WO2024207161A1

WO2024207161A1 - Sounding reference signal transmission

Info

Publication number: WO2024207161A1
Application number: PCT/CN2023/086044
Authority: WO
Inventors: Jie Gao; Navin Hathiramani; Nitin MANGALVEDHE; Rapeepat Ratasuk
Original assignee: Nokia Shanghai Bell Co Ltd; Nokia Solutions and Networks Oy; Nokia Technologies Oy
Current assignee: Nokia Shanghai Bell Co Ltd; Nokia Solutions and Networks Oy; Nokia Technologies Oy
Priority date: 2023-04-03
Filing date: 2023-04-03
Publication date: 2024-10-10
Anticipated expiration: 2025-10-03
Also published as: CN120898394A

Abstract

Embodiments of the present disclosure relate to devices, methods, apparatuses and computer readable storage media of a transmitting a sounding reference signal (SRS). The method comprises obtaining, by a terminal device, a configuration for transmitting a SRS associated with a scheduled Message3 or Message A, wherein the configuration corresponds to attribute information associated with the terminal device; and transmitting, from the terminal device to a network device, the SRS using the configuration during a random access procedure.

Description

SOUNDING REFERENCE SIGNAL TRANSMISSION

FIELD

Embodiments of the present disclosure generally relate to the field of telecommunication and in particular to devices, methods, apparatuses and computer readable storage media of transmitting a sounding reference signal (SRS) .

BACKGROUND

In 5th Generation Mobile Communication Technology (5G) new radio (NR) , two contention based random access (CBRA) procedures are supported, namely 4-step random access procedure (i.e., RACH) and 2-step random access procedure.

SUMMARY

In a first aspect, there is provided an apparatus. The apparatus comprises at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to obtain a configuration for transmitting a sounding reference signal (SRS) associated with a scheduled Message3 or Message A, wherein the configuration corresponds to attribute information associated with the apparatus; and transmit, to a network device, the SRS using the configuration during a random access procedure.

In a second aspect, there is provided an apparatus. The apparatus comprises at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to receive an SRS transmitted from a terminal device during a random access procedure, by using a configuration for transmitting the SRS, wherein the configuration corresponds to attribute information associated with the terminal device.

In a third aspect, there is provide a method. The method comprises obtaining, by a terminal device, a configuration for transmitting an SRS associated with a scheduled Message3 or Message A, wherein the configuration corresponds to attribute information associated with the terminal device; and transmitting, by the terminal device to a network device, the SRS using the configuration during a random access procedure.

In a fourth aspect, there is provide a method. The method comprises receiving, by a network device, an SRS transmitted from a terminal device during a random access procedure, by using a configuration for transmitting the SRS, wherein the configuration corresponds to attribute information associated with the terminal device.

In a fifth aspect, there is provided an apparatus comprising means for obtaining a configuration for transmitting an SRS associated with a scheduled Message3 or Message A, wherein the configuration corresponds to attribute information associated with the apparatus; and means for transmitting, to a network device, the SRS using the configuration during a random access procedure.

In a sixth aspect, there is provided an apparatus comprising means for receiving an SRS transmitted from a terminal device during a random access procedure, by using a configuration for transmitting the SRS, wherein the configuration corresponds to attribute information associated with the terminal device.

In a seven aspect, there is provided a non-transitory computer readable medium comprising program instructions that, when executed by an apparatus, cause the apparatus at least to obtain a configuration for transmitting a sounding reference signal (SRS) associated with a scheduled Message3 or Message A, wherein the configuration corresponds to attribute information associated with the apparatus; and transmit, to a network device, the SRS using the configuration during a random access procedure.

In an eighth aspect, there is provided a non-transitory computer readable medium comprising program instructions that, when executed by an apparatus, cause the apparatus at least to receive an SRS transmitted from a terminal device during a random access procedure, by using a configuration for transmitting the SRS, wherein the configuration corresponds to attribute information associated with the terminal device.

In a ninth aspect, there is provided a computer program comprising instructions which, when executed by an apparatus, cause the apparatus at least to obtain a configuration for transmitting a sounding reference signal (SRS) associated with a scheduled Message3 or Message A, wherein the configuration corresponds to attribute information associated with the apparatus; and transmit, to a network device, the SRS using the configuration during a random access procedure.

In a tenth aspect, there is provided a computer program comprising instructions which, when executed by an apparatus, cause the apparatus at least to receive an SRS transmitted from a terminal device during a random access procedure, by using a configuration for transmitting the SRS, wherein the configuration corresponds to attribute information associated with the terminal device.

Other features and advantages of the embodiments of the present disclosure will also be apparent from the following description of specific embodiments when read in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of embodiments of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the disclosure are presented in the sense of examples and their advantages are explained in greater detail below, with reference to the accompanying drawings.

FIG. 1 illustrates an example environment in which example embodiments of the present disclosure may be implemented;

FIG. 2 shows a signaling chart illustrating an example of process according to some example embodiments of the present disclosure;

FIGS. 3A and 3B show examples of a new MSG3/MSGA structure according to some example embodiments of the present disclosure;

FIG. 4 shows a signaling chart illustrating an example of process according to some example embodiments of the present disclosure;

FIG. 5 shows an example of a new MSG3/MSGA structure according to some example embodiments of the present disclosure;

FIG. 6 shows a flowchart of an example method of transmitting an SRS according to some example embodiments of the present disclosure;

FIG. 7 shows a flowchart of an example method of transmitting an SRS according to some example embodiments of the present disclosure;

FIG. 8 shows a simplified block diagram of a device that is suitable for implementing example embodiments of the present disclosure; and

FIG. 9 shows a block diagram of an example computer readable medium in accordance with some embodiments of the present disclosure.

