HK1243267B - Device and method to improve horizontal and vertical positioning accuracy - Google Patents

Description

Device and method for improving horizontal and vertical positioning accuracy

Priority claim

This application claims priority to U.S. Provisional Patent Application No. 62/107,665, filed on January 26, 2015, entitled “RAN1/RAN2: METHOD TO IMPROVE THE POSITIONING ACCURACY IN HORIZONTAL AND VERTICAL DOMAIN,” which is hereby incorporated by reference in its entirety.

Technical Field

Embodiments relate to radio access networks. Some embodiments relate to determining location in cellular networks, including Third Generation Partnership Project Long Term Evolution (3GPP LTE) networks and LTE-Advanced (LTE-A) networks, as well as fourth generation (4G) networks and fifth generation (5G) networks.

Background Art

Over the past two decades, the use of personal communication devices has seen tremendous growth. The penetration of mobile devices (user equipment, or UE) in modern society continues to drive demand for a wide variety of connected devices in many different environments. The use of connected UEs utilizing 3GPP systems has increased in all aspects of home and work life. An increasing number of mobile services require accurately determining the UE's location. One of the most common positioning methods is through the use of the Global Positioning System (GPS) or the Global Navigation Satellite System (GNSS). In addition to providing positioning for commercial and personal applications, GPS/GNSS-enabled UEs may also be used by emergency services to obtain information about the UE's location as part of emergency call processing (E911 services). Although location determination for E911 services is mandated by the Federal Communications Commission (FCC), in many cases, location determination based on satellite (GPS/GNSS) signals is ineffective. Specifically, in certain areas, GPS or GNSS is unavailable due to obstruction of satellite signals, such as inside buildings or other areas where the UE cannot detect signals from a sufficient number of satellites. This problem is only likely to worsen as FCC guidelines become more stringent, with the FCC currently requiring location accuracy of 50 meters for 67% of outdoor E911 communications and 150 meters for 80% (rising to 90% by 2020). Furthermore, the FCC is proposing to extend E911 location determination to indoor locations and also require vertical location information within 3 meters of the caller for 67% (rising to 80% by 2020) of indoor E911 communications.

The latest version (Release 13) of the 3GPP standard for Long Term Evolution (LTE) networks contains updated requirements for position determination that are difficult to meet given the current positioning capabilities of the network. Thus, there is a need to improve positioning accuracy and enable vertical domain positioning of UEs.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings, like reference numerals may describe similar components in different views, wherein the drawings are not necessarily drawn to scale. Like reference numerals with different letter subscripts may represent different instances of similar components. The accompanying drawings generally illustrate the various embodiments discussed in this document by way of example and not limitation.

FIG1 is a functional diagram of a 3GPP network according to some embodiments.

FIG2 illustrates components of a UE according to some embodiments.

3A-D illustrate downlink channel resource blocks containing PRS according to some embodiments.

FIG4 illustrates ASN.1 code for configuring multiple PRS configurations according to some embodiments.

FIG5 illustrates UE position determination in the horizontal and vertical domains according to some embodiments.

FIG6 illustrates vertical UE position determination using multiple reference signal configurations according to some embodiments.

FIG7 shows a flow chart for determining a UE location according to some embodiments.

FIG8 is a block diagram of a communication device according to some embodiments.

FIG9 illustrates a block diagram of an example machine according to some embodiments.

DETAILED DESCRIPTION

The following description and accompanying drawings sufficiently illustrate the specific embodiments to enable those skilled in the art to practice these embodiments. Other embodiments may include structural variations, logical variations, electrical variations, process variations, and other variations. Components and features of some embodiments may be included in or substituted for components and features of other embodiments. The embodiments set forth in the claims include all available equivalents of those claims.

Figure 1 shows an example of a portion of an end-to-end network architecture of a Long Term Evolution (LTE) network with various components of the network according to some embodiments. As used herein, LTE and LTE-A networks and devices (including 3G, 4G, and 5G networks and devices) are referred to solely as LTE networks and devices. Network 100 may include a radio access network (RAN) (e.g., E-UTRAN or Evolved Universal Terrestrial Radio Access Network, as shown) 101 and a core network 120 (e.g., shown as an Evolved Packet Core (EPC)) coupled together via an S1 interface 115. For convenience and brevity, only a portion of the core network 120 and the RAN 101 are shown in the example.

The core network 120 may include a mobility management entity (MME) 122, a serving gateway (serving GW) 124, and a packet data network gateway (PDN GW) 126. The RAN includes an enhanced Node B (eNB) 104 (which may operate as a base station) for communicating with a user equipment (UE) 102. The eNB 104 may include a macro eNB and a low power (LP) eNB. The eNB 104 and the UE 102 may utilize positioning reference signals (PRS) as described herein to achieve position determination.

The MME 122 can be functionally similar to the control plane of a legacy Serving GPRS Support Node (SGSN). The MME can manage mobility aspects of access, such as gateway selection and tracking area list management. The Serving GW 124 can terminate the interface toward the RAN 101 and route data packets between the RAN 101 and the core network 120. Furthermore, the Serving GW 124 can serve as the local mobility anchor for handovers between eNBs and can also provide an anchor for inter-3GPP mobility. Other responsibilities may include lawful interception, charging, and some policy enforcement. The Serving GW 124 and the MME 122 can be implemented in one physical node or in separate physical nodes. The PDN GW 126 can terminate the SGi interface toward the packet data network (PDN). The PDN GW 126 can route data packets between the EPC 120 and external PDNs and can be a key node for policy enforcement and charging data collection. The PDN GW 126 can also provide an anchor for mobility using non-LTE accesses. The external PDN may be any type of IP network, as well as an IP Multimedia Subsystem (IMS) domain. The PDN GW 126 and the serving gateway 124 may be implemented in one physical node or in separate physical nodes.

