-^-,H,I,J. In some embodiments, a 3-port SRS resource maps all SRS ports onto a single comb offset and where the mapping is such that SRS ports are equidistantly spaced. In some embodiments, SRS ports in a 3-port SRS resource are mapped to CSs and comb offsets in such a way that two SRS ports is mapped to a first comb offset and one SRS port is mapped to a second offset. BRIEF DESCRIPTION OF THE DRAWINGS [0068] The accompanying drawing figures incorporated in and forming a part of this specification illustrate several aspects of the disclosure, and together with the description serve to explain the principles of the disclosure. [0069] Figure 1 illustrates an example of how an SRS resource could be allocated in time and frequency within a slot in NR Rel-15/Rel-16/Rel-17; [0070] Figure 2 illustrates multiplexing 2 and 4 single-port SRS resources (with varying comb offset) using comb 2 and 4, respectively; [0071] Figure 3 illustrates multiplexing of SRS resources on a same comb offset; [0072] Figures 4A and 4B illustrate examples of possible CS and comb offset allocation for a 4-port SRS resource configured with comb 4 and comb 8; [0073] Figure 5 illustrates 1T2R (left), 2T4R (middle), and 4T8R (right) SRS antenna switching; [0074] Figure 6 which illustrates SRS transmission over four symbols in one UL slot with frequency hopping; [0075] Figure 7 illustrates SRS transmission over four symbols in one UL slot with repetition; [0076] Figure 8 illustrates SRS transmission over two adjacent UL slots using both frequency hopping and repetition; [0077] Figure 9 illustrates a flowchart of transmitting 3 SRS ports via muting of 4-port SRS resource; [0078] Figure 10 illustrates muting of SRS ports for 4-port SRS resources configured with comb 4 where all CSs are on a same comb offset; [0079] Figures 11A and 11B illustrate muting of SRS ports for 4-port SRS resources configured with comb 4 and comb 8 where CSs are spread over two comb offsets; [0080] Figure 12 illustrates a flowchart of transmitting 3 SRS ports via 3-port SRS resource; [0081] Figure 13 illustrates a new 3-port SRS resources configured with comb 4 and comb 8 where CSs are evenly distributed over one comb offset; [0082] Figure 14 shows a flowchart related to embodiments in this section including a flowchart of transmitting 3 SRS ports via 2-port SRS resource and 1-port SRS resource; [0083] Figure 15 shows an example of a communication system 1500 in accordance with some embodiments; [0084] Figure 16 shows a UE in accordance with some embodiments; [0085] Figure 17 shows a network node in accordance with some embodiments; [0086] Figure 18 is a block diagram of a host, which may be an embodiment of the host 1516 of Figure 15, in accordance with various aspects described herein; [0087] Figure 19 is a block diagram illustrating a virtualization environment in which functions implemented by some embodiments may be virtualized; and [0088] Figure 20 shows a communication diagram of a host communicating via a network node with a UE over a partially wireless connection in accordance with some embodiments. DETAILED DESCRIPTION [0089] The embodiments set forth below represent information to enable those skilled in the art to practice the embodiments and illustrate the best mode of practicing the embodiments. Upon reading the following description in light of the accompanying drawing figures, those skilled in the art will understand the concepts of the disclosure and will recognize applications of these concepts not particularly addressed herein. It should be understood that these concepts and applications fall within the scope of the disclosure. [0090] Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art. [0091] There currently exist certain challenge(s). Legacy NR (i.e., up to Rel-18), specification supports UL transmission for 1, 2, 4, or 8 (in NR Rel-18) Tx chains. In practice, however, commercial UEs (e.g., smartphones) are restricted to 1—2 Tx chains due to factors such as PA cost and power consumption, and the limited size of commercial smartphones. [0092] Recently, CPE devices (targeting FWA deployments) supporting 3 Tx chains (e.g., MediaTek T830 CPE platform) have started to appear on the market. During recent trials [1, 2], record-setting UL throughputs have been achieved for such devices via UL CA, where 1 Tx on a 2.1GHz FDD band was combined with 2 Tx a 3.5GHz TDD band (see, e.g., Ericsson, MediaTek reach new technology milestone for the Fixed Wireless Access market (https://www.ericsson.com/en/news/2023/7/ericsson-mediatek-reach-new-tech-milestone-for- fwa-market) and Samsung Electronics and MediaTek Achieve Innovative 5G Uplink Breakthrough With Three Transmit Antennas (https://news.samsung.com/global/samsung- electronics-and-mediatek-achieve-innovative-5g-uplink-breakthrough-with-three-transmit- antennas)). For NR to support such devices, during the RAN#101 plenary meeting, it was agreed that there will be a NR Rel-18 RAN4 work item on supporting 3 Tx UL transmission over two bands (see, e.g., RP-21719, OPPO, WID revision for Core part 4Rx handheld UE for low NR bands (1GHz) and/or 3Tx for NR inter-band UL Carrier Aggregation (CA) and EN-DC, September 2023). However, 3 Tx UL transmission in a same band will not be supported in NR Rel-18. For this reason, 3 Tx UL transmission in a same cell has been proposed as a potential RAN1 work item in NR Rel-19 (see, e.g., RP-232612, AT&T, Moderator's summary for REL-19 RAN1 topic MIMO Evolution, September 2023), with strong support from, in particular, chipset/device vendors and operators. [0093] Legacy NR (i.e., up to Rel-18), does not support 3 Tx UL transmission in the same cell. For example, as explained herein, an SRS resource only can be configured with 1, 2, 4, or 8 SRS ports, a TPMI field can only indicate a precoder over 1, 2, 4 or 8 SRS ports, and an SRI field can only indicate up to 1, 2, 4 or 8 SRS resources. [0094] Certain aspects of the disclosure and their embodiments may provide solutions to these or other challenges. Some embodiments of the current disclosure describe three different solutions (and corresponding detailed embodiments) to introduce a 3-port SRS resource: • Blanking (muting of SRS port) of 4-port SRS resource, • Introduction of a new 3-port SRS resource, or • Combining two SRS resources, where a first SRS resource is configured with 2 SRS ports and a second SRS resource is configured with 1 SRS port. [0095] Certain embodiments may provide one or more of the following technical advantage(s). [0096] Three SRS ports via blanking of 4-port SRS resource [0097] In a first set of embodiments, UE is configured with 4-port SRS resource but configured to transmit only three out of said four SRS ports (one of the SRS ports is ‘blanked’/’muted’). Figure 9 illustrates a flowchart of transmitting 3 SRS ports via muting of 4- port SRS resource. Figure 9 shows a flowchart related to embodiments in this section. [0098] In Step 1, the UE reports to the NW a new UE capability for transmitting 3 SRS ports (using 3 Tx chains). [0099] In one embodiment, the new UE capability explicitly informs the NW that UE is capable of transmitting three SRS ports. [0100] In another embodiment, UE reports a maximum number of SRS ports per SRS resource, ^₆-₇ ^{^-}, and where it is understood that if ^₆-₇ ^{^-} ≥ 3, UE is capable of transmitting 3 SRS ports (note that, in legacy NR, there is UE capability for supporting a maximum number of SRS ports per SRS resource and where, e.g., ^₆-₇ ^{^-} = 4 implies that UE support 1, 2 or 4 SRS ports, but not 3 SRS ports). [0101] In Step 2, NW configures (in RRC) UE with 4-port SRS resource with usage ‘antennaSwitching’ (for reciprocity-based DL precoding) or ‘codebook’ for CB-based UL precoding. [0102] In Step 3, NW explicitly configures UE to transmit only 3 out of 4 SRS ports. Such explicit configuration is needed, e.g., if UE supports both 3 and >3 SRS ports but NW want to configure only 3 SRS ports (e.g., if SRS capacity is limited). [0103] In one embodiment (explicit configuration), a new field is added to SRS-Config IE (see example ASN below) such that NW can configure UE with blanking of 4-port SRS resource. In a related embodiment, this field is present if and only if the number of SRS ports in the SRS resource is 4. SRS-Resource ::= SEQUENCE { … nrofSRS-Ports ENUMERATED {port1, ports2, ports4}, … blanked-SRS-Port-r19 ENUMERATED {enable} OPTIONAL -- Cond ports4 ]] } [0104] In an alternate embodiment (implicit configuration), if UE has indicated capability for 3-port SRS resource (in Step 1), it is understood (by both NW and UE) that UE will transmit only 3 out of the 4 ports if NW configures UE with 4-port SRS resource. [0105] In Step 4, if the SRS resource is an ap-SRS, NW triggers 3-port SRS transmission via DCI, or, if the SRS resource is a sp-SRS, NW activates/deactivates 3-port SRS transmission via MAC CE. If the SRS resource is a p-SRS, Step 4 is not needed. [0106] In Step 5, UE transmits 3 out of the 4 SRS ports of a 4-port SRS resource. [0107] In one embodiment, UE does not transmit the first SRS port in the SRS resource (i.e., the SRS port with lowest port index: 1000). In an alternate embodiment, the UE does not transmit the last SRS port in the SRS resource (i.e., the SRS port with lowest port index: 1003). In an alternate embodiment, which SRS port to ‘blank’/‘mute’ can be configured by the NW (see example ASN below). SRS-Resource ::= SEQUENCE { … nrofSRS-Ports ENUMERATED {port1, ports2, ports4}, … blanked-SRS-Port-r19 ENUMERATED {blank1, blank2, blank3, blank4} OPTIONAL -- Cond ports4 ]] } [0108] Recall from Section 2.2.5 that SRS ports in a 4-port SRS resource can be mapped to CSs on 1 (for comb 2 and 4) or 2 (for comb 2, 4, or 8) comb offsets. [0109] Figure 10 illustrates muting of SRS ports for 4-port SRS resources configured with comb 4 where all CSs are on a same comb offset. In Figure 10, an example is shown of muting of a 4-port SRS resource configured with comb 4 (such that there are 12 CSs per comb offset) for which all 4 CSs are on a same comb offset and where the last SRS port (SRS port 1003) is muted such that there are 3 used CSs on one comb offset. [0110] In one embodiment, 3 Tx UE must support 3 used CSs per comb offset if configured with muting of 4-port SRS resource. [0111] Since new (i.e., not supported in legacy NR) number of used CS per comb offset may not be desired by UE/chipset vendors (there may be new RAN4 tests associated with such new number of used CS per comb offset), in one embodiment, UE may optionally report capability of supporting 3 CSs per comb offset if configured with muting of 4-port SRS resource. In an alternate embodiment, UE is not expected to be configured with 4 (3 after blanking) CSs per comb offset if blanking of 4-port SRS resource is configured. [0112] Figures 11A and 11B illustrate muting of SRS ports for 4-port SRS resources configured with comb 4 (Figure 11A) and comb 8 (Figure 11B) where CSs are spread over two comb offsets. In Figure 11A, an example is shown of muting of a 4-port SRS resource configured with comb 4 (such that there are 12 CSs per comb offset) for which the 4 CSs are spread over two comb offset and where the last SRS port (SRS port 1003) is muted. In Figure 11B, a similar example is shown of muting of a 4-port SRS resource configured with comb 8 (such that there are 6 CSs per comb offset). In this case, there are 2 used CSs on a first comb offset and 1 used CS on a second comb offset, which leads to either different power per subcarrier (if power is distributed evenly over SRS ports) or different power per SRS ports (if power is distributed evenly over subcarriers). [0113] Since there may be cons with using different SRS power per subcarrier or different SRS power per SRS port, in one embodiment, UE may optionally report capability of supporting uneven number of CSs per comb offset if configured with muting of 4-port SRS resource. In an alternate embodiment, UE is not expected to be configured with uneven number of CSs per comb offset if blanking of 4-port SRS resource is configured. [0114] In a related embodiment, comb 8 (for which the 4 SRS ports must be spread over multiple comb offsets, which is an optional configuration for comb 2 and 4) cannot be configured at the same time as muting of a 4-port SRS resource (UE is not expected be configured with muting and comb 8 at the same time). [0115] In existing specification for SRS power control, it is stated that UE splits the “transmit power G_-^-,H,I,J on active UL BWP K of carrier L of serving cell M equally across the configured antenna ports for SRS”. [0116] For blanking of 4-port SRS resource, it is unclear what is the configured number of antenna ports (e.g., 3 or 4): •^{In one embodiment, for a muted 4-port SRS resource, the UE splits transmit power} G_{-^-,H,I,J linearly over 3 SRS ports, such that the total SRS power is G-^-,H,I,J.} •^{In one embodiment, for a muted 4-port SRS resource, the UE splits transmit power} G_{-^-,H,I,J linearly over 4 SRS ports, such that the total SRS power is 0.75 ∙ G-^-,H,I,J.