Throughout the drawings, the same or similar reference numerals may represent the same or similar element.

DETAILED DESCRIPTION

Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. Embodiments described herein may be implemented in various manners other than the ones described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein may have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

References in the present disclosure to “one embodiment, ” “an embodiment, ” “an example embodiment, ” and the like indicate that the embodiment described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

It shall be understood that although the terms “first, ” “second” and the like may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the listed terms.

As used herein, “at least one of the following: <a list of two or more elements>” and “at least one of <a list of two or more elements>” and similar wording, where the list of two or more elements are joined by “and” or “or” , mean at least any one of the elements, or at least any two or more of the elements, or at least all the elements.

As used herein, unless stated explicitly, performing a step “in response to A” does not indicate that the step is performed immediately after “A” occurs and one or more intervening steps may be included.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a” , “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” , “comprising” , “has” , “having” , “includes” and/or “including” , when used herein, specify the presence of stated features, elements, and/or components etc., but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof.

As used in this application, the term “circuitry” may refer to one or more or all of the following:

(a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and

(b) combinations of hardware circuits and software, such as (as applicable) :

(i) a combination of analog and/or digital hardware circuit (s) with software/firmware and

(ii) any portions of hardware processor (s) with software (including digital signal processor (s) ) , software, and memory (ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and

(c) hardware circuit (s) and or processor (s) , such as a microprocessor (s) or a portion of a microprocessor (s) , that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.

This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

As used herein, the term “communication network” refers to a network following any suitable communication standards, such as New Radio (NR) , Long Term Evolution (LTE) , LTE-Advanced (LTE-A) , Wideband Code Division Multiple Access (WCDMA) , High-Speed Packet Access (HSPA) , Narrow Band Internet of Things (NB-IoT) , an Enhanced Machine type communication (eMTC) and so on. Furthermore, the communications between a terminal device and a network device in the communication network may be performed according to any suitable generation communication protocols, including, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.75G, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) communication protocols, and/or any other protocols either currently known or to be developed in the future. Embodiments of the present disclosure may be applied in various communication systems. Given the rapid development in communications, there will of course also be future type communication technologies and systems with which the present disclosure may be embodied. It should not be seen as limiting the scope of the present disclosure to only the aforementioned system.

As used herein, the terms “network device” , “radio network device” and/or “radio access network device” refers to a node in a communication network via which a terminal device accesses the network and receives services therefrom. The network device may refer to a base station (BS) or an access point (AP) , for example, a node B (NodeB or NB) , an evolved NodeB (eNodeB or eNB) , an NR NB (also referred to as a gNB) , a Remote Radio Unit (RRU) , a radio header (RH) , a remote radio head (RRH) , a relay, an Integrated Access and Backhaul (IAB) node, a low power node such as a femto, a pico, a non-terrestrial network (NTN) or non-ground network device such as a satellite network device, a low earth orbit (LEO) satellite and a geosynchronous earth orbit (GEO) satellite, an aircraft network device, and so forth, depending on the applied terminology and technology. In some example embodiments, low earth orbit (RAN) split architecture includes a Centralized Unit (CU) and a Distributed Unit (DU) . In some other example embodiments, part of the radio access network device or full of the radio access network device may embarked on an airborne or space-borne NTN vehicle.

The term “terminal device” refers to any end device that may be capable of wireless communication. By way of example rather than limitation, a terminal device may also be referred to as a communication device, user equipment (UE) , a Subscriber Station (SS) , a Portable Subscriber Station, a Mobile Station (MS) , or an Access Terminal (AT) . The terminal device may include, but not limited to, a mobile phone, a cellular phone, a smart phone, voice over IP (VoIP) phones, wireless local loop phones, a tablet, a wearable terminal device, a personal digital assistant (PDA) , portable computers, desktop computer, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback appliances, vehicle-mounted wireless terminal devices, wireless endpoints, mobile stations, laptop-embedded equipment (LEE) , laptop-mounted equipment (LME) , USB dongles, smart devices, wireless customer-premises equipment (CPE) , an Internet of Things (loT) device, a watch or other wearable, a head-mounted display (HMD) , a vehicle, a drone, a medical device and applications (e.g., remote surgery) , an industrial device and applications (e.g., a robot and/or other wireless devices operating in an industrial and/or an automated processing chain contexts) , a consumer electronics device, a device operating on commercial and/or industrial wireless networks, and the like. The terminal device may also correspond to a Mobile Termination (MT) part of an IAB node (e.g., a relay node) . In the following description, the terms “terminal device” , “communication device” , “terminal” , “user equipment” and “UE” may be used interchangeably.

As used herein, the term “resource, ” “transmission resource, ” “resource block, ” “physical resource block” (PRB) , “uplink resource, ” or “downlink resource” may refer to any resource for performing a communication, for example, a communication between a terminal device and a network device, such as a resource in time domain, a resource in frequency domain, a resource in space domain, a resource in code domain, or any other resource enabling a communication, and the like. In the following, unless explicitly stated, a resource in both frequency domain and time domain will be used as an example of a transmission resource for describing some example embodiments of the present disclosure. It is noted that example embodiments of the present disclosure are equally applicable to other resources in other domains.

FIG. 1 shows an example communication network 100 in which embodiments of the present disclosure may be implemented. As shown in FIG. 1, the communication network 100 may include a terminal device 110. Hereinafter the terminal device 110 may also be referred to as a UE.