The PDN GW 126 and the MME 122 may also be connected to a location server 130. The UE and the eNB may communicate with the location server 130 via the user plane (U-Plane) and/or the control plane (C-Plane), respectively. The location server 130 may be a physical or logical entity that collects measurement data and other location information from the UE 102 and the eNB 104 and helps the UE 102 estimate its location, providing network-based location calculations, as will be described in more detail below. Specifically, the UE 102 may be connected to the eNB 104. The eNB 104 may be connected to the MME 122 via the control plane, which in turn may be connected to the evolved serving mobile location center (E-SMLC) 134 of the location server 130. The eNB 104 may also be connected to the secure user plane (SUPL) location platform (SLP) 132 of the location server 130 via the user plane through the PDN GW 126. SLP 132 of location server 130 may provide information to UE 102 through PDN GW 126 .

The eNB 104 (macro and micro eNBs) can terminate the air interface protocol and can be the first point of contact for the UE 102. In some embodiments, the eNB 104 can implement various logical functions for the RAN 101, including but not limited to RNC (Radio Network Controller) functions, such as radio bearer management, uplink and downlink dynamic radio resource management and data packet scheduling, and mobility management. According to an embodiment, the UE 102 can be configured to transmit orthogonal frequency division multiplexing (OFDM) communication signals with the eNB 104 on a multi-carrier communication channel according to OFDMA communication technology. OFDM signals can include multiple orthogonal subcarriers. Each eNB 104 can send a reconfiguration message to each UE 102 connected to the eNB 104. The reconfiguration message can include reconfiguration information, which includes one or more parameters indicating specific information about reconfiguring the UE 102 in mobility scenarios (e.g., handover) to reduce the delay involved in the handover. These parameters can include physical layer and layer 2 reconfiguration indicators, as well as security key update indicators. These parameters can be used to instruct UE 102 to avoid or skip one or more of the indicated processes to reduce messaging between UE 102 and the network. The network can automatically route packet data between UE 102 and the new eNB 104 and can provide required information between the eNBs 104 involved in the move. However, the present application is not limited thereto, and additional embodiments will be described in more detail below.

The S1 interface 115 is an interface that separates the RAN 101 from the EPC 120. The S1 interface 115 can be divided into two parts: the S1-U, which carries traffic data between the eNB 104 and the Serving GW 124, and the S1-MME, which serves as the signaling interface between the eNB 104 and the MME 122. The X2 interface is an interface between eNBs 104. The X2 interface can include two parts: X2-C and X2-U. X2-C can be a control plane interface between eNBs 104, while X2-U can be a user plane interface between eNBs 104.

With cellular networks, LP cells can be used to extend coverage to indoor areas where outdoor signals don't reach well, or to increase network capacity in areas with high phone usage, such as train stations. As used herein, the term low-power (LP) eNB can refer to any suitable lower-power eNB for implementing narrower cells (narrower than macrocells), such as femtocells, picocells, or microcells. Femtocell eNBs may be typically provided by mobile network operators to their residential or enterprise customers. Femtocells may typically be the size of a residential gateway or smaller and are typically connected to the user's broadband line. Once plugged in, the femtocell can connect to the mobile operator's mobile network and provide additional coverage to residential femtocells, typically within a range of 30 to 50 meters. Thus, an LP eNB may be a femto eNB because it is coupled through a PDN GW 126. Similarly, a picocell may be a wireless communication system that typically covers a small area, such as within a building (office, shopping mall, train station, etc.) or, more recently, within an aircraft. A picocell eNB can typically connect to another eNB (e.g., a macro eNB) via an X2 link through its base station controller (BSC) functionality. Thus, a low-end eNB can be implemented as a picocell eNB, as it is coupled to the macro eNB via the X2 interface. A picocell eNB or other low-end eNB can include some or all of the functionality of a macro eNB. In some cases, this may be referred to as an access point base station or an enterprise femtocell.

Other wireless communication devices may exist within the same geographic area as RAN 101. As shown in FIG1 , WLAN devices include one or more access points (APs) 103 and one or more stations (STAs) 105 communicating with AP 103. WLAN devices may communicate using one or more IEEE 802.11 protocols, such as IEEE 802.11a/b/n/ac. Because the power of WLAN devices 103 and 105 may be very limited, they may be geographically localized compared to eNB 104.

Communications on an LTE network can be divided into 10ms frames, each containing ten 1ms subframes. Each subframe can contain two 0.5ms time slots. Depending on the system used, each time slot can contain 6-7 symbols. A resource block (RB) (also known as a physical resource block (PRB)) can be the smallest unit of resources that can be allocated to a UE 102. A resource block can be 180kHz wide in frequency and 1 time slot long in time. In frequency, a resource block can be as wide as 12×15kHz subcarriers or 24×7.5kHz subcarriers. For most channels and signals, 12 subcarriers can be used per resource block. In frequency division duplex (FDD) mode, uplink and downlink frames can be 10ms and can be separated in frequency (full duplex) or time (half duplex). In a time division duplex (TDD) structure, uplink and downlink subframes can be transmitted on the same frequency and can be multiplexed in the time domain. The downlink resource grid can be used for downlink transmission from the eNB to the UE. The grid can be a time-frequency grid, which is the physical resource in the downlink in each time slot. Each column and each row of the resource grid can correspond to an OFDM symbol and an OFDM subcarrier, respectively. The duration of the resource grid in the time domain can correspond to a time slot. The smallest time-frequency unit in the resource grid can be represented as a resource unit. Each resource grid may include multiple resource blocks as described above, which describe the mapping relationship between specific network channels and resource units. Each resource block may include 12 (subcarriers) × 14 (symbols) = 168 resource units.