} • In one embodiment, for a muted 4-port SRS resource configured to map SRS ports to two different comb offsets, UE splits half of the transmit over the 2 SRS ports mapped to a first comb offset and half of the transmit power over the 1 SRS port mapped to a second comb offset, such that the total SRS power is G_-^-,H,I,J. [0117] In Step 5, NW receives 3 out of 4 SRS ports. In other words, NW is expected to measure the channel (compute a channel estimate) only for 3 out of the 4 SRS ports in a 4-port SRS resource. [0118] 3 SRS ports in new 3-port SRS resource [0119] There are some drawbacks with blanking an SRS port for 4-port SRS resource: • If the 3 out of 4 SRS ports are mapped to the same comb offset (which is not possible for comb 8), SRS ports are non-equidistant, which leads to non-optimal robustness towards delay spread • If the 3 out of 4 SRS ports are spread over two comb offsets, the SRS power per subcarrier or the SRS power per port is not constant. [0120] Therefore, in a second set of embodiments, a new 3-port SRS resource design is proposed. Figure 12 illustrates a flowchart of transmitting 3 SRS ports via 3-port SRS resource. Figure 12 shows a flowchart related to embodiments in this section. [0121] In one embodiment, a new field for configuring the number of SRS ports is added in SRS-Config IE such that NW can configure 3-port SRS resource. When this new field is configured, UE shall ignore the value of the field nrofSRS-ports. SRS-Resource ::= SEQUENCE { … nrofSRS-Ports ENUMERATED {port1, ports2, ports4}, … nrof-SRS-Ports-r19 ENUMERATED {port1, ports2, ports3, ports4, ports8} OPTIONAL -- Need R ]] } [0122] Figure 13 illustrates a new 3-port SRS resources configured with comb 4 (left part of the figure) and comb 8 (right part of the figure) where CSs are evenly distributed over one comb offset. In one embodiment, a 3-port SRS resource maps all SRS ports onto a single comb offset (i.e., 3 ports per comb offset) and where the mapping is such that SRS ports are equidistantly spaced (see Figure 13), i.e., • Mapping is such that CS 0 + M, 4 + M, and 8 + M, where M ∈ {0, 1, 2, 3} are occupied for an SRS resource configured with comb 4. • Mapping is such that CS 0 + M, 2 + M, and 4 + M, where M ∈ {0, 1} are occupied for an SRS resource configured with comb 8. [0123] In one embodiment, the above parameter M is RRC configured by new higher-layer parameter, e.g., combOffset-r19 (which replaces combOffset) and the above listed values of M for combs 4 and 8 are the only possible/supported values for this new higher-layer parameter. [0124] In one embodiment, since there are 8 CSs for comb 2, and since 8 is not integer divisible by 3, a 3-port SRS resource cannot be configured with comb 2 (UE is not expected be configured with 3 SRS ports and comb 2 at the same time). [0125] In one embodiment, 3 SRS ports is mapped to a single comb offset in such a way that CSs are not equidistantly separated (e.g., CS 0 + M, 3 + M, 6 + M for comb 2). [0126] In one embodiment, despite the aforementioned drawbacks, SRS ports in a 3-port SRS resource are mapped to CSs and comb offsets in such a way that 2 SRS ports are mapped to a first comb offset and 1 SRS port is mapped to a second offset. [0127] In one embodiment, for comb 4 and/or 8, SRS ports in a 3-port SRS resource are mapped to three different comb offsets. [0128] 3 SRS ports via 2-port SRS resource and 1-port SRS resource [0129] In a third set of embodiments, to minimize specification impact, 3 SRS ports are transmitted over two SRS resources, where a first SRS resource is configured with 2 SRS ports and a second SRS resource is configured with 1 SRS port. Both SRS resources belong to a same SRS resource set (e.g., with usage ‘antennaSwitching’ or ‘codebook’). Figure 14 shows a flowchart related to embodiments in this section including a flowchart of transmitting 3 SRS ports via 2-port SRS resource and 1-port SRS resource. [0130] In a preferred embodiment, the 2-port SRS resource and 1-port SRS resource must be configured in the same OFDM symbol(s). In this way, the UE splits the power over 2-port SRS resource and 1-port SRS resource in such a way that the power per SRS port is split equally over the 3 SRS ports (i.e., 2/3 and 1/3 third of the SRS power will be used for the 2-port SRS resource and the 1-port SRS resource, respectively). [0131] In another embodiment, the 2-port SRS resource and 1-port SRS resource can be configured in non-overlapping OFDM symbols. In a further embodiment, the SRS power in the OFDM symbol containing the 1-port SRS resource half of the SRS power in the OFDM symbol containing the 2-port SRS resource (such that the power per SRS ports is the same over the 3 SRS ports). [0132] In one embodiment, UE is required to transmit the two SRS resources such that coherence is maintained over, at least, a subset of the three SRS ports: • In one embodiment, if SRS ports are in an SRS resource set with usage set to codebook, and if UE has reported capability for partially-coherent precoding, UE is expected to maintain coherence when transmitting PUSCH over the two SRS ports in the 2-port SRS resource (it is not required that these 2 SRS ports maintain coherence with the SRS port in the 1-port SRS resource). • In one embodiment, if SRS ports are in an SRS resource set with usage set to codebook, and if UE has reported capability for fully-coherent precoding, UE is expected to maintain coherence when transmitting PUSCH over the three SRS ports in the 2-port SRS resource and the SRS port in the 1-port SRS resource. In other words, UE is expected to maintain coherence over multiple SRS resources in the same SRS resource set. [0133] In one extension to these sets of embodiments, instead of combining two SRS resources, where a first SRS resource is configured with 2 SRS ports and a second SRS resource is configured with 1 SRS port, in one embodiment, three 1-port SRS resources are combined. [0134] Figure 15 shows an example of a communication system 1500 in accordance with some embodiments. [0135] In the example, the communication system 1500 includes a telecommunication network 1502 that includes an access network 1504, such as a Radio Access Network (RAN), and a core network 1506, which includes one or more core network nodes 1508. The access network 1504 includes one or more access network nodes, such as network nodes 1510A and 1510B (one or more of which may be generally referred to as network nodes 1510), or any other similar Third Generation Partnership Project (3GPP) access nodes or non-3GPP Access Points (APs). Moreover, as will be appreciated by those of skill in the art, a network node is not necessarily limited to an implementation in which a radio portion and a baseband portion are supplied and integrated by a single vendor. Thus, it will be understood that network nodes include disaggregated implementations or portions thereof. For example, in some embodiments, the telecommunication network 1502 includes one or more Open-RAN (ORAN) network nodes. An ORAN network node is a node in the telecommunication network 1502 that supports an ORAN specification (e.g., a specification published by the O-RAN Alliance, or any similar organization) and may operate alone or together with other nodes to implement one or more functionalities of any node in the telecommunication network 1502, including one or more network nodes 1510 and/or core network nodes 1508. [0136] Examples of an ORAN network node include an Open Radio Unit (O-RU), an Open Distributed Unit (O-DU), an Open Central Unit (O-CU), including an O-CU Control Plane (O- CU-CP) or an O-CU User Plane (O-CU-UP), a RAN intelligent controller (near-real time or non- real time) hosting software or software plug-ins, such as a near-real time control application (e.g., xApp) or a non-real time control application (e.g., rApp), or any combination thereof (the adjective “open” designating support of an ORAN specification). The network node may support a specification by, for example, supporting an interface defined by the ORAN specification, such as an A1, F1, W1, E1, E2, X2, Xn interface, an open fronthaul user plane interface, or an open fronthaul management plane interface. Moreover, an ORAN access node may be a logical node in a physical node. Furthermore, an ORAN network node may be implemented in a virtualization environment (described further below) in which one or more network functions are virtualized. For example, the virtualization environment may include an O-Cloud computing platform orchestrated by a Service Management and Orchestration Framework via an O-2 interface defined by the O-RAN Alliance or comparable technologies. The network nodes 1510 facilitate direct or indirect connection of User Equipment (UE), such as by connecting UEs 1512A, 1512B, 1512C, and 1512D (one or more of which may be generally referred to as UEs 1512) to the core network 1506 over one or more wireless connections. [0137] Example wireless communications over a wireless connection include transmitting and/or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and/or other types of signals suitable for conveying information without the use of wires, cables, or other material conductors. Moreover, in different embodiments, the communication system 1500 may include any number of wired or wireless networks, network nodes, UEs, and/or any other components or systems that may facilitate or participate in the communication of data and/or signals whether via wired or wireless connections. The communication system 1500 may include and/or interface with any type of communication, telecommunication, data, cellular, radio network, and/or other similar type of system. [0138] The UEs 1512 may be any of a wide variety of communication devices, including wireless devices arranged, configured, and/or operable to communicate wirelessly with the network nodes 1510 and other communication devices. Similarly, the network nodes 1510 are arranged, capable, configured, and/or operable to communicate directly or indirectly with the UEs 1512 and/or with other network nodes or equipment in the telecommunication network 1502 to enable and/or provide network access, such as wireless network access, and/or to perform other functions, such as administration in the telecommunication network 1502. [0139] In the depicted example, the core network 1506 connects the network nodes 1510 to one or more hosts, such as host 1516. These connections may be direct or indirect via one or more intermediary networks or devices. In other examples, network nodes may be directly coupled to hosts. The core network 1506 includes one more core network nodes (e.g., core network node 1508) that are structured with hardware and software components. Features of these components may be substantially similar to those described with respect to the UEs, network nodes, and/or hosts, such that the descriptions thereof are generally applicable to the corresponding components of the core network node 1508. Example core network nodes include functions of one or more of a Mobile Switching Center (MSC), Mobility Management Entity (MME), Home Subscriber Server (HSS), Access and Mobility Management Function (AMF), Session Management Function (SMF), Authentication Server Function (AUSF), Subscription Identifier De-Concealing Function (SIDF), Unified Data Management (UDM), Security Edge Protection Proxy (SEPP), Network Exposure Function (NEF), and/or a User Plane Function (UPF). [0140] The host 1516 may be under the ownership or control of a service provider other than an operator or provider of the access network 1504 and/or the telecommunication network 1502, and may be operated by the service provider or on behalf of the service provider. The host 1516 may host a variety of applications to provide one or more service. Examples of such applications include live and pre-recorded audio/video content, data collection services such as retrieving and compiling data on various ambient conditions detected by a plurality of UEs, analytics functionality, social media, functions for controlling or otherwise interacting with remote devices, functions for an alarm and surveillance center, or any other such function performed by a server. [0141] As a whole, the communication system 1500 of Figure 15 enables connectivity between the UEs, network nodes, and hosts. In that sense, the communication system 1500 may be configured to operate according to predefined rules or procedures, such as specific standards that include, but are not limited to: Global System for Mobile Communications (GSM); Universal Mobile Telecommunications System (UMTS); Long Term Evolution (LTE), and/or other suitable Second, Third, Fourth, or Fifth Generation (2G, 3G, 4G, or 5G) standards, or any applicable future generation standard (e.g., Sixth Generation (6G)); Wireless Local Area Network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards (WiFi); and/or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z-Wave, Near Field Communication (NFC) ZigBee, LiFi, and/or any Low Power Wide Area Network (LPWAN) standards such as LoRa and Sigfox. [0142] In some examples, the telecommunication network 1502 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunication network 1502 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 1502. For example, the telecommunication network 1502 may provide Ultra Reliable Low Latency Communication (URLLC) services to some UEs, while providing enhanced Mobile Broadband (eMBB) services to other UEs, and/or massive Machine Type Communication (mMTC)/massive Internet of Things (IoT) services to yet further UEs. [0143] In some examples, the UEs 1512 are configured to transmit and/or receive information without direct human interaction. For instance, a UE may be designed to transmit information to the access network 1504 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 1504. Additionally, a UE may be configured for operating in single- or multi-Radio Access Technology (RAT) or multi-standard mode. For example, a UE may operate with any one or combination of WiFi, New Radio (NR), and LTE, i.e. being configured for Multi-Radio Dual Connectivity (MR-DC), such as Evolved UMTS Terrestrial RAN (E-UTRAN) NR - Dual Connectivity (EN-DC). [0144] In