The communication network 100 may further include a network device 120. Hereinafter the network device 120 may also be referred to as a gNB or an eNB, respectively. The network device 120 may communicate with the terminal device 110.

It is to be understood that the number of network devices and terminal devices shown in FIG. 1 is given for the purpose of illustration without suggesting any limitations. The communication network 100 may include any suitable number of network devices and terminal devices.

In some example embodiments, links from the network device 120 to the terminal device 110 may be referred to as a downlink (DL) , while links from the terminal device 110 to the network device 120 may be referred to as an uplink (UL) . In DL, the network device 120 is a transmitting (TX) device (or a transmitter) and the terminal device 110 is a receiving (RX) device (or receiver) . In UL, the terminal device 110 is a TX device (or transmitter) and the network device 120 is a RX device (or a receiver) .

Communications in the communication environment 100 may be implemented according to any proper communication protocol (s) , includes, but not limited to, cellular communication protocols of the first generation (1G) , the second generation (2G) , the third generation (3G) , the fourth generation (4G) , the fifth generation (5G) , the sixth generation (6G) , and the like, wireless local network communication protocols such as Institute for Electrical and Electronics Engineers (IEEE) 802.11 and the like, and/or any other protocols currently known or to be developed in the future. Moreover, the communication may utilize any proper wireless communication technology, includes but not limited to: Code Division Multiple Access (CDMA) , Frequency Division Multiple Access (FDMA) , Time Division Multiple Access (TDMA) , Frequency Division Duplex (FDD) , Time Division Duplex (TDD) , Multiple-Input Multiple-Output (MIMO) , Orthogonal Frequency Division Multiple (OFDM) , Discrete Fourier Transform spread OFDM (DFT-s-OFDM) and/or any other technologies currently known or to be developed in the future.

In 5G NR, two CBRA procedures are supported, namely 4-step random access procedure (i.e., RACH) and 2-step random access procedure.

For example, during a 4-step RACH, a UE may send a specific preamble in a Message 1 (MSG1) to the gNB via a physical random access channel (PRACH) using a specific resource called RACH occasion (RO) . The gNB may reply with a random access response (RAR) message, which may also be called as Message 2 (MSG2) . The MSG2 may include the detected preamble ID, the time-advance command, a Temporary Cell-Radio Network Temporary Identifier (TC-RNTI) and UL grant for the transmission of MSG3 on Physical Uplink Shared Channel (PUSCH) . Then the UE may respond to MSG2 over the scheduled PUSCH with an ID for contention resolution for a Radio Resource Control (RRC) request, which may also be called as MSG3. The gNB may transmits the contention resolution message with the contention-resolution ID for a RRC setup, which may also be referred to as a Message 4 (MSG4) .

Upon reception of the MSG4, the UE may send an ACK on a Physical Uplink Control Channel (PUCCH) if its contention-resolution ID is carried by MSG4. This completes the 4-step RACH. Furthermore, prior to MSG1, there is also a preliminary step of sending (at gNB) and receiving (at UE) the synchronization signal block (SSB) , comprising DL beam sweeping, which is not formally part of the RACH procedure. As a result of this preliminary step, the UE may select the index of the preferred SSB beam and decode the associated Physical Broadcast Channel (PBCH) for Master Information Block (MIB) , System Information Block (SIB) and so on. This index is also used by UE to identify a suitable RO for the preamble transmission (i.e., MSG1) , according to the SSB-to-RO mapping conveyed by SIB1. The gNB may use the SSB beam index selected by the UE for the MSG2 transmission.

In the 2-step random access procedure, MSG1 and MSG3 are combined in a MSGA and sent out without waiting for feedback from the gNB in between (traditionally MSG2) . Similarly, the gNB may combine MSG2 and MSG4 into Message B (MSGB) .

In the random access procedure, multiple UEs using a same preamble ID for MSG1 may use same resources to send MSG3, which may cause a decoding failure of MSG3 at gNB due to interference. Furthermore, even if the gNB successfully decodes one MSG3 and responds with the MSG4 including the contention resolution ID that was contained in the MSG3, the other UEs, whose MSG3s had not decoded by the gNB and detected unsuccessful contention resolution, may need to send MSG1 again.

Furthermore, another type of reduced capability devices that are lower-tier devices between massive IoT and Release 17 RedCap devices are introduced in Release 18. For the early identification of the RedCap devices (i.e., Release 17 RedCap devices or Release 18 RedCap devices) in MSG 1, a preamble partitioning may be used to identify different types of devices. To keep PRACH overhead to a reasonable level, the number of available preambles may be limited. As preambles are partitioned among different types of devices and use cases, this can result in greater preamble collision (i.e., multiple UEs picking the same preamble) .

Thus, if UE capability in MSG1 is identified based on partitioning of preambles for different UE types, e.g., Small Data Transmission (SDT) , RedCap, Ultra Reliable Low Latency Communication (URLLC) , RACH GROUP A, GROUP B, the number of MSG1 collisions may increase since the number of partitions of the RACH preamble space increases and the number of preambles within a partition decreases. When there is MSG1 collision from multiple UEs that selected a same PRACH preamble, the corresponding UEs may also transmit MSG3 in the same resource provided by the RAR resulting in a MSG3 contention. If the gNB is unable to decode any MSG3, it does not transmit MSG4 and hence there is no contention resolution.

Furthermore, current solutions are mostly based on early identification in MSG1 by splitting preamble space, in which resources are already very tight, and it is difficult to expand more without additional overheads. If the UEs with new features need to be identified in the future then the resources need to be further allocated. Thus, there are many shortcomings in the identification of MSG1 and it is difficult to expand further.