There may be several different physical downlink channels that are transmitted using such resource blocks. Two of these physical downlink channels may be the physical downlink control channel (PDCCH) and the physical downlink shared channel (PDSCH). Each subframe may be divided into the PDCCH and the PDSCH. The PDCCH may normally occupy the first two symbols of each subframe and carry information regarding the transport format and resource allocation associated with the PDSCH channel, as well as H-ARQ information associated with the uplink shared channel. The PDSCH may carry user data and higher-layer signaling for the UE 102 and occupies the remainder of the subframe. Typically, downlink scheduling (allocation of control and shared channel resource blocks to UEs 102 within a cell) may be performed at the eNB 104 based on channel quality information provided from the UE 102 to the eNB. Downlink resource allocation information may then be sent to each UE 102 on the PDCCH for (allocated to) that UE. A transmission time interval (TTI) may be the smallest unit of time in which the eNB 104 can schedule a UE 102 for uplink or downlink transmissions. The PDCCH may contain downlink control information (DCI) from the resource grid transmitted on the PDSCH in the same subframe, in one of several formats that tells the UE 102 how to find and decode the data. The DCI format may provide details such as the number of resource blocks, resource allocation type, modulation scheme, transport block, redundancy version, coding rate, etc. Each DCI format may have a cyclic redundancy code (CRC) and may be scrambled with a radio network temporary identifier (RNTI) that identifies the target UE 102 for the PDSCH. Using a UE 102-specific RNTI may restrict decoding of the DCI format (and corresponding PDSCH) to only the intended UE 102.

Similarly, an uplink subframe may include a physical uplink shared channel (PUSCH) and a physical uplink control channel (PUCCH) with a physical random access channel (PRACH). The PUCCH may provide various control signals, including HARQ acknowledgements/non-acknowledgements, one or more channel quality indicators (CQIs), MIMO feedback (rank indicator (RI); precoding matrix indicator (PMI), and scheduling requests for uplink transmissions. The PUCCH may be transmitted in a frequency region at the edge of the system bandwidth and may include one RB per transmission at one end of the system bandwidth, followed by an RB in the next slot at the opposite end of the channel spectrum, thereby utilizing frequency diversity. The PUCCH control region may include every two RBs. BPSK or QPSK may be used to modulate the PUCCH information. The PRACH may be used for random access and consists of two sequences: a cyclic prefix and a guard period. The preamble sequence may be repeated to enable the eNB to decode the preamble sequence under poor link conditions. The PMI is used for precoding, where beams of several layers are formed to improve reception quality for those layers, taking into account the characteristics of the transmission channel. The eNB 104 can measure the channel and inform the UE 102 of the precoder to use the appropriate precoding mechanism, which allows the UE 102 to perform precoding based on this information. The precoder can be represented by a matrix (i.e., a precoding matrix) where the number of matrix rows is equal to the number of antennas and the number of matrix columns is equal to the number of layers.

The embodiments described herein can be implemented in a system using any appropriately configured hardware and/or software. FIG2 illustrates components of a UE according to some embodiments. At least some of the components shown may be used in an eNB or MME, such as UE 102 or eNB 104 shown in FIG1 . UE 200 and other components may be configured to determine UE location using positioning reference signals (PRS) as described herein. UE 200 may be one of UE 102 shown in FIG1 and may be a stationary, non-mobile device or a mobile device. In some embodiments, UE 200 may include application circuitry 202, baseband circuitry 204, radio frequency (RF) circuitry 206, front-end module (FEM) circuitry 208, and one or more antennas 210, coupled together at least as shown. At least some of baseband circuitry 204, RF circuitry 206, and FEM circuitry 208 may form a transceiver. In some embodiments, other network elements, such as an eNB, may include some or all of the components shown in FIG2 . Other network elements such as the MME may include an interface (eg, an S1 interface) to communicate with the eNB over a wired connection with the UE.

The application or processing circuitry 202 may include one or more application processors. For example, the application circuitry 202 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The processors may include any combination of general-purpose processors and specialized processors (e.g., graphics processors, application processors, etc.). The processors may be coupled to and/or include memory/storage devices and may be configured to execute instructions stored in the memory/storage devices to enable various applications and/or operating systems to run on the system.

The baseband circuitry 204 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The baseband circuitry 204 may include one or more baseband processors and/or control logic to process baseband signals received from the receive signal path of the RF circuitry 206 and generate baseband signals for the transmit signal path of the RF circuitry. The baseband processing circuitry 204 may interface with the application circuitry 202 to generate and process baseband signals and control the operation of the RF circuitry 206. For example, in some embodiments, the baseband circuitry 204 may include a second-generation (2G) baseband processor 204a, a third-generation (3G) baseband processor 204b, a fourth-generation (4G) baseband processor 204c, and/or processors for other existing, developing, or future generations (e.g., fifth-generation (5G), 6G, etc.). The baseband circuitry 204 (e.g., one or more of the baseband processors 204a-d) may handle various radio control functions that enable communication with one or more radio networks via the RF circuitry 206. The radio control functions may include, but are not limited to, signal modulation/demodulation, encoding/decoding, radio frequency offset, etc. In some embodiments, the modulation/demodulation circuitry of baseband circuitry 204 may include fast Fourier transform (FFT), precoding, and/or constellation mapping/demapping functionality. In some embodiments, the encoding/decoding circuitry of baseband circuitry 204 may include convolution, tail-biting convolution, turbo, Viterbi, and/or low-density parity check (LDPC) encoder/decoder functionality. The embodiments of the modulation/demodulation and encoder/decoder functionality are not limited to these examples and may include other suitable functionality in other embodiments.

In some embodiments, the baseband circuitry 204 may include elements of a protocol stack, such as elements of the Evolved Universal Terrestrial Radio Access Network (EUTRAN) protocol, including, for example, physical (PHY), medium access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), and/or radio resource control (RRC) elements. The central processing unit (CPU) 204e of the baseband circuitry 204 may be configured to run the elements of the protocol stack to implement signaling transmission at the PHY, MAC, RLC, PDCP, and/or RRC layers. In some embodiments, the baseband circuitry may include one or more audio digital signal processors (DSPs) 204f. In other embodiments, the audio DSPs 204f may include elements for compression/decompression and echo cancellation and may include other suitable processing elements. In some embodiments, the components of the baseband circuitry may be appropriately combined in a single chip, a single chipset, or provided on the same circuit board. In some embodiments, some or all of the components of the baseband circuitry 204 and the application circuitry 202 may be implemented together, for example, on a system on a chip (SOC).