the example, a hub 1514 communicates with the access network 1504 to facilitate indirect communication between one or more UEs (e.g., UE 1512C and/or 1512D) and network nodes (e.g., network node 1510B). In some examples, the hub 1514 may be a controller, router, content source and analytics, or any of the other communication devices described herein regarding UEs. For example, the hub 1514 may be a broadband router enabling access to the core network 1506 for the UEs. As another example, the hub 1514 may be a controller that sends commands or instructions to one or more actuators in the UEs. Commands or instructions may be received from the UEs, network nodes 1510, or by executable code, script, process, or other instructions in the hub 1514. As another example, the hub 1514 may be a data collector that acts as temporary storage for UE data and, in some embodiments, may perform analysis or other processing of the data. As another example, the hub 1514 may be a content source. For example, for a UE that is a Virtual Reality (VR) headset, display, loudspeaker or other media delivery device, the hub 1514 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 1514 then provides to the UE either directly, after performing local processing, and/or after adding additional local content. In still another example, the hub 1514 acts as a proxy server or orchestrator for the UEs, in particular if one or more of the UEs are low energy IoT devices. [0145] The hub 1514 may have a constant/persistent or intermittent connection to the network node 1510B. The hub 1514 may also allow for a different communication scheme and/or schedule between the hub 1514 and UEs (e.g., UE 1512C and/or 1512D), and between the hub 1514 and the core network 1506. In other examples, the hub 1514 is connected to the core network 1506 and/or one or more UEs via a wired connection. Moreover, the hub 1514 may be configured to connect to a Machine-to-Machine (M2M) service provider over the access network 1504 and/or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 1510 while still connected via the hub 1514 via a wired or wireless connection. In some embodiments, the hub 1514 may be a dedicated hub – that is, a hub whose primary function is to route communications to/from the UEs from/to the network node 1510B. In other embodiments, the hub 1514 may be a non-dedicated hub – that is, a device which is capable of operating to route communications between the UEs and the network node 1510B, but which is additionally capable of operating as a communication start and/or end point for certain data channels. [0146] Figure 16 shows a UE 1600 in accordance with some embodiments. As used herein, a UE refers to a device capable, configured, arranged, and/or operable to communicate wirelessly with network nodes and/or other UEs. Examples of a UE include, but are not limited to, a smart phone, mobile phone, cell phone, Voice over Internet Protocol (VoIP) phone, wireless local loop phone, desktop computer, Personal Digital Assistant (PDA), wireless camera, gaming console or device, music storage device, playback appliance, wearable terminal device, wireless endpoint, mobile station, tablet, laptop, Laptop Embedded Equipment (LEE), Laptop Mounted Equipment (LME), smart device, wireless Customer Premise Equipment (CPE), vehicle, vehicle-mounted or vehicle embedded/integrated wireless device, etc. Other examples include any UE identified by the 3GPP, including a Narrowband Internet of Things (NB-IoT) UE, a Machine Type Communication (MTC) UE, and/or an enhanced MTC (eMTC) UE. [0147] A UE may support Device-to-Device (D2D) communication, for example by implementing a 3GPP standard for sidelink communication, Dedicated Short-Range Communication (DSRC), Vehicle-to-Vehicle (V2V), Vehicle-to-Infrastructure (V2I), or Vehicle- to-Everything (V2X). In other examples, a UE may not necessarily have a user in the sense of a human user who owns and/or operates the relevant device. Instead, a UE may represent a device that is intended for sale to, or operation by, a human user but which may not, or which may not initially, be associated with a specific human user (e.g., a smart sprinkler controller). Alternatively, a UE may represent a device that is not intended for sale to, or operation by, an end user but which may be associated with or operated for the benefit of a user (e.g., a smart power meter). [0148] The UE 1600 includes processing circuitry 1602 that is operatively coupled via a bus 1604 to an input/output interface 1606, a power source 1608, memory 1610, a communication interface 1612, and/or any other component, or any combination thereof. Certain UEs may utilize all or a subset of the components shown in Figure 16. The level of integration between the components may vary from one UE to another UE. Further, certain UEs may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc. [0149] The processing circuitry 1602 is configured to process instructions and data and may be configured to implement any sequential state machine operative to execute instructions stored as machine-readable computer programs in the memory 1610. The processing circuitry 1602 may be implemented as one or more hardware-implemented state machines (e.g., in discrete logic, Field Programmable Gate Arrays (FPGAs), Application Specific Integrated Circuits (ASICs), etc.); programmable logic together with appropriate firmware; one or more stored computer programs, general purpose processors, such as a microprocessor or Digital Signal Processor (DSP), together with appropriate software; or any combination of the above. For example, the processing circuitry 1602 may include multiple Central Processing Units (CPUs). [0150] In the example, the input/output interface 1606 may be configured to provide an interface or interfaces to an input device, output device, or one or more input and/or output devices. Examples of an output device include a speaker, a sound card, a video card, a display, a monitor, a printer, an actuator, an emitter, a smartcard, another output device, or any combination thereof. An input device may allow a user to capture information into the UE 1600. Examples of an input device include a touch-sensitive or presence-sensitive display, a camera (e.g., a digital camera, a digital video camera, a web camera, etc.), a microphone, a sensor, a mouse, a trackball, a directional pad, a trackpad, a scroll wheel, a smartcard, and the like. The presence-sensitive display may include a capacitive or resistive touch sensor to sense input from a user. A sensor may be, for instance, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, a biometric sensor, etc., or any combination thereof. An output device may use the same type of interface port as an input device. For example, a Universal Serial Bus (USB) port may be used to provide an input device and an output device. [0151] In some embodiments, the power source 1608 is structured as a battery or battery pack. Other types of power sources, such as an external power source (e.g., an electricity outlet), photovoltaic device, or power cell, may be used. The power source 1608 may further include power circuitry for delivering power from the power source 1608 itself, and/or an external power source, to the various parts of the UE 1600 via input circuitry or an interface such as an electrical power cable. Delivering power may be, for example, for charging of the power source 1608. Power circuitry may perform any formatting, converting, or other modification to the power from the power source 1608 to make the power suitable for the respective components of the UE 1600 to which power is supplied. [0152] The memory 1610 may be or be configured to include memory such as Random Access Memory (RAM), Read Only Memory (ROM), Programmable ROM (PROM), Erasable PROM (EPROM), Electrically EPROM (EEPROM), magnetic disks, optical disks, hard disks, removable cartridges, flash drives, and so forth. In one example, the memory 1610 includes one or more application programs 1614, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data 1616. The memory 1610 may store, for use by the UE 1600, any of a variety of various operating systems or combinations of operating systems. [0153] The memory 1610 may be configured to include a number of physical drive units, such as Redundant Array of Independent Disks (RAID), flash memory, USB flash drive, external hard disk drive, thumb drive, pen drive, key drive, High Density Digital Versatile Disc (HD-DVD) optical disc drive, internal hard disk drive, Blu-Ray optical disc drive, Holographic Digital Data Storage (HDDS) optical disc drive, external mini Dual In-line Memory Module (DIMM), Synchronous Dynamic RAM (SDRAM), external micro-DIMM SDRAM, smartcard memory such as a tamper resistant module in the form of a Universal Integrated Circuit Card (UICC) including one or more Subscriber Identity Modules (SIMs), such as a Universal SIM (USIM) and/or Internet Protocol Multimedia Services Identity Module (ISIM), other memory, or any combination thereof. The UICC may for example be an embedded UICC (eUICC), integrated UICC (iUICC) or a removable UICC commonly known as a ‘SIM card.’ The memory 1610 may allow the UE 1600 to access instructions, application programs, and the like stored on transitory or non-transitory memory media, to off-load data, or to upload data. An article of manufacture, such as one utilizing a communication system, may be tangibly embodied as or in the memory 1610, which may be or comprise a device-readable storage medium. [0154] The processing circuitry 1602 may be configured to communicate with an access network or other network using the communication interface 1612. The communication interface 1612 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna 1622. The communication interface 1612 may include one or more transceivers used to communicate, such as by communicating with one or more remote transceivers of another device capable of wireless communication (e.g., another UE or a network node in an access network). Each transceiver may include a transmitter 1618 and/or a receiver 1620 appropriate to provide network communications (e.g., optical, electrical, frequency allocations, and so forth). Moreover, the transmitter 1618 and receiver 1620 may be coupled to one or more antennas (e.g., the antenna 1622) and may share circuit components, software, or firmware, or alternatively be implemented separately. [0155] In the illustrated embodiment, communication functions of the communication interface 1612 may include cellular communication, WiFi communication, LPWAN communication, data communication, voice communication, multimedia communication, short- range communications such as Bluetooth, NFC, location-based communication such as the use of the Global Positioning System (GPS) to determine a location, another like communication function, or any combination thereof. Communications may be implemented according to one or more communication protocols and/or standards, such as IEEE 802.11, Code Division Multiplexing Access (CDMA), Wideband CDMA (WCDMA), GSM, LTE, NR, UMTS, WiMax, Ethernet, Transmission Control Protocol/Internet Protocol (TCP/IP), Synchronous Optical Networking (SONET), Asynchronous Transfer Mode (ATM), Quick User Datagram Protocol Internet Connection (QUIC), Hypertext Transfer Protocol (HTTP), and so forth. [0156] Regardless of the type of sensor, a UE may provide an output of data captured by its sensors, through its communication interface 1612, via a wireless connection to a network node. Data captured by sensors of a UE can be communicated through a wireless connection to a network node via another UE. The output may be periodic (e.g., once every 15 minutes if it reports the sensed temperature), random (e.g., to even out the load from reporting from several sensors), in response to a triggering event (e.g., when moisture is detected an alert is sent), in response to a request (e.g., a user initiated request), or a continuous stream (e.g., a live video feed of a patient). [0157] As another example, a UE comprises an actuator, a motor, or a switch related to a communication interface configured to receive wireless input from a network node via a wireless connection. In response to the received wireless input the states of the actuator, the motor, or the switch may change. For example, the UE may comprise a motor that adjusts the control surfaces or rotors of a drone in flight according to the received input or to a robotic arm performing a medical procedure according to the received input. [0158] A UE, when in the form of an IoT device, may be a device for use in one or more application domains, these domains comprising, but not limited to, city wearable technology, extended industrial application, and healthcare. Non-limiting examples of such an IoT device are a device which is or which is embedded in: a connected refrigerator or freezer, a television, a connected lighting device, an electricity meter, a robot vacuum cleaner, a voice controlled smart speaker, a home security camera, a motion detector, a thermostat, a smoke detector, a door/window sensor, a flood/moisture sensor, an electrical door lock, a connected doorbell, an air conditioning system like a heat pump, an autonomous vehicle, a surveillance system, a weather monitoring device, a vehicle parking monitoring device, an electric vehicle charging station, a smart watch, a fitness tracker, a head-mounted display for Augmented Reality (AR) or VR, a wearable for tactile augmentation or sensory enhancement, a water sprinkler, an animal- or item-tracking device, a sensor for monitoring a plant or