In this situation, a solution to address a possible MSG3 collision problem and achieve an early identification of UE types may be expected.

Therefore, the present disclosure proposes a mechanism for new MSG3/MSGA structure. In this solution, the terminal device obtains a configuration for transmitting a SRS associated with a scheduled Message3 or Message A, where the configuration corresponds to attribute information associated with the terminal device. The terminal device then transmits, to the network device, the SRS using the configuration during a random access procedure.

Example embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

Reference is now made to FIG. 2, which shows a signaling chart 200 for communication according to some example embodiments of the present disclosure. As shown in FIG. 2, the signaling chart 200 involves the terminal device 110 and the network device 120. For the purpose of discussion, reference is made to FIG. 1 to describe the signaling chart 200.

The terminal device 110 obtains a configuration for transmitting an SRS. The configuration for transmitting the SRS may correspond to attribute information associated with the terminal device 110. In some example embodiments, the attribute information associated with the terminal device 110 may comprise an identity of the terminal device 110, such as an International Mobile Subscriber Identity (IMSI) , a Temporary Mobile Subscriber Identity (TMSI) or a an initial user equipment identity.

In some example embodiments, the attribute information associated with the terminal device 110 may comprise a device type of the terminal device 110. For example, the device type of the terminal device 110 may comprise a IoT device, a RedCap device or a legacy device, etc. In some example embodiments, the attribute information associated with the terminal device 110 may also comprise capability of the terminal device.

As an option, the configuration for transmitting an SRS may be predefined, for example, in the specification, which means the terminal device 110 may obtain the configuration without receiving a signaling from the network device 120.

If the configuration for transmitting an SRS is predefined, the identity of the terminal device or a type of the terminal device binding with SRS configuration may be defined. For example, an eRedcap terminal device may use SRS resource element (RE) shift 0, an eURLLC terminal device may use SRS RE shift 1 and a SDT terminal device may use SRS RE shift 2. Alternatively, an eRedcap terminal device may use SRS Cyclic Shift (CS) 0, an eURLLC terminal device may use SRS CS 4 and a SDT terminal device may use SRS CS 8. It is also possible that the RE shift and CS may be combined into a rule for associating with the type of terminal devices.

As another option, as shown in FIG. 2, the network device 120 may transmit (202) the configuration for transmitting the SRS via, for example, a broadcasted SIB, or a RRC signaling.

In some example embodiments, the broadcasted SIB or the RRC signaling may comprise a first parameter indicating whether the SRS uses a resource element shift or a cyclic shift. It is also possible that the broadcasted SIB or the RRC signaling may comprise a second parameter in the SIB or the RRC indicating an association of the configuration with the device type of the terminal device 110 or a random selection of the configuration by the terminal device.

If the terminal device 110 is indicated that the configuration for transmitting the SRS may be randomly selected by the terminal device 110, the terminal device 110 may select the configuration based on the attribute information of the terminal device, i.e., based on an identity of the terminal device 110, a device type of the terminal device 110 or capability of the terminal device.

For example, the terminal device 110 may randomly select CS, RE shift or combine them. As another option, the terminal device 110 may randomly select the configuration corresponding to the identity of the terminal device 110, such as an IMSI, a TMSI, an initial user equipment identity or other suitable order numbers.

Furthermore, the configuration for transmitting the SRS may also indicate SRS symbol (s) position and the number of symbol (s) . For example, the SRS symbol (s) may be located at a specific position or a relative position with respect to MSG3 PUSCH last symbol. Furthermore, the symbol (s) position may be based on the coverage radius of the cell or the size of the Guard Period (GP) .

Referring back to FIG. 2, during a random access procedure, the terminal device 110 sends (204) to the network device 120 with a random access preamble. The network device 120 responds (206) a RAR (i.e., MSG2) to the terminal device 110 indicating the allocated resources for a transmission of MSG3.

In some example embodiments, the RAR may also comprise an enable-SRS indication, to indicate whether the SRS is to be transmitted by the terminal device 110 or not, because collisions in the preamble space will mostly be common during peak hours.

Alternatively, the enable-SRS indication may also be indicated to the terminal device 110 by other suitable ways. For example, the enable-SRS indication may also be indicated in a PRACH configuration or broadcasted in SIB. This may allow for minimizing overhead and improving cell edge performance outside peak hours.

If an SRS is to be transmitted after receiving the RAR, the terminal device 110 may determine whether the processing time for preparation of MSG3 is enough or not. If the processing time for preparation of MSG3 is enough, the terminal device 110 may transmit (208) the SRS associated with the MSG3. “Transmitting the SRS associated with the MSG” used hereinafter may refer to as transmitting the SRS comprised in the MSG3, or transmitting the SRS along with the MSG3” .

If the processing time for preparation of MSG3 is not enough, the terminal device 110 may transmit (208) the SRS.

If the SRS is to be transmitted associated with the MSG3, for example, the SRS may be transmitted in place of the PUSCH last symbol or after the last symbol of the PUSCH (as shown in FIGS. 3A and 3B) , which means the RAR may schedule a new MSG3 where at least 1 symbol is reserved for SRS.