In some embodiments, the baseband circuitry 204 can provide communications compatible with one or more radio technologies. For example, in some embodiments, the baseband circuitry 204 can support communications with the Evolved Universal Terrestrial Radio Access Network (EUTRAN) and/or other Wireless Metropolitan Area Networks (WMANs), Wireless Local Area Networks (WLANs), and Wireless Personal Area Networks (WPANs). Embodiments in which the baseband circuitry 204 is configured to support radio communications of more than one wireless protocol may be referred to as multi-mode baseband circuitry. In some embodiments, the device can be configured to operate in accordance with communication standards or other protocols or standards, including Institute of Electrical and Electronics Engineers (IEEE) 802.16 wireless technology (WiMax), IEEE 802.11 wireless technology (WiFi) including IEEE 802ad operating on the 60 GHz millimeter wave spectrum, various other wireless technologies, such as Global System for Mobile Communications (GSM), Enhanced Data Rates for GSM Evolution (EDGE), GSM EDGE Radio Access Network (GERAN), Universal Mobile Telecommunications System (UMTS), UMTS Terrestrial Radio Access Network (UTRAN), or other 2G, 3G, 4G, 5G, etc. technologies that have been developed or will be developed.

RF circuitry 206 can enable communication with a wireless network using modulated electromagnetic radiation through a non-solid medium. In various embodiments, RF circuitry 206 can include switches, filters, amplifiers, etc. to facilitate communication with the wireless network. RF circuitry 206 can include a receive signal path, which can include circuitry for down-converting RF signals received from FEM circuitry 208 and providing a baseband signal to baseband circuitry 204. RF circuitry 206 can also include a transmit signal path, which can include circuitry for up-converting baseband signals provided by baseband circuitry 204 and providing an RF output signal to FEM circuitry 208 for transmission.

In some embodiments, RF circuitry 206 may include a receive signal path and a transmit signal path. The receive signal path of RF circuitry 206 may include mixer circuitry 206a, amplifier circuitry 206b, and filter circuitry 206c. The transmit signal path of RF circuitry 206 may include filter circuitry 206c and mixer circuitry 206a. RF circuitry 206 may also include synthesizer circuitry 206d for synthesizing frequencies for use by mixer circuitry 206a in both the receive and transmit signal paths. In some embodiments, mixer circuitry 206a in the receive signal path may be configured to downconvert the RF signal received from FEM circuitry 208 based on the synthesized frequency provided by synthesizer circuitry 206d. Amplifier circuitry 206b may be configured to amplify the downconverted signal, and filter circuitry 206c may be a low-pass filter (LPF) or a band-pass filter (BPF) configured to remove unwanted signals from the downconverted signal to generate an output baseband signal. The output baseband signal may be provided to baseband circuitry 204 for further processing. In some embodiments, the output baseband signal may be a zero-frequency baseband signal, but this is not required. In some embodiments, the mixer circuit 206a of the receive signal path may include a passive mixer, but the scope of the embodiments is not limited in this regard.

In some embodiments, mixer circuit 206 a of the transmit signal path can be configured to up-convert an input baseband signal based on a synthesized frequency provided by synthesizer circuit 206 d to generate an RF output signal for FEM circuit 208. The baseband signal can be provided by baseband circuit 204 and can be filtered by filter circuit 206 c. Filter circuit 206 c can include a low-pass filter (LPF), but the scope of the embodiments is not limited in this respect.

In some embodiments, the mixer circuit 206a of the receive signal path and the mixer circuit 206a of the transmit signal path may include two or more mixers and may be arranged to perform quadrature down-conversion and up-conversion, respectively. In some embodiments, the mixer circuit 206a of the receive signal path and the mixer circuit 206a of the transmit signal path may include two or more mixers and may be arranged to perform image rejection (e.g., Hartley image rejection). In some embodiments, the mixer circuit 206a of the receive signal path and the mixer circuit 206a of the transmit signal path may be arranged to perform direct down-conversion and/or direct up-conversion, respectively. In some embodiments, the mixer circuit 206a of the receive signal path and the mixer circuit 206a of the transmit signal path may be configured to perform superheterodyne operation.

In some embodiments, the output baseband signal and the input baseband signal may be analog baseband signals, but the scope of the embodiments is not limited in this respect. In some alternative embodiments, the output baseband signal and the input baseband signal may be digital baseband signals. In these alternative embodiments, RF circuitry 206 may include analog-to-digital converter (ADC) and digital-to-analog converter (DAC) circuitry, and baseband circuitry 204 may include a digital baseband interface to communicate with RF circuitry 206.

In some dual-mode embodiments, separate radio IC circuitry may be provided for processing signals for each spectrum, although the scope of the embodiments is not limited in this regard.

In some embodiments, synthesizer circuit 206 d may be a fractional-N synthesizer or a fractional-N/N+1 synthesizer, but the scope of the embodiments is not limited in this respect, as other types of frequency synthesizers may also be suitable. For example, synthesizer circuit 206 d may be a delta-sigma synthesizer, a frequency multiplier, or a synthesizer including a phase-locked loop with a frequency divider.

Synthesizer circuit 206d may be configured to synthesize an output frequency based on the frequency input and the divider control input for use by mixer circuit 206a of RF circuit 206. In some embodiments, synthesizer circuit 206d may be a fractional-N/N+1 synthesizer.

In some embodiments, the frequency input may be provided by a voltage-controlled oscillator (VCO), but this is not required. Depending on the desired output frequency, the divider control input may be provided by baseband circuitry 204 or application processor 202. In some embodiments, the divider control input (e.g., N) may be determined from a lookup table based on the channel indicated by application processor 202.

The synthesizer circuit 206d of the RF circuit 206 may include a frequency divider, a delay-locked loop (DLL), a multiplexer, and a phase accumulator. In some embodiments, the frequency divider may be a dual-modulus divider (DMD) and the phase accumulator may be a digital phase accumulator (DPA). In some embodiments, the DMD may be configured to divide the input signal by N or N+1 (e.g., based on the implementation) to provide a fractional division ratio. In some example embodiments, the DLL may include a set of cascaded tunable delay elements, a phase detector, a charge pump, and a D-type flip-flop. In these embodiments, the delay elements may be configured to divide the VCO cycle into Nd equal phase packets, where Nd is the number of delay elements in the delay line. In this way, the DLL provides negative feedback to help ensure that the total delay through the delay line is one VCO cycle.