animal, an industrial robot, an Unmanned Aerial Vehicle (UAV), and any kind of medical device, like a heart rate monitor or a remote controlled surgical robot. A UE in the form of an IoT device comprises circuitry and/or software in dependence of the intended application of the IoT device in addition to other components as described in relation to the UE 1600 shown in Figure 16. [0159] As yet another specific example, in an IoT scenario, a UE may represent a machine or other device that performs monitoring and/or measurements and transmits the results of such monitoring and/or measurements to another UE and/or a network node. The UE may in this case be an M2M device, which may in a 3GPP context be referred to as an MTC device. As one particular example, the UE may implement the 3GPP NB-IoT standard. In other scenarios, a UE may represent a vehicle, such as a car, a bus, a truck, a ship, an airplane, or other equipment that is capable of monitoring and/or reporting on its operational status or other functions associated with its operation. [0160] In practice, any number of UEs may be used together with respect to a single use case. For example, a first UE might be or be integrated in a drone and provide the drone’s speed information (obtained through a speed sensor) to a second UE that is a remote controller operating the drone. When the user makes changes from the remote controller, the first UE may adjust the throttle on the drone (e.g., by controlling an actuator) to increase or decrease the drone’s speed. The first and/or the second UE can also include more than one of the functionalities described above. For example, a UE might comprise the sensor and the actuator and handle communication of data for both the speed sensor and the actuators. [0161] Figure 17 shows a network node 1700 in accordance with some embodiments. As used herein, network node refers to equipment capable, configured, arranged, and/or operable to communicate directly or indirectly with a UE and/or with other network nodes or equipment in a telecommunication network. Examples of network nodes include, but are not limited to, APs (e.g., radio APs), Base Stations (BSs) (e.g., radio BSs, Node Bs, evolved Node Bs (eNBs), NR Node Bs (gNBs)), and O-RAN nodes or components of an O-RAN node (e.g., O-RU, O-DU, O-CU). [0162] Base stations may be categorized based on the amount of coverage they provide (or, stated differently, their transmit power level) and so, depending on the provided amount of coverage, may be referred to as femto base stations, pico base stations, micro base stations, or macro base stations. A base station may be a relay node or a relay donor node controlling a relay. A network node may also include one or more (or all) parts of a distributed radio base station such as centralized digital units, distributed units (e.g., in an O-RAN access node), and/or Remote Radio Units (RRUs), sometimes referred to as Remote Radio Heads (RRHs). Such RRUs may or may not be integrated with an antenna as an antenna integrated radio. Parts of a distributed radio base station may also be referred to as nodes in a Distributed Antenna System (DAS). [0163] Other examples of network nodes include multiple Transmission Point (multi-TRP) 5G access nodes, Multi-Standard Radio (MSR) equipment such as MSR BSs, network controllers such as Radio Network Controllers (RNCs) or BS Controllers (BSCs), Base Transceiver Stations (BTSs), transmission points, transmission nodes, Multi-Cell/Multicast Coordination Entities (MCEs), Operation and Maintenance (O&M) nodes, Operations Support System (OSS) nodes, Self-Organizing Network (SON) nodes, positioning nodes (e.g., Evolved Serving Mobile Location Centers (E-SMLCs)), and/or Minimization of Drive Tests (MDTs). [0164] The network node 1700 includes processing circuitry 1702, memory 1704, a communication interface 1706, and a power source 1708. The network node 1700 may be composed of multiple physically separate components (e.g., a NodeB component and an RNC component, or a BTS component and a BSC component, etc.), which may each have their own respective components. In certain scenarios in which the network node 1700 comprises multiple separate components (e.g., BTS and BSC components), one or more of the separate components may be shared among several network nodes. For example, a single RNC may control multiple NodeBs. In such a scenario, each unique NodeB and RNC pair may in some instances be considered a single separate network node. In some embodiments, the network node 1700 may be configured to support multiple RATs. In such embodiments, some components may be duplicated (e.g., separate memory 1704 for different RATs) and some components may be reused (e.g., a same antenna 1710 may be shared by different RATs). The network node 1700 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 1700, for example GSM, WCDMA, LTE, NR, WiFi, Zigbee, Z-wave, Long Range Wide Area Network (LoRaWAN), Radio Frequency Identification (RFID), or Bluetooth wireless technologies. These wireless technologies may be integrated into the same or different chip or set of chips and other components within the network node 1700. [0165] The processing circuitry 1702 may comprise a combination of one or more of a microprocessor, controller, microcontroller, CPU, DSP, ASIC, FPGA, or any other suitable computing device, resource, or combination of hardware, software, and/or encoded logic operable to provide, either alone or in conjunction with other network node 1700 components, such as the memory 1704, to provide network node 1700 functionality. [0166] In some embodiments, the processing circuitry 1702 includes a System on a Chip (SOC). In some embodiments, the processing circuitry 1702 includes one or more of Radio Frequency (RF) transceiver circuitry 1712 and baseband processing circuitry 1714. In some embodiments, the RF transceiver circuitry 1712 and the baseband processing circuitry 1714 may be on separate chips (or sets of chips), boards, or units, such as radio units and digital units. In alternative embodiments, part or all of the RF transceiver circuitry 1712 and the baseband processing circuitry 1714 may be on the same chip or set of chips, boards, or units. [0167] The memory 1704 may comprise any form of volatile or non-volatile computer- readable memory including, without limitation, persistent storage, solid state memory, remotely mounted memory, magnetic media, optical media, RAM, ROM, mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD), or a Digital Video Disk (DVD)), and/or any other volatile or non-volatile, non-transitory device- readable, and/or computer-executable memory devices that store information, data, and/or instructions that may be used by the processing circuitry 1702. The memory 1704 may store any suitable instructions, data, or information, including a computer program, software, an application including one or more of logic, rules, code, tables, and/or other instructions capable of being executed by the processing circuitry 1702 and utilized by the network node 1700. The memory 1704 may be used to store any calculations made by the processing circuitry 1702 and/or any data received via the communication interface 1706. In some embodiments, the processing circuitry 1702 and the memory 1704 are integrated. [0168] The communication interface 1706 is used in wired or wireless communication of signaling and/or data between a network node, access network, and/or UE. As illustrated, the communication interface 1706 comprises port(s)/terminal(s) 1716 to send and receive data, for example to and from a network over a wired connection. The communication interface 1706 also includes radio front-end circuitry 1718 that may be coupled to, or in certain embodiments a part of, the antenna 1710. The radio front-end circuitry 1718 comprises filters 1720 and amplifiers 1722. The radio front-end circuitry 1718 may be connected to the antenna 1710 and the processing circuitry 1702. The radio front-end circuitry 1718 may be configured to condition signals communicated between the antenna 1710 and the processing circuitry 1702. The radio front-end circuitry 1718 may receive digital data that is to be sent out to other network nodes or UEs via a wireless connection. The radio front-end circuitry 1718 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of the filters 1720 and/or the amplifiers 1722. The radio signal may then be transmitted via the antenna 1710. Similarly, when receiving data, the antenna 1710 may collect radio signals which are then converted into digital data by the radio front-end circuitry 1718. The digital data may be passed to the processing circuitry 1702. In other embodiments, the communication interface 1706 may comprise different components and/or different combinations of components. [0169] In certain alternative embodiments, the network node 1700 does not include separate radio front-end circuitry 1718; instead, the processing circuitry 1702 includes radio front-end circuitry and is connected to the antenna 1710. Similarly, in some embodiments, all or some of the RF transceiver circuitry 1712 is part of the communication interface 1706. In still other embodiments, the communication interface 1706 includes the one or more ports or terminals 1716, the radio front-end circuitry 1718, and the RF transceiver circuitry 1712 as part of a radio unit (not shown), and the communication interface 1706 communicates with the baseband processing circuitry 1714, which is part of a digital unit (not shown). [0170] The antenna 1710 may include one or more antennas, or antenna arrays, configured to send and/or receive wireless signals. The antenna 1710 may be coupled to the radio front-end circuitry 1718 and may be any type of antenna capable of transmitting and receiving data and/or signals wirelessly. In certain embodiments, the antenna 1710 is separate from the network node 1700 and connectable to the network node 1700 through an interface or port. [0171] The antenna 1710, the communication interface 1706, and/or the processing circuitry 1702 may be configured to perform any receiving operations and/or certain obtaining operations described herein as being performed by the network node 1700. Any information, data, and/or signals may be received from a UE, another network node, and/or any other network equipment. Similarly, the antenna 1710, the communication interface 1706, and/or the processing circuitry 1702 may be configured to perform any transmitting operations described herein as being performed by the network node 1700. Any information, data, and/or signals may be transmitted to a UE, another network node, and/or any other network equipment. [0172] The power source 1708 provides power to the various components of the network node 1700 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). The power source 1708 may further comprise, or be coupled to, power management circuitry to supply the components of the network node 1700 with power for performing the functionality described herein. For example, the network node 1700 may be connectable to an external power source (e.g., the power grid or an electricity outlet) via input circuitry or an interface such as an electrical cable, whereby the external power source supplies power to power circuitry of the power source 1708. As a further example, the power source 1708 may comprise a source of power in the form of a battery or battery pack which is connected to, or integrated in, power circuitry. The battery may provide backup power should the external power source fail. [0173] Embodiments of the network node 1700 may include additional components beyond those shown in Figure 17 for providing certain aspects of the network node’s functionality, including any of the functionality described herein and/or any functionality necessary to support the subject matter described herein. For example, the network node 1700 may include user interface equipment to allow input of information into the network node 1700 and to allow output of information from the network node 1700. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node 1700. [0174] Figure 18 is a block diagram of a host 1800, which may be an embodiment of the host 1516 of Figure 15, in accordance with various aspects described herein. As used herein, the host 1800 may be or comprise various combinations of hardware and/or software including a standalone server, a blade server, a cloud-implemented server, a distributed server, a virtual machine, container, or processing resources in a server farm. The host 1800 may provide one or more services to one or more UEs. [0175] The host 1800 includes processing circuitry 1802 that is operatively coupled via a bus 1804 to an input/output interface 1806, a network interface 1808, a power source 1810, and memory 1812. Other components may be included in other embodiments. Features of these components may be substantially similar to those described with respect to the devices of previous figures, such as Figures 16 and 17, such that the descriptions thereof are generally applicable to the corresponding components of the host 1800. [0176] The memory 1812 may include one or more computer programs including one or more host application programs 1814 and data 1816, which may include user data, e.g., data generated by a UE for the host 1800 or data generated by the host 1800 for a UE. Embodiments of the host 1800 may utilize only a subset or all of the components shown. The host application programs 1814 may be implemented in a container-based architecture and may provide support for video codecs (e.g., Versatile Video Coding (VVC), High Efficiency Video Coding (HEVC), Advanced Video Coding (AVC), Moving Picture Experts Group (MPEG), VP9) and audio codecs (e.g., Free Lossless Audio Codec (FLAC), Advanced Audio Coding (AAC), MPEG, G.711), including transcoding for multiple different classes, types, or implementations of UEs (e.g., handsets, desktop computers, wearable display systems, and heads-up display systems). The host application programs 1814 may also provide for user authentication and licensing checks and may periodically report health, routes, and content availability to a central node, such as a device in or on the edge of a core network. Accordingly, the host 1800 may select and/or indicate a different host for Over-The-Top (OTT) services for a UE. The host application programs 1814 may support various protocols, such as the HTTP Live Streaming (HLS) protocol, Real-Time Messaging Protocol (RTMP), Real-Time Streaming Protocol (RTSP), Dynamic Adaptive Streaming over HTTP (DASH or MPEG-DASH), etc. [0177] Figure 19 is a block diagram illustrating a virtualization environment 1900 in which functions implemented by some embodiments may be virtualized. In the present context, virtualizing means creating virtual versions of apparatuses or devices which may include virtualizing hardware platforms, storage devices, and networking resources. As used herein, virtualization can be applied to any device described herein, or components thereof, and relates to an implementation in which at least a portion of the functionality is implemented as one or more virtual components. Some or all of the functions described herein may be implemented as virtual components executed by one or more Virtual Machines (VMs) implemented in one or more virtual environments 1900 hosted by one or more of hardware nodes, such as a hardware computing device that operates as a network node, UE, core network node, or host. Further, in embodiments in which the virtual node does not require radio connectivity (e.g., a core network node or host), then the node may be entirely virtualized. In some embodiments, the virtualization environment 1900 includes components defined by the O-RAN Alliance, such as an O-Cloud environment orchestrated by a Service Management and Orchestration Framework via an O-2 interface. [0178] Applications 1902 (which may alternatively be called software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc.) are run in the virtualization environment 1900 to implement some of the features, functions, and/or benefits of some of the embodiments disclosed herein. [0179] Hardware 1904 includes processing circuitry, memory that stores software and/or instructions executable by hardware processing circuitry, and/or other hardware devices as described herein, such as a network interface, input/output interface, and so forth. Software may be executed by the processing circuitry to instantiate one or more virtualization layers 1906 (also referred to as hypervisors or VM Monitors (VMMs)), provide VMs 1908A and 1908B (one or more of which may be generally referred to as VMs 1908), and/or perform any of the functions, features, and/or benefits described in relation with some embodiments described herein. The virtualization layer 1906 may present a virtual operating platform that appears like networking hardware to the VMs 1908. [0180] The VMs 1908 comprise virtual processing, virtual memory, virtual networking, or interface and virtual storage, and may be run by a corresponding virtualization layer 1906. Different embodiments of the instance of a virtual appliance 1902 may be implemented on one or more of the VMs 1908, and the implementations may be made in different ways. Virtualization of the hardware is in some contexts referred to as Network Function Virtualization (NFV). NFV may be used to consolidate many network equipment types onto industry standard high volume server hardware, physical switches, and physical storage, which can be located in data centers and customer premise equipment. [0181] In the context of NFV, a VM 1908 may be a software implementation of a physical machine that runs programs as if they were executing on a physical, non-virtualized machine. Each of the VMs 1908, and that part of the hardware 1904 that executes that VM, be it hardware dedicated to that VM and/or hardware shared by that VM with others of the VMs 1908, forms separate virtual network elements. Still in the context of NFV, a virtual network function is responsible for handling specific network functions that run in one or more VMs 1908 on top of the hardware 1904 and corresponds to the application 1902. [0182] The hardware 1904 may be implemented in a standalone network node with generic or specific components. The hardware 1904 may implement some functions via virtualization. Alternatively, the hardware 1904 may be part of a larger cluster of hardware (e.g., such as in a data center or CPE) where many hardware nodes work together and are managed via management and orchestration 1910, which, among others, oversees lifecycle management of the applications 1902. In some embodiments, the hardware 1904 is coupled to one or more radio units that each include one or more transmitters and one or more receivers that may be coupled to one or more antennas. Radio units may communicate directly with other hardware nodes via one or more appropriate network interfaces and may be used in combination with the virtual components to provide a virtual node with radio capabilities, such as a RAN or a base station. In some embodiments, some signaling can be provided with the use of a control system 1912 which may alternatively be used for communication between hardware nodes and radio units. [0183] Figure 20 shows a communication diagram of a host 2002 communicating via a network node 2004 with a UE 2006 over a partially wireless connection in accordance with some embodiments. Example implementations, in accordance with various embodiments, of the UE (such as the UE 1512A of Figure 15 and/or the UE 1600 of Figure 16), the network node (such as the network node 1510A of Figure 15 and/or the network node 1700 of Figure 17), and the host (such as the host 1516 of Figure 15 and/or the host 1800 of Figure 18) discussed in the preceding paragraphs will now be described with reference to Figure 20. [0184] Like the host 1800, embodiments of the host 2002 include hardware, such as a communication interface, processing circuitry, and memory. The host 2002 also includes software, which is stored in or is accessible by the host 2002 and executable by the processing circuitry. The software includes a host application that may be operable to provide a service to a remote user, such as the UE 2006 connecting via an OTT connection 2050 extending between the UE 2006 and the host 2002. In providing the service to the remote user, a host application may provide user data which is transmitted using the OTT connection 2050. [0185] The network node 2004 includes hardware enabling it to communicate with the host 2002 and the UE 2006. The connection 2060 may be direct or pass through a core network (like the core network 1506 of Figure 15) and/or one or more other intermediate networks, such as one or more public, private, or hosted networks. For example, an intermediate network may be a backbone network or the Internet. [0186] The UE 2006 includes hardware and software, which is stored in or accessible by the UE 2006 and executable by the UE’s processing circuitry. The software includes a client application, such as a web browser or operator-specific “app” that may be operable to provide a service to a human or non-human user via the UE 2006 with the support of the host 2002. In the host 2002, an executing host application may communicate with the executing client application via the OTT connection 2050 terminating at the UE 2006 and the host 2002. In providing the service to the user, the UE's client application may receive request data from the host's host application and provide user data in response to the request data. The OTT connection 2050 may transfer both the request data and the user data. The UE's client application may interact with the user to generate the user data that it provides to the host application through the OTT connection 2050. [0187] The OTT connection 2050 may extend via the connection 2060 between the host 2002 and the network node 2004 and via a wireless connection 2070 between the network node 2004 and the UE 2006 to provide the connection between the host 2002 and the UE 2006. The connection 2060 and the wireless connection 2070, over which the OTT connection 2050 may be provided, have been drawn abstractly to illustrate the communication between the host 2002 and the UE 2006 via the network node 2004, without explicit reference to any intermediary devices and the precise routing of messages via these devices. [0188] As an example of transmitting data via the OTT connection 2050, in step 2008, the host 2002 provides user data, which may be performed by executing a host application. In some embodiments, the user data is associated with a particular human user interacting with the UE 2006. In other embodiments, the user data is associated with a UE 2006 that shares data with the host 2002 without explicit human interaction. In step 2010, the host 2002 initiates a transmission carrying the user data towards the UE 2006. The host 2002 may initiate the transmission responsive to a request transmitted by the UE 2006. The request may be caused by human interaction with the UE 2006 or by operation of the client application executing on the UE 2006. The transmission may pass via the network node 2004 in accordance with the teachings of the embodiments described throughout this disclosure. Accordingly, in step 2012, the network node 2004 transmits to the UE 2006 the user data that was carried in the transmission that the host 2002 initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In step 2014, the UE 2006 receives the user data carried in the transmission, which may be performed by a client application executed on the UE 2006 associated with the host application executed by the host 2002. [0189] In some examples, the UE 2006 executes a client application which provides user data to the host 2002. The user data may be provided in reaction or response to the data received from the host 2002. Accordingly, in step 2016, the UE 2006 may provide user data, which may be performed by executing the client application. In providing the user data, the client application may further consider user input received from the user via an input/output interface of the UE 2006. Regardless of the specific manner in which the user data was provided, the UE 2006 initiates, in step 2018, transmission of the user data towards the host 2002 via the network node 2004. In step 2020, in accordance with the teachings of the embodiments described throughout this disclosure, the network node 2004 receives user data from the UE 2006 and initiates transmission of the received user data towards the host 2002. In step 2022, the host 2002 receives the user data carried in the transmission initiated by the UE 2006. [0190] One or more of the various embodiments improve the performance of OTT services provided to the UE 2006 using the OTT connection 2050, in which the wireless connection 2070 forms the last segment. More precisely, the teachings of these embodiments may improve the e.g., data rate, latency, power consumption, etc. and thereby provide benefits such as e.g., reduced user waiting, relaxed restriction on file size, improved content resolution, better responsiveness, extended battery lifetime, etc. [0191] In an example scenario, factory status information may be collected and analyzed by the host 2002. As another example, the host 2002 may process audio and video data which may have been retrieved from a UE for use in creating maps. As another example, the host 2002 may collect and analyze real-time data to assist in controlling vehicle congestion (e.g., controlling traffic lights). As another example, the host 2002 may store surveillance video uploaded by a UE. As another example, the host 2002 may store or control access to media content such as video, audio, VR, or AR which it can broadcast, multicast, or unicast to UEs. As other examples, the host 2002 may be used for energy pricing, remote control of non-time critical electrical load to balance power generation needs, location services, presentation services (such as compiling diagrams etc. from data collected from remote devices), or any other function of collecting, retrieving, storing, analyzing, and/or transmitting data. [0192] In some examples, a measurement procedure may be provided for the purpose of monitoring data rate, latency, and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 2050 between the host 2002 and the UE 2006 in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring the OTT connection 2050 may be implemented in software and hardware of the host 2002 and/or the UE 2006. In some embodiments, sensors (not shown) may be deployed in or in association with other devices through which the OTT connection 2050 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or by supplying values of other physical quantities from which software may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 2050 may include message format, retransmission settings, preferred routing, etc.; the reconfiguring need not directly alter the operation of the network node 2004. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling that facilitates measurements of throughput, propagation times, latency, and the like by the host 2002. The measurements may be implemented in that software causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 2050 while monitoring propagation times, errors, etc. [0193] Although the computing devices described herein (e.g., UEs, network nodes, hosts) may include the illustrated combination of hardware components, other embodiments may comprise computing devices with different combinations of components. It is to be understood that these computing devices may comprise any suitable combination of hardware and/or software needed to perform the tasks, features, functions, and methods disclosed herein. Determining, calculating, obtaining, or similar operations described herein may be performed by processing circuitry, which may process information by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the network node, and/or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination. Moreover, while components are depicted as single boxes located within a larger box or nested within multiple boxes, in practice computing devices may comprise multiple different physical components that make up a single illustrated component, and functionality may be partitioned between separate components. For example, a communication interface may be configured to include any of the components described herein, and/or the functionality of the components may be partitioned between the processing circuitry and the communication interface. In another example, non-computationally intensive functions of any of such components may be implemented in software or firmware and computationally intensive functions may be implemented in hardware. [0194] In certain embodiments, some or all of the functionality described herein may be provided by processing circuitry executing instructions stored in memory, which in certain embodiments may be a computer program product in the form of a non-transitory computer- readable storage medium. In alternative embodiments, some or all of the functionality may be provided by the processing circuitry without executing instructions stored on a separate or discrete device-readable storage medium, such as in a hardwired manner. In any of those particular embodiments, whether executing instructions stored on a non-transitory computer-readable storage medium or not, the processing circuitry can be configured to perform the described functionality. The benefits provided by such functionality are not limited to the processing circuitry alone or to other components of the computing device, but are enjoyed by the computing device as a whole and/or by end users and a wireless network generally. [0195] Those skilled in the art will recognize improvements and modifications to the embodiments of the present disclosure. All such improvements and modifications are considered within the scope of the concepts disclosed herein. [0196] EMBODIMENTS [0197] Group A Embodiments [0198] Embodiment 1: A method performed by a user equipment, the method comprising one or more of: reporting UE capability for transmitting 3 Sounding Reference Signal, SRS, ports; [0199] being configured with a 4-port SRS resource; being configured to transmit only 3 out of said 4 SRS ports (e.g., one of the SRS ports is ‘blanked’/’muted’); receiving a control message (e.g., a DCI) to trigger SRS transmission; receiving a control message (e.g., a MAC CE) to activate SRS transmission; and transmitting 3 out of 4 SRS ports of 4-port SRS resource. [0200] Embodiment 2: A method performed by a user equipment, the method comprising one or more of: reporting UE capability for transmitting 3 SRS ports; being configured with a 3- port SRS resource; receiving a control message (e.g., a DCI) to trigger SRS transmission; receiving a control message (e.g., a MAC CE) to activate SRS transmission; and transmitting 3 SRS ports of the 3-port SRS resource. [0201] Embodiment 3: A method performed by a user equipment, the method comprising one or more of: reporting UE capability for transmitting 3 SRS ports; being configured with a 2- port SRS resource and a 1-port SRS resource in a same SRS resource set; receiving a control message (e.g., a DCI) to trigger SRS transmission; receiving a control message (e.g., a MAC CE) to activate SRS transmission; and transmitting 3 SRS ports of the 2-port SRS resource and the 1- port SRS resource. [0202] Embodiment 4: The method of any of the previous embodiments, wherein: new UE capability explicitly informs the network, NW, that UE is capable of transmitting 3 SRS ports. [0203] Embodiment 5: The method of any of the previous embodiments, wherein: UE reports a maximum number of SRS ports per SRS resource, ^₆-₇ ^{^-}. ^{[0204] Embodiment 6: The method of any of the previous embodiments, wherein: if ^-^-} ^{67 ≥} _{3, UE is capable of transmitting 3 SRS ports.} [0205] Embodiment 7: The method of any of the previous embodiments, wherein: a new field is added to SRS-Config IE such that NW can configure UE with blanking of 4-port SRS resource. [0206] Embodiment 8: The method of any of the previous embodiments, wherein: the new field is present if and only if the number of SRS ports in the SRS resource is 4. [0207] Embodiment 9: The method of any of the previous embodiments, wherein: if UE has indicated capability for 3-port SRS resource, it is understood (e.g., by both NW and UE) that UE will transmit only 3 out of the 4 ports if NW configures UE with 4-port SRS resource. [0208] Embodiment 10: The method of any of the previous embodiments, wherein: UE does not transmit the first SRS port in the SRS resource (e.g., the SRS port with lowest port index: 1000). [0209] Embodiment 11: The method of any of the previous embodiments, wherein: the UE does not transmit the last SRS port in the SRS resource (e.g., the SRS port with lowest port index: 1003). [0210] Embodiment 12: The method of any of the previous embodiments, wherein: which SRS port to ‘blank’/‘mute’ is configured by the NW. [0211] Embodiment 13: The method of any of the previous embodiments, wherein: 3 Tx UE must support 3 used CSs per comb offset if configured with muting of 4-port SRS resource. [0212] Embodiment 14: The method of any of the previous embodiments, wherein: UE reports capability of supporting 3 CSs per comb offset if configured with muting of 4-port SRS resource. [0213] Embodiment 15: The method of any of the previous embodiments, wherein: UE is not expected to be configured with 4 (3 after blanking) CSs per comb offset if blanking of 4-port SRS resource is configured. [0214] Embodiment 16: The method of any of the previous embodiments, wherein: UE reports capability of supporting uneven number of CSs per comb offset if configured with muting of 4-port SRS resource. [0215] Embodiment 17: The method of any of the previous embodiments, wherein: UE is not expected to be configured with uneven number of CSs per comb offset if blanking of 4-port SRS resource is configured. [0216] Embodiment 18: The method of any of the previous embodiments, wherein: comb 8 (e.g., for which the 4 SRS ports must be spread over multiple comb offsets, which is an optional configuration for comb 2 and 4) cannot be configured at the same time as muting of a 4-port SRS resource (e.g., UE is not expected be configured with muting and comb 8 at the same time). [0217] Embodiment 19: The method of any of the previous embodiments, wherein: for a muted 4-port SRS resource, the UE splits transmit power G_-^-,H,I,J linearly over 3 SRS ports, such that the total SRS power is G_-^-,H,I,J. [0218] Embodiment 20: The method of any of the previous embodiments, wherein: for a muted 4-port SRS resource, the UE splits transmit power G_-^-,H,I,J linearly over 4 SRS ports, such that the total SRS power is 0.75 ∙ G_-^-,H,I,J. [0219] Embodiment 21: The method of any of the previous embodiments, wherein: for a muted 4-port SRS resource configured to map SRS ports to two different comb offsets, UE splits half of the transmit over the 2 SRS ports mapped to a first comb offset and half of the transmit ^{power over the 1 SRS port mapped to a second comb offset, such that the total SRS power is} _G-^-,H,I,J. [0220] Embodiment 22: The method of any of the previous embodiments, wherein: a new field for configuring the number of SRS ports is added in SRS-Config IE such that NW can configure 3-port SRS resource. [0221] Embodiment 23: The method of any of the previous embodiments, wherein: when this new field is configured, UE shall ignore the value of the field nrofSRS-ports. [0222] Embodiment 24: The method of any of the previous embodiments, wherein: a 3-port SRS resource maps all SRS ports onto a single comb offset (e.g., 3 ports per comb offset) and where the mapping is such that SRS ports are equidistantly spaced. [0223] Embodiment 25: The method of any of the previous embodiments, wherein: a 3-port SRS resource cannot be configured with comb 2 (UE is not expected be configured with 3 SRS ports and comb 2 at the same time). [0224] Embodiment 26: The method of any of the previous embodiments, wherein: 3 SRS ports is mapped to a single comb offset in such a way that CSs are not equidistantly separated (e.g., CS 0 + M, 3 + M, 6 + M for comb 2). [0225] Embodiment 27: The method of any of the previous embodiments, wherein: SRS ports in a 3-port SRS resource are mapped to CSs and comb offsets in such a way that 2 SRS ports is mapped to a first comb offset and 1 SRS port is mapped to a second offset. [0226] Embodiment 28: The method of any of the previous embodiments, wherein: for comb 4 and/or 8, SRS ports in a 3-port SRS resource are mapped to three different comb offsets. [0227] Embodiment 29: The method of any of the previous embodiments, wherein: the SRS power in the OFDM symbol containing the 1-port SRS resource half of the SRS power in the OFDM symbol containing the 2-port SRS resource (e.g., such that the power per SRS ports is the same over the 3 SRS ports). [0228] Embodiment 30: The method of any of the previous embodiments, wherein: UE is required to transmit the two SRS resources such that coherence is maintained over, at least, a subset of the three SRS ports. [0229] Embodiment 31: The method of any of the previous embodiments, wherein: if SRS ports are in an SRS resource set with usage set to codebook, and if UE has reported capability for partially-coherent precoding, UE is expected to maintain coherence when transmitting PUSCH over the two SRS ports in the 2-port SRS resource. [0230] Embodiment 32: The method of any of the previous embodiments, wherein: if SRS ports are in an SRS resource set with usage set to codebook, and if UE has reported capability for fully-coherent precoding, UE is expected to maintain coherence when transmitting PUSCH over the three SRS ports in the 2-port SRS resource and the SRS port in the 1-port SRS resource. [0231] Embodiment 33: The method of any of the previous embodiments, wherein: instead of combining two SRS resources, three 1-port SRS resources are combined. [0232] Embodiment 34: The method of any of the previous embodiments, further comprising: providing user data; and forwarding the user data to a host via the transmission to the network node. [0233] Group B Embodiments [0234] Embodiment 35: A method performed by a network node, the method comprising one or more of: receiving a report of UE capability for transmitting 3 SRS ports; configuring the UE with a 4-port SRS resource; configuring the UE to transmit only 3 out of said 4 SRS ports (e.g., one of the SRS ports is ‘blanked’/’muted’); transmitting a control message (e.g., a DCI) to trigger SRS transmission; transmitting a control message (e.g., a MAC CE) to activate SRS transmission; and receiving 3 out of 4 SRS ports of 4-port SRS resource. [0235] Embodiment 36: A method performed by a network node, the method comprising one or more of: receiving a report of UE capability for transmitting 3 SRS ports; configuring the UE with a 3-port SRS resource; transmitting a control message (e.g., a DCI) to trigger SRS transmission; transmitting a control message (e.g., a MAC CE) to activate SRS transmission; and receiving 3 SRS ports of the 3-port SRS resource. [0236] Embodiment 37: A method performed by a network node, the method comprising one or more of: receiving a report of UE capability for transmitting 3 SRS ports; configuring the UE with a 2-port SRS resource and a 1-port SRS resource in a same SRS resource set; transmitting a control message (e.g., a DCI) to trigger SRS transmission; transmitting a control message (e.g., a MAC CE) to activate SRS transmission; and receiving 3 SRS ports of the 2-port SRS resource and the 1-port SRS resource. [0237] Embodiment 38: The method of any of the previous embodiments further comprising the features of any of the Group A embodiments. [0238] Embodiment 39: The method of any of the previous embodiments, further comprising: obtaining user data; and forwarding the user data to a host or a user equipment. [0239] Group C Embodiments [0240] Embodiment 40: A user equipment, comprising: processing circuitry configured to perform any of the steps of any of the Group A embodiments; and power supply circuitry configured to supply power to the processing circuitry. [0241] Embodiment 41: A network node, the network node comprising: processing circuitry configured to perform any of the steps of any of the Group B embodiments; and power supply circuitry configured to supply power to the processing circuitry. [0242] Embodiment 42: A user equipment (UE), the UE comprising: an antenna configured to send and receive wireless signals; radio front-end circuitry connected to the antenna and to processing circuitry, and configured to condition signals