FIGS. 3A and 3B show examples of a new MSG3/MSGA structure according to some example embodiments of the present disclosure. Four UEs (i.e., UEs 1, 2, 3 and 4) use the same MSG1 preamble. Then MSG2 schedules them in the same resources for MSG3 resulting in contention. The different UEs may use randomly selected SRS configurations, like random CS or RE shift. FIG. 3A shows a scenario where 12 symbols (i.e., symbols 0-11) are assigned for MSG3, which are used by each of the UEs and 1 SRS symbol (i.e., symbol 12) is configured. FIG. 3B shows another scenario where 10 symbols (i.e., symbols 0-9) are assigned for MSG3, which are used by each of the UEs, and 2 SRS symbols (i.e., symbols 11-12) are configured. It is to be understood that different UE may use different CSs and/or RE shifts.

Based on the received MSG3, the network device 120 may detect the SRS to identify how many terminal devices conflict in MSG1 and may detect any additional Timing Advance (TA) compared to initial TA based on the SRS. Then the network device 120 may send MSG4 including MAC CE backoff value for terminal device that failed contention resolution to re-transmit MSG3 with new TA. So MSG3 failed terminal devices need not send MSG1 again.

For example, as shown in FIG. 2, if the network device 120 detects that the terminal device 110 conflicts in MSG1, the network device 120 may send (210) the MSG4 including MAC CE backoff value for terminal device 110 to re-transmit MSG3 with new TA.

Reference is now made to FIG. 4, which shows a signaling chart 400 for communication according to some example embodiments of the present disclosure. As shown in FIG. 4, the signaling chart 400 involves the terminal device 110 and the network device 120. For the purpose of discussion, reference is made to FIG. 1 to describe the signaling chart 400.

In the process shown in FIG. 4, the terminal device 110 obtains a configuration for transmitting an SRS. The detail of the configuration for transmitting the SRS has already described with reference to FIG. 2, which may be omitted here.

Similarly with the process shown in FIG. 2, during a random access procedure, the terminal device 110 sends (402) to the network device 120 with a random access preamble. The network device 120 responds (404) with a RAR (i.e., MSG2) to the terminal device 110 indicating the allocated resources for a transmission of MSG3.

In some example embodiments, the RAR may also comprise an enable-SRS indication, to indicate whether the SRS is to be transmitted by the terminal device 110 or not. Alternatively, the enable-SRS indication may also be indicated to the terminal device 110 by other suitable ways. For example, the enable-SRS indication may also be indicated in a PRACH configuration or broadcasted in SIB.

Then the terminal device 110 may transmit (406) an SRS associated with the MSG3 or without the MSG3 based on the configuration. If the SRS is to be transmitted associated with the MSG3, for example, the SRS may be transmitted in place of the PUSCH last symbol or after the last symbol of the PUSCH (as shown in FIG. 5) , which means the RAR may schedule a new MSG3 where at least 1 symbol is reserved for SRS.

Based on the received SRS (s) and an association between the SRS configuration (s) and the types of terminal devices, the network device 120 may identify the types of terminal devices which send the SRS.

For example, as shown in FIG. 5, for example, in the part 501, a terminal device with type1 may send the MSG3 511 (PUSCH length 13 symbols indication by RAR) with SRS 512, where the SRS RB numbers align with MSG3 allocation.

In the part 502, a legacy terminal device may only send the MSG3 521 (PUSCH length 13 symbols indication by RAR) without SRS.

In the part 503, a terminal device with type2 may send the MSG3 531 (PUSCH length 13 symbols indication by RAR) with SRS 532, where the SRS RB numbers align with MSG3 allocation.

In the part 504, a terminal device with type4 may not send the MSG3 (PUSCH length 13 symbols indication by RAR) due to capability issue but still may send SRS 542, where the SRS RB numbers align with MSG3 allocation.

In the part 505, a terminal device with type1 may send the MSG3 551 (PUSCH length 10 symbols indication by RAR) with SRS 552, where the SRS RB numbers align with MSG3 allocation.

In the scenarios in FIG. 5, it is to be understood that UEs with different types may use different SRS configurations, such as different CSs and/or RE shifts. UEs with a same type may use a same SRS configuration.

Based on the example shown in FIG. 5, the network device 120 may detect the SRS to identify the type of terminal device that is sending the MSG3. If the network device 120 cannot decode the MSG3, since same resources are used for MSG3, the network device 120 may reschedule (for example, via transmitting (408) a MSG4) the message later based on the identification using SRS.

Based on the solution of the present disclosure, the UE identify may be achieve without further partitioning the MSG1 preambles. Furthermore, the conflict due to the MSG3 PUSCH contention may be reduced by identifying multi-user types via the SRS transmission and therefore avoid the MSG 3 failed UE to transmit the MSG1 again.

FIG. 6 shows a flowchart of an example method 600 of transmitting an SRS according to some example embodiments of the present disclosure. The method 600 may be implemented at the terminal device 110 as shown in FIG. 1. For the purpose of discussion, the method 600 will be described with reference to FIG. 1.

At 610, the terminal device 110 obtains a configuration for transmitting an SRS associated with a scheduled Message3 or Message A. The configuration for transmitting the SRS corresponds to attribute information associated with the terminal device 110.

In 620, the terminal device 110 transmits, to a network device, the SRS using the configuration during a random access procedure.

In some example embodiments, the configuration is predefined and is associated with the attribute information associated with the terminal device.

In some example embodiments, the configuration is broadcasted in a SIB or received via a RRC signaling.

In some example embodiments, the configuration is determined based on a first parameter in the SIB or the RRC indicating whether the SRS uses a resource element shift or a cyclic shift, and a second parameter in the SIB or the RRC indicating one of an association of the configuration with the device type of the terminal device, or a random selection of the configuration by the terminal device.

In some example embodiments, the terminal device may further select the configuration based on the attribute information associated with the terminal device.