In some embodiments, synthesizer circuit 206 d can be configured to generate a carrier frequency as an output frequency, but in other embodiments, the output frequency can be a multiple of the carrier frequency (e.g., twice the carrier frequency, four times the carrier frequency) and combined with quadrature generator and divider circuits to generate multiple signals at the carrier frequency with multiple different phases relative to each other. In some embodiments, the output frequency can be the LO frequency (f _LO ). In some embodiments, RF circuit 206 can include an IQ/polarity converter.

FEM circuitry 208 may include a receive signal path that may include circuitry that operates on RF signals received from one or more antennas 210, amplifies the received signals, and provides the amplified versions of the received signals to RF circuitry 206 for further processing. FEM circuitry 208 may also include a transmit signal path that may include circuitry configured to amplify transmit signals provided by RF circuitry 206 for transmission by one or more of the one or more antennas 210.

In some embodiments, the FEM circuitry 208 may include a TX/RX switch to switch between transmit and receive modes of operation. The FEM circuitry may include a receive signal path and a transmit signal path. The receive signal path of the FEM circuitry may include a low-noise amplifier (LNA) to amplify a received RF signal and provide the amplified received RF signal as an output (e.g., to the RF circuitry 206). The transmit signal path of the FEM circuitry 208 may include a power amplifier (PA) to amplify an input RF signal (e.g., provided by the RF circuitry 206), and one or more filters to generate an RF signal for subsequent transmission (e.g., by one or more of the one or more antennas 210).

In some embodiments, the UE 200 may include additional elements, such as memory/storage devices, displays, cameras, sensors, and/or input/output (I/O) interfaces, which will be described in more detail below. In some embodiments, the UE 200 described herein may be part of a portable wireless communication device, such as a personal digital assistant (PDA), a laptop or portable computer with wireless communication capabilities, a web tablet, a wireless phone, a smartphone, a wireless headset, a pager, an instant messaging device, a digital camera, an access point, a television, a medical device (e.g., a heart rate monitor, a blood pressure monitor, etc.), or other devices that can wirelessly receive and/or send information. In some embodiments, the UE 200 may include one or more user interfaces designed to allow user interaction with the system, and/or peripheral component interfaces designed to allow interaction with peripheral components of the system. For example, the UE 200 may include a keyboard, a keypad, a touchpad, a display, sensors, a non-volatile memory port, a universal serial bus (USB) port, an audio jack, a power port, one or more antennas, a graphics processor, an application processor, a speaker, a microphone, and other I/O components. The display may be an LCD or LED screen including a touch screen. The sensors may include gyroscopic sensors, accelerometers, proximity sensors, ambient light sensors, and positioning units. The positioning units may communicate with components of a positioning network, such as global positioning system (GPS) satellites.

Antenna 210 may include one or more directional or omnidirectional antennas, including, for example, dipole antennas, monopole antennas, patch antennas, loop antennas, microstrip antennas, or other types of antennas suitable for transmitting RF signals. In some multiple-input multiple-output (MIMO) embodiments, antennas 210 may be effectively separated to exploit spatial diversity and potentially different channel characteristics.

Although UE 200 is illustrated as having several separate functional elements, one or more of these functional elements may be combined and may be implemented using a combination of software-configured elements (e.g., a processing element including a digital signal processor (DSP) and/or other hardware elements). For example, some elements may include one or more microprocessors, DSPs, field programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), radio frequency integrated circuits (RFICs), and combinations of various hardware and logic circuits for performing at least the functions described herein. In some embodiments, a functional element may refer to one or more processes operating on one or more processing elements.

Embodiments may be implemented in one or a combination of hardware, firmware, and software. Embodiments may also be implemented as instructions stored on a computer-readable storage device, which may be read and executed by at least one processor to implement the operations described herein. A computer-readable storage device may include any non-transient mechanism for storing information in a machine (e.g., computer) readable form. For example, a computer-readable storage device may include a read-only memory (ROM), a random access memory (RAM), a magnetic disk storage medium, an optical storage medium, a flash memory device, and other storage devices and media. Some embodiments may include one or more processors and may be configured with instructions stored on a computer-readable storage device.

As described above, while GPS/GNSS is a common method for obtaining the UE's location, in some cases, such as when satellite signals are weak (e.g., indoors), GPS/GNSS may not be able to provide location information. In these cases, other radio access technologies can be used to achieve location determination. These technologies can use signals with higher received power than GNSS signals and may therefore be more suitable for use in situations where the only available GNSS signal is weak (thus, the UE's location may only be obtained after a very long time or not at all), or where a more accurate location is required.

Generally, to obtain UE location using radio access technology, MME 122 may receive a request for location services associated with a specific target UE 102 from another entity, or may initiate location services on behalf of the specific target UE 102. The other entity may be UE 102, eNB 104, or E-SMLC 134. MME 122 may initiate location determination, for example, when an E911 call is placed from UE 102. MME 122 may send a location service request to E-SMLC 134. In response, E-SMLC 134 may send assistance data to UE 102 to enable UE-assisted positioning. E-SMLC 134 may receive corresponding measurement data from UE 102 or an eNB 104 serving UE 102, determine a position estimate for UE 102, and return the position estimate and/or an indication of the assistance data transmitted to UE 102 to MME 122. If location services are requested rather than initiated by MME 122, MME 122 may return location service results to the requesting entity and other network entities that may need the UE's location.

Various UE-assisted techniques may be used for UE position determination, including Assisted Global Navigation Satellite System (A-GNSS), Observed Time Difference of Arrival (OTDOA), and Enhanced Cell ID (ECID). Generally, specific resource elements may be used to transmit reference signals (also known as pilot signals), which are known to both the transmitter and receiver and used in UE-assisted techniques. These techniques may use various control signals, such as a Common Reference Signal (CRS) or synchronization/pilot signals (e.g., a Primary Synchronization Signal (PSS) or a Secondary Synchronization Signal (SSS)), that occupy different resource elements. For example, a PRS may use different resource elements than those allocated to a Physical Broadcast Channel (PBC), PSS, SSS, non-zero power Channel State Information (CSI)-RS, or CRS transmitted by the eNB 104 (which may be present in all subframes). The PSS and SSS may be used by the UE for cell search and acquisition. The PSS and SSS may be transmitted by the eNB 104 in downlink subframes at the center 1.08 MHz of the system bandwidth for each cell supported by the eNB 104. In active cells, the PSS and SSS may be sent in symbol periods 6 and 5 in subframes 0 and 5, respectively, of each frame. Specifically, the PSS may be sent in the first subframe for an LTE Type 1 frame structure and in the second subframe for an LTE Type 2 frame structure. The SSS may be sent in the first subframe regardless of the frame structure.