communicated between the antenna and the processing circuitry; the processing circuitry being configured to perform any of the steps of any of the Group A embodiments; an input interface connected to the processing circuitry and configured to allow input of information into the UE to be processed by the processing circuitry; an output interface connected to the processing circuitry and configured to output information from the UE that has been processed by the processing circuitry; and a battery connected to the processing circuitry and configured to supply power to the UE. [0243] Embodiment 43: A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a network node in a cellular network for transmission to a user equipment (UE), the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments to transmit the user data from the host to the UE. [0244] Embodiment 44: The host of the previous embodiment, wherein: the processing circuitry of the host is configured to execute a host application that provides the user data; and the UE comprises processing circuitry configured to execute a client application associated with the host application to receive the transmission of user data from the host. [0245] Embodiment 45: A method implemented in a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: providing user data for the UE; and initiating a transmission carrying the user data to the UE via a cellular network comprising the network node, wherein the network node performs any of the operations of any of the Group B embodiments to transmit the user data from the host to the UE. [0246] Embodiment 46: The method of the previous embodiment, further comprising, at the network node, transmitting the user data provided by the host for the UE. [0247] Embodiment 47: The method of any of the previous 2 embodiments, wherein the user data is provided at the host by executing a host application that interacts with a client application executing on the UE, the client application being associated with the host application. [0248] Embodiment 48: A communication system configured to provide an over-the-top (OTT) service, the communication system comprising: a host comprising: processing circuitry configured to provide user data for a user equipment (UE), the user data being associated with the over-the-top service; and a network interface configured to initiate transmission of the user data toward a cellular network node for transmission to the UE, the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments to transmit the user data from the host to the UE. [0249] Embodiment 49: The communication system of the previous embodiment, further comprising: the network node; and/or the UE. [0250] Embodiment 50: A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to initiate receipt of user data; and a network interface configured to receive the user data from a network node in a cellular network, the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments to receive the user data from a user equipment (UE) for the host. [0251] Embodiment 51: The host of the previous 2 embodiments, wherein: the processing circuitry of the host is configured to execute a host application that receives the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application. [0252] Embodiment 52: The host of the any of the previous 2 embodiments, wherein the initiating receipt of the user data comprises requesting the user data. [0253] Embodiment 53: A method implemented by a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: at the host, initiating receipt of user data from the UE, the user data originating from a transmission which the network node has received from the UE, wherein the network node performs any of the steps of any of the Group B embodiments to receive the user data from the UE for the host. [0254] Embodiment 54: The method of the previous embodiment, further comprising at the network node, transmitting the received user data to the host. [0255] Embodiment 55: A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a cellular network for transmission to a user equipment (UE), wherein the UE comprises a communication interface and processing circuitry, the communication interface and processing circuitry of the UE being configured to perform any of the operations of any of the Group A embodiments to receive the user data from the host. [0256] Embodiment 56: The host of the previous embodiment, wherein the cellular network further includes a network node configured to communicate with the UE to transmit the user data to the UE from the host. [0257] Embodiment 57: The host of the previous 2 embodiments, wherein: the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application. [0258] Embodiment 58: A method implemented by a host operating in a communication system that further includes a network node and a user equipment (UE), the method comprising: providing user data for the UE; and initiating a transmission carrying the user data to the UE via a cellular network comprising the network node, wherein the UE performs any of the operations of any of the Group A embodiments to receive the user data from the host. [0259] Embodiment 59: The method of the previous embodiment, further comprising: at the host, executing a host application associated with a client application executing on the UE to receive the user data from the host application. [0260] Embodiment 60: The method of the previous embodiment, further comprising: at the host, transmitting input data to the client application executing on the UE, the input data being provided by executing the host application, wherein the user data is provided by the client application in response to the input data from the host application. [0261] Embodiment 61: A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a cellular network for transmission to a user equipment (UE), wherein the UE comprises a communication interface and processing circuitry, the communication interface and processing circuitry of the UE being configured to perform any of the steps of any of the Group A embodiments to transmit the user data to the host. [0262] Embodiment 62: The host of the previous embodiment, wherein the cellular network further includes a network node configured to communicate with the UE to transmit the user data from the UE to the host. [0263] Embodiment 63: The host of the previous 2 embodiments, wherein: the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application. [0264] Embodiment 64: A method implemented by a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: at the host, receiving user data transmitted to the host via the network node by the UE, wherein the UE performs any of the steps of any of the Group A embodiments to transmit the user data to the host. [0265] Embodiment 65: The method of the previous embodiment, further comprising: at the host, executing a host application associated with a client application executing on the UE to receive the user data from the UE. [0266] Embodiment 66: The method of the previous 2 embodiments, further comprising: at the host, transmitting input data to the client application executing on the UE, the input data being provided by executing the host application, wherein the user data is provided by the client application in response to the input data from the host application.

ABBREVIATIONS At least some of the following abbreviations may be used in this disclosure. If there is an inconsistency between abbreviations, preference should be given to how it is used above. If listed multiple times below, the first listing should be preferred over any subsequent listing(s). 1x RTT CDMA2000 1x Radio Transmission Technology 3GPP Third Generation Partnership Project ap-SRS Aperiodic SRS ASN Abstract Syntax Notation BPSK Binary Phase Shift Keying BWP Bandwidth Part CA Carrier Aggregation CB Codebook CDM Code Division Multiplexing CE Control Element CP-OFDM Cyclic Prefix OFDM CPE Consumer Peripheral Equipment CRB Carrier RB CG Configured Grant CO Comb Offset CS Cyclic Shift CS-RNTI Configured Scheduling RNTI CSI Channel State Information DCI Downlink Control Information DFT Discrete Fourier Transform DFT-S-OFDM DFT Spread OFDM DG Dynamic Grant DL Downlink DMRS Demodulation RS FD-OCC Frequency Domain OCC FDD Frequency-Division Multiplexing FR1 Frequency Range 1 FR2 Frequency Range 2 FWA Fixed Wireless Access IDFT Inverse DFT gNB gNodeB IE Information Element LSB Least Significant Bit LTE Long Term Evolution MAC Medium Access Control MCS Modulation and Coding Scheme MIB Master Information Block MIMO Multiple-Input Multiple-Output MSB Most Significant Bit NCB Non-Codebook NDI New Data Indicator NR New Radio NW Network OCC Orthogonal Cover Code OFDM Orthogonal Frequency Division Multiplexing p-SRS Periodic SRS PA Power Amplifier PAPR Peak-to-Average Power Ratio PC Power Control PCell Primary Cell PDCCH Physical Downlink Control Channel PDSCH Physical Downlink Shared Channel PRB Physical RB PSD Power Spectral Density PTRS Phase Tracking Reference Signal PUCCH Physical Uplink Control Channel PUSCH Physical Uplink Shared Channel QPSK Quadrature Phase-Shift Keying RB Resource Block RBG Resource Block Group RE Resource Element RF Radio Frequency RS Reference Signal RSRP RS Received Power RIV Resource Indication Value RNTI Radio Network Temporary Identifier RRC Radio Resource Control RV Redundancy Version Rx Receive SCS Subcarrier Spacing SCell Secondary Cell SIB1 System Information Block 1 SLIV Start and Length Indicator Value sp-SRS Semi-Persistent SRS SNR Signal-to-Noise Ratio SRI SRS Resource Indicator SRS Sounding Reference Signal SRSI SRS Resource Set Indicator SSB Synchronization Signal Block SUL Supplementary Uplink TB Transport Block TD-OCC Time Domain OCC TDD Time-Division Duplexing Tx Transmit UE User Equipment UL Uplink VRB Virtual RB 3GPP 3rd Generation Partnership Project 5G 5th Generation 6G 6th Generation ABS Almost Blank Subframe ARQ Automatic Repeat Request AWGN Additive White Gaussian Noise BCCH Broadcast Control Channel BCH Broadcast Channel CA Carrier Aggregation CC Carrier Component CCCH SDU Common Control Channel SDU CDMA Code Division Multiplexing Access CE Control Element CGI Cell Global Identifier CIR Channel Impulse Response CP Cyclic Prefix CPICH Common Pilot Channel CPICH Ec/No CPICH Received energy per chip divided by the power density in the band CQI Channel Quality information C-RNTI Cell RNTI CS Cyclic Shift CSI Channel State Information DCCH Dedicated Control Channel DL Downlink DM Demodulation DMRS Demodulation Reference Signal DRX Discontinuous Reception DTX Discontinuous Transmission DTCH Dedicated Traffic Channel DUT Device Under Test E-CID Enhanced Cell-ID (positioning method) eMBMS evolved Multimedia Broadcast Multicast Services E-SMLC Evolved-Serving Mobile Location Centre ECGI Evolved CGI eNB E-UTRAN NodeB ePDCCH Enhanced Physical Downlink Control Channel E-SMLC Evolved Serving Mobile Location Center E-UTRA Evolved UTRA E-UTRAN Evolved UTRAN FDD Frequency Division Duplex FFS For Further Study gNB Base station in NR GNSS Global Navigation Satellite System HARQ Hybrid Automatic Repeat Request HO Handover HSPA High Speed Packet Access HRPD High Rate Packet Data LOS Line of Sight LPP LTE Positioning Protocol LTE Long-Term Evolution MAC Medium Access Control MAC Message Authentication Code MBSFN Multimedia Broadcast multicast service Single Frequency Network MBSFN ABS MBSFN Almost Blank Subframe MDT Minimization of Drive Tests MIB Master Information Block MME Mobility Management Entity MSC Mobile Switching Center NPDCCH Narrowband Physical Downlink Control Channel NR New Radio OCNG OFDMA Channel Noise Generator OFDM Orthogonal Frequency Division Multiplexing OFDMA Orthogonal Frequency Division Multiple Access OSS Operations Support System OTDOA Observed Time Difference of Arrival O&M Operation and Maintenance PBCH Physical Broadcast Channel P-CCPCH Primary Common Control Physical Channel PCell Primary Cell PCFICH Physical Control Format Indicator Channel PDCCH Physical Downlink Control Channel PDCP Packet Data Convergence Protocol PDP Profile Delay Profile PDSCH Physical Downlink Shared Channel PGW Packet Gateway PHICH Physical Hybrid-ARQ Indicator Channel PLMN Public Land Mobile Network PMI Precoder Matrix Indicator PRACH Physical Random Access Channel PRS Positioning Reference Signal PSS Primary Synchronization Signal PUCCH Physical Uplink Control Channel PUSCH Physical Uplink Shared Channel RACH Random Access Channel QAM Quadrature Amplitude Modulation RAN Radio Access Network RAT Radio Access Technology RLC Radio Link Control RLM Radio Link Management RNC Radio Network Controller RNTI Radio Network Temporary Identifier RRC Radio Resource Control RRM Radio Resource Management RS Reference Signal RSCP Received Signal Code Power RSRP Reference Symbol Received Power OR Reference Signal Received Power RSRQ Reference Signal Received Quality OR Reference Symbol Received Quality RSSI Received Signal Strength Indicator RSTD Reference Signal Time Difference SCH Synchronization Channel SCell Secondary Cell SDAP Service Data Adaptation Protocol SDU Service Data Unit SFN System Frame Number SGW Serving Gateway SI System Information SIB System Information Block SNR Signal to Noise Ratio SON Self Optimized Network SRS Sounding Reference Signal SS Synchronization Signal SSS Secondary Synchronization Signal TDD Time Division Duplex TDOA Time Difference of Arrival TOA Time of Arrival TSS Tertiary Synchronization Signal TTI Transmission Time Interval UE User Equipment UL Uplink USIM Universal Subscriber Identity Module UTDOA Uplink Time Difference of Arrival WCDMA Wide CDMA WLAN Wide Local Area Network .