In some example embodiments, the attribute information of the terminal device is associated with a resource element shift or a cyclic shift.

In some example embodiments, the attribute information comprises at least one of an identity of the terminal device, capability of the terminal device or a device type of the terminal device.

In some example embodiments, the identity of the terminal device comprises at least one of an IMSI or a TMSI or an initial user equipment identity.

In some example embodiments, the terminal device may further determine whether the SRS is to be transmitted or not based on one of at least a PRACH configuration, a Message 2 during the random access procedure, or a SIB.

In some example embodiments, the terminal device may further determine whether processing time for preparation of Message 3 is enough or not; and based on the determination of the processing time for preparation of Message 3 is enough, transmit the SRS associated with the Message 3 based on the configuration.

In some example embodiments, the terminal device may further determine whether processing time for preparation of Message 3 is enough or not; and based on the determination of the processing time for preparation of Message 3 is not enough, transmit the SRS based on the configuration.

In some example embodiments, the SRS is transmitted in a specific position of physical uplink shared channel resources allocated for the Message 3 or Message A.

In some example embodiments, the SRS is transmitted within or out of allocated resources for the transmission of the Message 3 or the Message A.

FIG. 7 shows a flowchart of an example method 700 of transmitting an SRS according to some example embodiments of the present disclosure. The method 500 may be implemented at the network device 120 as shown in FIG. 1. For the purpose of discussion, the method 700 will be described with reference to FIG. 1.

At 710, the network device 120 receives an SRS transmitted from a terminal device during the random access procedure, by using a configuration for transmitting the SRS, wherein the configuration corresponds to attribute information associated with the terminal device.

In some example embodiments, the network device may further transmit, to the terminal device, an indication indicating whether the SRS is to be transmitted or not in at least one of at least a PRACH configuration, a Message 2 during the random access procedure, or a SIB.

In some example embodiments, the network device may further receive the SRS associated with a transmission of Message 3 or Message A during a random access procedure.

In some example embodiments, the network device may further determine, based on the received SRS, the attribute information of the terminal device.

In some example embodiments, the network device may further schedule a transmission of a Message 3 or a Message A or Message 4 or a Message B based on the received SRS.

In some example embodiments, the SRS is received within or out of allocated resources for the transmission of the Message 3 or the Message A.

In some example embodiments, the apparatus comprises at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to obtain a configuration for transmitting an SRS associated with a scheduled Message3 or Message A, wherein the configuration corresponds to attribute information associated with the apparatus; and transmit, to a network device, the SRS using the configuration during a random access procedure.

In some example embodiments, the configuration is predefined and is associated with the attribute information associated with the apparatus.

In some example embodiments, the configuration is determined based on a first parameter in the SIB or the RRC indicating whether the SRS uses a resource element shift or a cyclic shift, and a second parameter in the SIB or the RRC indicating one of an association of the configuration with the device type of the apparatus, or a random selection of the configuration by the apparatus.

In some example embodiments, the apparatus is further caused to select the configuration based on the attribute information associated with the apparatus.

In some example embodiments, the attribute information of the apparatus is associated with a resource element shift or a cyclic shift.

In some example embodiments, the attribute information comprises at least one of an identity of the apparatus, capability of the apparatus or a device type of the apparatus.

In some example embodiments, the identity of the apparatus comprises at least one of an IMSI or a TMSI or an initial user equipment identity.

In some example embodiments, the apparatus is further caused to determine whether the SRS is to be transmitted or not based on one of at least a PRACH configuration, a Message 2 during the random access procedure, or a SIB.

In some example embodiments, the apparatus is further caused to determine whether processing time for preparation of Message 3 is enough or not; and based on the determination of the processing time for preparation of Message 3 is enough, transmit the SRS associated with the Message 3 based on the configuration.

In some example embodiments, the apparatus is further caused to determine whether processing time for preparation of Message 3 is enough or not; and based on the determination of the processing time for preparation of Message 3 is not enough, transmit the SRS based on the configuration.

In some example embodiments, the apparatus comprises at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to receive an SRS transmitted from a terminal device during the random access procedure, by using a configuration for transmitting the SRS, wherein the configuration corresponds to attribute information associated with the terminal device.

In some example embodiments, the apparatus is further caused to transmit, to the terminal device, an indication indicating whether the SRS is to be transmitted or not in at least one of at least a PRACH configuration, a Message 2 during the random access procedure, or a SIB.

In some example embodiments, the apparatus is further caused to receive the SRS associated with a transmission of Message 3 or Message A during a random access procedure.

In some example embodiments, the apparatus is further caused to determine, based on the received SRS, the attribute information of the terminal device.

In some example embodiments, the apparatus is further caused to schedule a transmission of a Message 3 or a Message A or Message 4 or a Message B based on the received SRS.

In some example embodiments, an apparatus capable of performing the method 600 (for example, implemented at the terminal device 110) may include means for performing the respective steps of the method 600. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

In some example embodiments, the apparatus comprises means for obtaining a configuration for transmitting an SRS associated with a scheduled Message3 or Message A, wherein the configuration corresponds to attribute information associated with the apparatus; and means for transmitting, to a network device, the SRS using the configuration during a random access procedure.

In some example embodiments, the apparatus comprises means for selecting the configuration based on the attribute information associated with the apparatus.

In some example embodiments, the apparatus comprises means for determining whether the SRS is to be transmitted or not based on one of at least a PRACH configuration, a Message 2 during the random access procedure, or a SIB.