When determining OTDOA, location server 130 or eNB 104 may send OTDOA reference cell information to UE 102. The OTDOA reference cell information may include a physical cell identifier (physCellId), antenna port configuration (antennaPortConfig), cyclic prefix length (cpLength), and PRS information (prsInfo). phyCellId may include the physical cell ID of the reference cell. antennaPortConfig may indicate whether the reference cell uses one, two, or four antenna ports for cell-specific reference signals. cpLength may indicate the length of the cyclic prefix of the PRS of the reference cell. psrInfo may indicate information about the PRS configuration of the reference cell, including a PRS configuration index (prs-ConfigurationIndex), a PRS bandwidth (prs-Bandwidth), the number of downlink frames (numDL-Frames) (hereinafter referred to as duration), and PRS muting information (prs-MutingInfo). The PRS bandwidth may be 6, 15, 35, 50, 75, or 100 resource blocks. Muting parameters may indicate which PRS transmissions to mask (eg, to allow the UE to detect weaker signals from neighboring cells).

UE-assisted position determination is performed using a PRS, which can be sent to UE 102 on antenna port 6 of eNB 104. The PRS can be sent from eNB 104 in a predetermined number of consecutive subframes (e.g., 1-5 subframes). The number of subframes used to send the PRS can be configured by eNB 104. The PRS bandwidth (e.g., the number of RBs) and the PRS periodicity (e.g., the number of subframes between PRS occasions) can also be configured by eNB 104. Within a subframe containing the PRS, the PRS can be sent on more subcarriers and more OFDM symbols than the conventional cell-specific reference signal (CSI-RS) sent by eNB 104. A pseudorandom sequence can be sent with the PRS. The pseudorandom sequence can be a function of factors such as the PCI (physical layer cell identity), the number of slots, the number of OFDM symbols, and the value of the cyclic prefix. UE 102 can detect PRSs from different neighboring eNBs 104, perform measurements based on each PRS, and send the measurements to eNB 104. Examples of such measurements include observed time difference of arrival (OTDOA) measurements, such as reference signal time difference (RSTD). RSTD is the relative time difference between a reference eNB and a neighboring eNB. eNB 104 can process the OTDOA measurements from UE 102 to estimate the UE's position.

UE 102 may be provided with the aforementioned PRS parameters, which may enable UE 102 to process the PRS via higher layer signaling. Specifically, this information may include the carrier index or frequency band on which the PRS is transmitted, the bandwidth of the PRS, the duration (the number of consecutive subframes used for PRS transmission), the transmission period, the subframe offset, and the muting sequence. UE 102 may then report the estimated time offset based on the estimated measurement quality to eNB 104, and eNB 104 may report this information to E-SMLC 134. E-SMLC 134 may estimate the location of UE 102 using the time difference estimate measured by UE 102, the location of the cell (which may be fixed and known), and the transmission time offset. UE 102 may, for example, report the estimated time offset to SLP 132.

Figures 3A-D illustrate downlink channel resource blocks containing PRSs according to some embodiments. Figures 3A-D each illustrate a downlink channel resource block 300 in which a PRS 314 may be transmitted in a downlink channel. Downlink channel resource block 300 may be transmitted by one of eNBs 104. PRS 314 may be mapped to antenna port 6. PRS 314 may be transmitted on one or two PBCH antenna ports, as shown in downlink channel resource blocks 300 and 340 of Figures 3A and 3C , or on four PBCH antenna ports, as shown in downlink channel resource blocks 320 and 360 of Figures 3B and 3D .

3A-D , the subframe 302 includes two time slots 304a, 304b (time slot 0/even time slot 304a and time slot 1/odd time slot 304b). The downlink channel resource blocks 300, 320, 340, 360 in each of FIG3A-D may include multiple resource elements 312. Each resource element 312 may correspond to an OFDM symbol 310 and a subcarrier frequency 306.

In a subframe using a normal cyclic prefix, as shown in Figures 3A and 3B , the resource elements in downlink channel resource blocks 300 and 320 span fourteen OFDM symbols (l=0 to l=6) and twelve frequency subcarriers. In a subframe using an extended cyclic prefix, as shown in Figures 3C and 3D , the resource elements in downlink channel resource blocks 340 and 360 span twelve OFDM symbols (l=0 to l=5) and twelve frequency subcarriers. PRS 314 may be transmitted in one or more resource elements 312 of downlink channel resource blocks 300, 320, 340, 360, labeled _R6 in Figures 3A-D .

As described above, the parameters defining the PRS 314 may be configurable and may be provided in prsInfo. These parameters may include a configuration index (prs-ConfigurationIndex) _IPRS , which has a value of 0-2399 and is mapped to PRS period ( _TPRS ) and PRS offset ( _ΔPRS ) parameters. _TPRS is the PRS period (one PRS subframe every 160, 320, 640, or 1280 subframes) and _ΔPRS is the subframe offset (which may be _IPRS , _IPRS -160, _IPRS -480, or _IPRS -1120, depending on the _IPRS configuration index, and thus ranges from 0 to 1120). The PRS 314 parameters may also include a duration, _NPRS , which may be the number of consecutive downlink subframes with PRS that define the measurement period (e.g., 1, 2, 4, or 6). Table 1 lists the cell-specific subframe configuration period T _PRS and cell-specific subframe offset Δ _PRS for sending positioning reference signals. PRS can be sent only in the configured N _prs consecutive downlink subframes instead of in special subframes. For the first subframe in the N _prs downlink subframes, the PRS instance can satisfy the following equation:

Table 1 Positioning parameter signal subframe configuration

However, similar to GPS location determination, in some cases, determining UE location using PRS may not be sufficient to provide the required level of location accuracy, including vertical positioning. To improve location accuracy, in some embodiments, multiple PRS configurations and/or multiple antenna ports may be configured to allow UE 102 to receive a greater amount of PRS energy. To enable vertical domain positioning, in some embodiments, dedicated antenna ports (APs) may be defined. These features can be used by UEs implementing LTE Release 13 (or later), but may not be backwards compatible with UEs implementing earlier LTE releases, as these UEs may not be able to interpret and utilize the adjusted configurations.