Claims

CLAIMS 1. A method performed by a User Equipment, UE, the method comprising: receiving a configuration with a four-port Sounding Reference Signal, SRS, resource; receiving a control message to trigger/activate an SRS transmission; and transmitting three out of four SRS ports of the four-port SRS resource. 2. The method of claim 1 further comprising: reporting UE capability for transmitting three SRS ports. 3. The method of any of claims 1 to 2 further comprising: being explicitly configured to transmit only three out of the four SRS ports. 4. The method of claim 3 wherein being explicitly configured comprises: receiving an indication that one of the SRS ports is muted. 5. The method of any of claims 1 to 4 wherein receiving the control message comprises: receiving a Downlink Control Information, DCI, to trigger SRS transmission. 6. The method of any of claims 1 to 4 wherein receiving the control message comprises: receiving a Medium Access Control, MAC, Control Element, CE, to activate SRS transmission. 7. The method of any of claims 2 to 6 wherein the UE capability comprises: a new UE capability that explicitly informs the network that UE is capable of transmitting three SRS ports. 8. The method of any of claims 2 to 7 wherein reporting the UE capability comprises: reporting a maximum number of SRS ports per SRS resource, ^₆-₇ ^{^-}. 9. The method of claim 8, wherein: if ^₆-₇ ^{^-} ≥ 3, the UE is capable of transmitting three SRS ports. 10. The method of any of claims 3 to 9, wherein being explicitly configured to transmit only three out of the four SRS ports comprises: a new field being added to an SRS-Config IE such that the UE can be configured with muting of the four-port SRS resource. 11. The method of claim 10, wherein: the new field is present if and only if the number of SRS ports in the SRS resource is four. 12. The method of any of claims 1 to 11, wherein: the UE does not transmit SRS port 1003. 13. The method of any of claims 1 to 11, wherein: the UE does not transmit the last SRS port in the SRS resource. 14. The method of any of claims 1 to 13, wherein: which SRS port to mute is configured. 15. The method of any of claims 1 to 14, further comprising: supporting three used Cyclic Shifts, CSs, per comb offset if configured with muting of the four-port SRS resource. 16. The method of any of claims 1 to 15, further comprising: reporting capability of supporting three CSs per comb offset if configured with muting of the four-port SRS resource. 17. The method of any of claims 1 to 16, further comprising: reporting capability of supporting uneven number of CSs per comb offset if configured with muting of the four-port SRS resource. 18. The method of any of claims 1 to 17, further comprising: splitting transmit power G_-^-,H,I,J linearly over the three SRS ports, such that the total SRS power is G_-^-,H,I,J. 19. The method of any of claims 1 to 18, wherein: a 3-port SRS resource maps all SRS ports onto a single comb offset and where the mapping is such that SRS ports are equidistantly spaced. 20. The method of any of claims 1 to 18, wherein: SRS ports in a 3-port SRS resource are mapped to CSs and comb offsets in such a way that two SRS ports is mapped to a first comb offset and one SRS port is mapped to a second offset. 21. A method performed by a network node, the method comprising: transmitting, to a User Equipment, UE, a configuration with a four-port Sounding Reference Signal, SRS, resource; transmitting, to the UE, a control message to trigger/activate an SRS transmission; and receiving, from the UE, three out of four SRS ports of the four-port SRS resource. 22. The method of claim 21 further comprising: receiving UE capability for transmitting three SRS ports. 23. The method of any of claims 21 to 22 further comprising: explicitly configuring the UE to transmit only three out of the four SRS ports; 24. The method of claim 23 wherein explicitly configuring comprises: transmitting an indication that one of the SRS ports is muted. 25. The method any of claims 21 to 24 wherein transmitting the control message comprises: transmitting a Downlink Control Information, DCI, to trigger SRS transmission. 26. The method of any of claims 21 to 24 wherein transmitting the control message comprises: transmitting a Medium Access Control, MAC, Control Element, CE, to activate SRS transmission. 27. The method of any of claims 22 to 26 wherein the UE capability comprises: a new UE capability that explicitly informs the network that UE is capable of transmitting three SRS ports. 28. The method of any of claims 22 to 27 wherein receiving the UE capability comprises: receiving a maximum number of SRS ports per SRS resource, ^₆-₇ ^{^-}. 29. The method of claim 28, wherein: if ^₆-₇ ^{^-} ≥ 3, the UE is capable of transmitting three SRS ports. 30. The method of any of claims 23 to 29, wherein explicitly configuring the UE to transmit only three out of the four SRS ports comprises: a new field is added to SRS-Config IE such that the UE can be configured with muting of the four-port SRS resource. 31. The method of claim 30, wherein: the new field is present if and only if the number of SRS ports in the SRS resource is four.

32. The method of any of claims 21 to 31, wherein: the UE does not transmit SRS port 1003. 33. The method of any of claims 21 to 31, wherein: the UE does not transmit the last SRS port in the SRS resource. 34. The method of any of claims 21 to 33, wherein: which SRS port to mute is configured. 35. The method of any of claims 21 to 34, further comprising: the UE supporting three used Cyclic Shifts, CSs, per comb offset if configured with muting of four-port SRS resource. 36. The method of any of claims 21 to 35, further comprising: receiving a capability report of supporting three CSs per comb offset if configured with muting of four-port SRS resource. 37. The method of any of claims 21 to 36, further comprising: receiving a capability report of supporting uneven number of CSs per comb offset if configured with muting of four-port SRS resource. ^{38. The method of any of claims 21 to 37, further comprising: receiving split transmit power} _{G-^-,H,I,J linearly over the three SRS ports, such that the total SRS power is G-^-,H,I,J.} 39. The method of any of claims 21 to 38, wherein: a 3-port SRS resource maps all SRS ports onto a single comb offset and where the mapping is such that SRS ports are equidistantly spaced. 40. The method of any of claims 21 to 38, wherein: SRS ports in a 3-port SRS resource are mapped to CSs and comb offsets in such a way that two SRS ports is mapped to a first comb offset and one SRS port is mapped to a second offset. 41. A User Equipment, UE, (1600) comprising processing circuitry (1602) and memory (1610), the memory (1610) comprising instructions to cause the UE (1600) to: receive a configuration with a four-port Sounding Reference Signal, SRS, resource; receive a control message to trigger/activate an SRS transmission; and transmit three out of four SRS ports of the four-port SRS resource.

42. The UE (1600) of claim 41 further operable to implement the features of any of claims 2- 20. 43. A computer-readable medium comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to any one of claims 1 to 20. 44. A network node (1700) comprising processing circuitry (1702) and memory (1704), the memory (1704) comprising instructions to cause the network node (1700) to: transmit, to a User Equipment, UE, a configuration with a four-port Sounding Reference Signal, SRS, resource; transmit, to the UE, a control message to trigger/activate an SRS transmission; and receive, from the UE, three out of four SRS ports of the four-port SRS resource. 45. The network node (1700) of claim 44 further operable to implement the features of any of claims 22-40. 46. A computer-readable medium comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to any one of claims 21 to 40. 47. A method performed by a User Equipment, UE, the method comprising: receiving a configuration with a 3-port Sounding Reference Signal, SRS, resource; receiving a control message to trigger/activate an SRS transmission; and transmitting three SRS ports of the 3-port SRS resource. 48. The method of claim 47 further comprising: reporting UE capability for transmitting three SRS ports. 49. The method of any of claims 47 to 48 wherein receiving the control message comprises: receiving a Downlink Control Information, DCI, to trigger SRS transmission. 50. The method of any of claims 47 to 48 wherein receiving the control message comprises: receiving a Medium Access Control, MAC, Control Element, CE, to activate SRS transmission. 47. A method performed by a network node, the method comprising: transmitting, to a User Equipment, UE, a configuration with a 3-port Sounding Reference Signal, SRS, resource; transmitting, to the UE, a control message to trigger/activate an SRS transmission; and receiving, from the UE, three SRS ports of the 3-port SRS resource. 48. The method of claim 47 further comprising: receiving UE capability for transmitting three SRS ports. 49. The method of any of claims 47 to 48 wherein transmitting the control message comprises: transmitting a Downlink Control Information, DCI, to trigger SRS transmission. 50. The method of any of claims 47 to 48 wherein transmitting the control message comprises: transmitting a Medium Access Control, MAC, Control Element, CE, to activate SRS transmission.