In some example embodiments, the apparatus comprises means for determining whether processing time for preparation of Message 3 is enough or not; and based on the determination of the processing time for preparation of Message 3 is enough, transmit the SRS associated with the Message 3 based on the configuration.

In some example embodiments, the apparatus comprises means for determining whether processing time for preparation of Message 3 is enough or not; and based on the determination of the processing time for preparation of Message 3 is not enough, transmit the SRS based on the configuration.

In some example embodiments, an apparatus capable of performing the method 700 (for example, implemented at the network device 120) may include means for performing the respective steps of the method 700. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

In some example embodiments, the apparatus comprises means for receiving an SRS transmitted from a terminal device during the random access procedure, by using a configuration for transmitting the SRS, wherein the configuration corresponds to attribute information associated with the terminal device.

In some example embodiments, the apparatus comprises means for transmitting, to the terminal device, an indication indicating whether the SRS is to be transmitted or not in at least one of at least a PRACH configuration, a Message 2 during the random access procedure, or a SIB.

In some example embodiments, the apparatus comprises means for receiving the SRS associated with a transmission of Message 3 or Message A during a random access procedure.

In some example embodiments, the apparatus comprises means for determining, based on the received SRS, the attribute information of the terminal device.

In some example embodiments, the apparatus comprises means for scheduling a transmission of a Message 3 or a Message A or Message 4 or a Message B based on the received SRS.

FIG. 8 is a simplified block diagram of a device 800 that is suitable for implementing example embodiments of the present disclosure. The device 800 may be provided to implement a communication device, for example, the terminal device 110 or the network device 120 as shown in FIG. 1. As shown, the device 800 includes one or more processors 810, one or more memories 820 coupled to the processor 810, and one or more communication modules 840 coupled to the processor 810.

The communication module 840 is for bidirectional communications. The communication module 840 has one or more communication interfaces to facilitate communication with one or more other modules or devices. The communication interfaces may represent any interface that is necessary for communication with other network elements. In some example embodiments, the communication module 840 may include at least one antenna.

The processor 810 may be of any type suitable to the local technical network and may include one or more of the following: general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 800 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

The memory 820 may include one or more non-volatile memories and one or more volatile memories. Examples of the non-volatile memories include, but are not limited to, a Read Only Memory (ROM) 824, an electrically programmable read only memory (EPROM) , a flash memory, a hard disk, a compact disc (CD) , a digital video disk (DVD) , an optical disk, a laser disk, and other magnetic storage and/or optical storage. Examples of the volatile memories include, but are not limited to, a random access memory (RAM) 822 and other volatile memories that will not last in the power-down duration.

A computer program 830 includes computer executable instructions that are executed by the associated processor 810. The instructions of the program 830 may include instructions for performing operations/acts of some example embodiments of the present disclosure. The program 830 may be stored in the memory, e.g., the ROM 824. The processor 810 may perform any suitable actions and processing by loading the program 830 into the RAM 822.

The example embodiments of the present disclosure may be implemented by means of the program 830 so that the device 800 may perform any process of the disclosure as discussed with reference to FIG. 2 to FIG. 7. The example embodiments of the present disclosure may also be implemented by hardware or by a combination of software and hardware.

In some example embodiments, the program 830 may be tangibly contained in a computer readable medium which may be included in the device 800 (such as in the memory 820) or other storage devices that are accessible by the device 800. The device 800 may load the program 830 from the computer readable medium to the RAM 822 for execution. In some example embodiments, the computer readable medium may include any types of non-transitory storage medium, such as ROM, EPROM, a flash memory, a hard disk, CD, DVD, and the like. The term “non-transitory, ” as used herein, is a limitation of the medium itself (i.e., tangible, not a signal) as opposed to a limitation on data storage persistency (e.g., RAM vs. ROM) .

FIG. 9 shows an example of the computer readable medium 900 which may be in form of CD, DVD or other optical storage disk. The computer readable medium 900 has the program 830 stored thereon.

Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representations, it is to be understood that the block, apparatus, system, technique or method described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

Some example embodiments of the present disclosure also provide at least one computer program product tangibly stored on a computer readable medium, such as a non-transitory computer readable medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target physical or virtual processor, to carry out any of the methods as described above. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. The program code may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program code, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

In the context of the present disclosure, the computer program code or related data may be carried by any suitable carrier to enable the device, apparatus or processor to perform various processes and operations as described above. Examples of the carrier include a signal, computer readable medium, and the like.

The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A computer readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the computer readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM) , a read-only memory (ROM) , an erasable programmable read-only memory (EPROM or Flash memory) , an optical fiber, a portable compact disc read-only memory (CD-ROM) , an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Unless explicitly stated, certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, unless explicitly stated, various features that are described in the context of a single embodiment may also be implemented in a plurality of embodiments separately or in any suitable sub-combination.