To improve location accuracy, in some embodiments, a new PRS pattern may be used. The new PRS pattern may be generated by the eNB 104 copying the PRS resource elements shown in Figures 3A-3D from the first subframe to the second subframe and transmitting a repeated set of PRS subframes. This may provide more reference signal energy to the UE 102, thereby improving measurement performance. Whether to use the new PRS pattern may be determined by the eNB or location server via SIB signaling. For example, a single bit may be used to indicate whether repeated PRS subframes are to be transmitted by the eNB 104. In one embodiment, this bit may be 0 to indicate that no additional PRS subframes are to be transmitted, which corresponds to the legacy PRS transmission case, and may be 1 to indicate that repeated PRS subframes are to be transmitted.

In embodiments where the second (repeated) subframe(s) are consecutive to the first subframe(s), the number of PRS subframes is effectively doubled. For example, when initially four subframes are configured for PRS (i.e., the number of consecutive subframes in a standard configuration is four), four consecutive subframes containing PRS may be repeated after the last initial subframe containing PRS, ultimately providing eight consecutive subframes for PRS. In other embodiments, the eNB may consider subframes carrying both the PSS and SSS. For example, for a TDD frame structure or for an FDD/TDD/HD-FDD frame structure, the second subframe may be the next available downlink subframe after the first subframe to avoid PRS mapping in subframes carrying the PSS/SSS (subframes 0 and 5). In a TDD frame structure, the next available downlink subframe may be separated from the last PRS subframe by one or more (uplink) subframes.

In some embodiments, the antenna port used to transmit the additional PRS pattern can be the same as the existing port used to transmit the initial pattern (i.e., antenna port 6). In other embodiments, the antenna port can be different from the existing antenna port (i.e., antenna port X, where X is an integer value). In some embodiments, the PRS mapping pattern on resource elements between different subframes can be the same to reduce implementation complexity. In some embodiments, the PRS mapping pattern on resource elements between different subframes can be different to provide additional randomness to combat interference.

In some embodiments, the repetition factor may be greater than 2. In some embodiments, the repetition factor n may be an integer multiple. That is, rather than being simply duplicated (or not duplicated), the PRS subframe may be repeated n times. In one example, if n=3 and the initial PRS subframe includes two consecutive PRS subframes, then six additional PRS subframes (which may be consecutive, for example if there are no intervening PSS or SSS signals to be transmitted) may be transmitted so that a total of eight PRS subframes may be transmitted between consecutive initial PRS subframe occasions. The bit used to indicate the presence of repeated PRS subframes may also be used to indicate a specific pattern, such as the presence of discontinuous PRS subframes that duplicate consecutive PRS subframes. Discontinuous PRS repeated subframes may be separated by a predetermined number of subframes, as long as they are within the configured PRS period. The number of repetitions and the repetition pattern may be indicated by other bits in the control information. In some embodiments, some or all of the repeated PRS subframes may precede the initial PRS subframe.

Instead of or in addition to repeating PRS subframes, PRS subframes can be sent more frequently. That is, the PRS period can be configured to be shorter than the legacy Release 13 minimum of 160 ms (as shown in Table 1). Examples of new periods can be 40 ms or 80 ms, and gap patterns can be considered to provide measurement gaps for UEs where no uplink or downlink data communication is scheduled, enabling the UE to perform measurements in different frequency bands and/or with different radio access technologies. Gap pattern ID 0, with a length of 6 ms and a repetition rate of 40 ms, may only be used for inter-frequency RSTD measurements.

As described above, the new PRS periodicity may be an integer multiple of the Release 13 periodicity. Thus, one or more additional bits may be used to indicate the increased periodicity factor. For example, a bit may be 0 to indicate that the additional legacy PRS periodicity is not in use, and may be 1 to indicate that an additional (repeated) PRS subframe is to be transmitted. Similarly, multiple bits may be used to indicate the factor for the increased periodicity.

Instead of adjusting the repetition and period of the PRS subframe, or in addition to adjusting the repetition and period of the PRS subframe, one or more other reference signal (RS) configurations for the cell can be configured and sent to the UE 102 (e.g., in prs-ConfigurationIndex) to improve RS density. The RS can be any type of RS and can be used for location measurement, such as PRS, CRS, or CSI-RS. Note that the above discussion is based on PRS because PRS can provide the best link budget and thus improve the best results. In some embodiments, multiple PRS-Info configurations can be sent to the UE 102. In some embodiments, one or more parameters in the PRS configuration (PRS-Info) can be configured.

When multiple PRS configurations are transmitted to UE 102, different PRSs in different configurations may be quasi-colocated. If the large-scale channel properties of the channel over which symbols on one antenna port are transmitted can be inferred from the channel over which symbols on another antenna port are transmitted, then the two antenna ports (and thus the PRS transmissions from those ports) may be quasi-colocated. Large-scale channel properties may include delay spread, Doppler spread, Doppler shift, average gain, average delay, received power per port, received timing, and/or frequency offset. In some embodiments, the location server may configure information indicating whether PRSs in different configurations are quasi-colocated for the UE. Such quasi-colocated information may be exchanged between the eNB and the eSMLC. Quasi-colocation may be ensured to utilize multiple PRS instances resulting from multiple PRS configurations. Alternatively, the location server may simply configure the UE to use quasi-colocated PRS instances and non-quasi-colocated PRS instances.