Although the present disclosure has been described in languages specific to structural features and/or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

An apparatus comprising:

at least one processor; and

at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to:

obtain a configuration for transmitting a sounding reference signal, SRS, associated with a scheduled Message3 or Message A, wherein the configuration corresponds to attribute information associated with the apparatus; and

transmit, to a network device, the SRS using the configuration during a random access procedure.
The apparatus of claim 1, wherein the configuration is predefined and is associated with the attribute information associated with the apparatus.
The apparatus of claim 1, wherein the configuration is broadcasted in a system information block, SIB or received via a Radio Resource Control, RRC.
The apparatus of claim 3, wherein the configuration is determined based on a first parameter in the SIB or the RRC indicating whether the SRS uses a resource element shift or a cyclic shift, and a second parameter in the SIB or the RRC indicating one of:

an association of the configuration with a device type of the apparatus, or

a random selection of the configuration by the apparatus.
The apparatus of any of claims 1-4, wherein the apparatus is caused to:

select the configuration based on the attribute information associated with the apparatus.
The apparatus of any of claims 1-5, wherein the attribute information of the apparatus is associated with a resource element shift or a cyclic shift.
The apparatus of any of claims 1-6, wherein the attribute information comprises at least one of an identity of the apparatus, capability of the apparatus or a device type of the apparatus.
The apparatus of claim 7, wherein the identity of the apparatus comprises at least one of an International Mobile Subscriber Identity, IMSI, of the apparatus, or a Temporary Mobile Subscriber Identity, TMSI, of the apparatus, or an initial user equipment identity of the apparatus.
The apparatus of claim 1, wherein the apparatus is caused to:

determine whether the SRS is to be transmitted or not based on one of at least:

a physical random access channel, PRACH, configuration,

a Message 2 during the random access procedure, or

a system information block.
The apparatus of any of claims 1-9, wherein the apparatus is caused to:

determine whether processing time for preparation of Message 3 is enough or not; and

based on the determining that the processing time for preparation of Message 3 is enough, transmit the SRS associated with the Message 3 based on the configuration.
The apparatus of any of claims 1-9, wherein the apparatus is caused to:

determine whether processing time for preparation of Message 3 is enough or not; and

based on the determining that the processing time for preparation of Message 3 is not enough, transmit the SRS based on the configuration.
The apparatus of any of claims 1-11, wherein the SRS is transmitted in a specific position of physical uplink shared channel resources allocated for the Message 3 or Message A.
The apparatus of any of claims 1-11, wherein the SRS is transmitted within or outside allocated resources for the transmission of the Message 3 or the Message A.
An apparatus comprising:

at least one processor; and

at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to:

receive a sounding reference signal, SRS, transmitted from a terminal device during a random access procedure, by using a configuration for transmitting the SRS, wherein the configuration corresponds to attribute information associated with the terminal device.
The apparatus of claim 14, wherein the configuration is predefined and is associated with the attribute information associated with the terminal device.
The apparatus of claim 14, wherein the configuration is broadcasted in a system information block, SIB or received via RRC.
The apparatus of claim 16, wherein the configuration is determined based on a first parameter in the SIB or the RRC indicating whether the SRS uses a resource element shift or a cyclic shift, and a second parameter in the SIB or the RRC indicating one of:

an association of the configuration with a device type of the terminal device, or

a random selection of the configuration by the terminal device.
The apparatus of any of claims 14-17, wherein the attribute information of the terminal device is associated with a resource element shift or a cyclic shift.
The apparatus of any of claims 14-18, wherein the attribute information comprises at least one of an identity of the terminal device, capability of the terminal device or a device type of the terminal device.
The apparatus of claim 19, wherein the identity of the terminal device comprises at least one of an International Mobile Subscriber Identity, IMSI, of the terminal device, or a Temporary Mobile Subscriber Identity, TMSI, of the terminal device, or an initial user equipment identity, of the terminal device.
The apparatus of claim 14, wherein the apparatus is caused to:

transmit, to the terminal device, an indication indicating whether the SRS is to be transmitted or not in one of at least:

a physical random access channel, PRACH, configuration,

a Message 2 during a random access procedure, or

a system information block.
The apparatus of claim 14, wherein the apparatus is caused to:

receive the SRS associated with a transmission of Message 3 or Message A during a random access procedure.
The apparatus of claim 14, wherein the apparatus is caused to:

determine, based on the received SRS, the attribute information of the terminal device.
The apparatus of any of claims 14-23, wherein the apparatus is caused to:

schedule a transmission of a Message 3 or a Message A or Message 4 or a Message B based on the received SRS.
The apparatus of any of claims 14-25, wherein the SRS is received within or outside allocated resources for the transmission of the Message 3 or the Message A.
A method comprising:

obtaining, by a terminal device, a configuration for transmitting a sounding reference signal, SRS, associated with a scheduled Message3 or Message A, wherein the configuration corresponds to attribute information associated with the terminal device; and

transmitting, by the terminal device and to a network device, the SRS using the configuration during a random access procedure.
A method comprising:

receiving, by a network device, a sounding reference signal, SRS, transmitted from a terminal device during a random access procedure, by using a configuration for transmitting the SRS, wherein the configuration corresponds to attribute information associated with the terminal device.
An apparatus comprising:

means for obtaining a configuration for transmitting a sounding reference signal, SRS, associated with a scheduled Message3 or Message A, wherein the configuration corresponds to attribute information associated with the apparatus; and

means for transmitting, to a network device, the SRS using the configuration during a random access procedure.
An apparatus comprising:

means for receiving a sounding reference signal, SRS, transmitted from a terminal device during a random access procedure, by using a configuration for transmitting the SRS, wherein the configuration corresponds to attribute information associated with the terminal device.
A non-transitory computer readable medium comprising program instructions that, when executed by an apparatus, cause the apparatus at least to:

obtain a configuration for transmitting a sounding reference signal, SRS, associated with a scheduled Message3 or Message A, wherein the configuration corresponds to attribute information associated with the apparatus; and

transmit, to a network device, the SRS using the configuration during a random access procedure.
A non-transitory computer readable medium comprising program instructions that, when executed by an apparatus, cause the apparatus at least to:

receive a sounding reference signal, SRS, transmitted from a terminal device during a random access procedure, by using a configuration for transmitting the SRS, wherein the configuration corresponds to attribute information associated with the terminal device.