Using quasi-colocated antenna ports allows the UE 102 to coherently or non-coherently accumulate PRSs from different configurations. Coherent accumulation can be used when PRSs are transmitted from the same antenna port with the same precoding scheme and experience the same fading conditions. The antenna ports for PRSs in different PRS configurations can be the same or different. When using the same antenna port, the UE 102 can perform coherent accumulation to improve RSTD measurement performance when PRS subframes from different configurations are close enough in the time domain.

FIG4 illustrates an ASN.1 code for configuring multiple PRS configurations according to some embodiments. The ASN.1 code illustrates multiple PRS configurations in a cell. As described above, prsInfo 410 may include the following parameters: prs-Bandwidth 412, prs-ConfigurationIndex 414, numDL-Frames 418, and prs-MutingInfo 422. In addition, prsInfo 410 may include a new parameter: enhanced-prs-ConfigurationIndexList 416. prs-ConfigurationIndexList 416 may be defined using ASN.1 code definition 422. prs-ConfigurationIndexList 416 may be defined using the notation SEQUENCE(SIZE(1..X))OFprs-ConfigurationIndex, where X may be an integer value (so X different prs-ConfigurationIndex values may be used).

In some embodiments, instead of providing multiple PRS configurations, each with its own independent I_PRS with independent subframe offset and periodicity, a limited number of parameters may be provided. For example, in some embodiments, only different subframe offsets may be provided for signaling optimization. In some embodiments, the different subframe offsets may be associated with the subframes of an existing prs-ConfigurationIndex. Thus, repeated PRS subframes may have the same period as the initial PRS subframe and may only have different offsets. For example, the initial PRS subframe may have _IPRS = 100, TPRS = 160 ms, and _ΔPRS = 100, and the repeated PRS subframe may have _IPRS = 101, TPRS = 160 ms, and _ΔPRS = 101.

Turning to vertical positioning, FIG5 illustrates UE position determination in the horizontal and vertical domains according to some embodiments. During OTDOA positioning, the eNB 504 and/or location server 130 may typically utilize at least two pieces of information to determine the UE position: the distance d 514 between the UE 502 and the antenna port of the eNB 504, and the height h 512 of the antenna port of the eNB 504. The distance d 514 may be derived by the location server 130 (e.g., the e-SMLC 134) based on the measured RSTD in the LTE Positioning Protocol (LPP) or LTE Positioning Protocol A (LPPa). The height h 512 may be fixed and non-variable and may be sent to the location server 130. The location server 130 can obtain the horizontal distance d'516 between the UE 502 and the eNB 504 based on the distance d 514 and the height h 512. Thus, the UE position can be calculated using the various RSTD measurement results (in practice, the relative distance difference obtained from the arrival time difference can be used for positioning, but for convenience, the relative distance difference is described as the absolute distance in this document).

When performing this calculation, the UE altitude can generally be assumed to be on the ground, or the calculation can be ignored. However, in some embodiments, rather than assuming that UE 502 is on the ground, location server 130 can utilize another piece of information θ (Zenith Angle of Arrival (ZoA)) determined by UE 502 to determine the UE altitude. ZoA can be used to represent the angle of arrival in the vertical domain. Similar to the angle of arrival (AoA), which is used to represent the angle of arrival in the horizontal domain, ZoA can be measured based on uplink transmissions from UE 502 and the known configuration of the eNB antenna array. The received UE signals between consecutive antenna elements can be phase offset, and the degree of phase offset can depend on the ZoA, antenna element spacing, and carrier frequency. By measuring the phase offset and utilizing known eNodeB characteristics, the ZoA can be determined. Typical uplink signals used in this measurement are the Sounding Reference Signal (SRS) or the Demodulation Reference Signal (DM-RS), which can also be used to determine uplink channel quality or timing advance.

The horizontal domain UE position can be calculated based on d' 516 from different cells using an OTDOA procedure, where, as described above, d 514 is the distance between UE 502 and the antenna port of eNB 504. The vertical domain UE position h' 518 can be calculated based on the height h 512 and the ZOAθ of the OTDOA signal from eNB 504, where h' = h - cosθ. Measurements from multiple eNBs 504 can be utilized for vertical domain positioning to improve accuracy.

In some embodiments, to obtain θ, UE 502 can determine the ZoA or precoding matrix by measuring downlink signals and/or channels (e.g., control signals in the PDCCH) from eNB 504. Alternatively, the ZoA or precoding matrix can be determined by eNB 504 by measuring uplink signals such as aperiodic SRS or DM-RS, or PRACH transmissions based on the PDCCH order. In this case, antenna ports for the horizontal domain and the vertical domain can be shared. When UE 502 determines the value of θ (or ZoA/precoding matrix index), related parameters can be defined for LPP so that location server 130 can utilize this information. When eNB 504 determines the value of θ, related parameters can be defined for LPPa so that location server 130 can utilize this information.

In some embodiments, multiple RS configurations of the eNB 504 may be utilized for vertical domain positioning of the UE 502. For example, either or both of a PRS configuration (e.g., as described above) and/or a CSI-RS configuration may be utilized. A first RS configuration may be used for horizontal domain positioning, and a second RS configuration may be used for vertical domain positioning. The RS configurations may be the same or different and may depend, for example, on signal strength or other factors. The configurations of the first RS and the second RS may be, for example, {PRS, PRS}, {PRS, CSI-RS}, {CSI-RS, PRS}, {PRS, CRS}, {CRS, CRS}, {CRS, CSI-RS}.

Regardless of which available RS is used, horizontal domain positioning can be calculated using RS transmissions from the first antenna port of the eNB 504. This transmission can use, for example, a standard RS configuration or a modified RS configuration, as described above in conjunction with Figures 3A-D and 4. Figure 6 illustrates vertical UE position determination using multiple reference signal configurations, according to some embodiments. RS transmissions (e.g., CSI-RS or PRS) from the second antenna port of the eNB 604 to the UE 602 can be beamformed and associated with a predetermined structure. For example, four fixed vertical beams 612, 614, 616, and 618 can be transmitted via four different RS configurations (e.g., CSI processes, PRS configurations, CSI-RS configurations, etc.) to enable the UE 102 to determine a preferred beam. Using different RS configurations, each corresponding to a different angle, allows the UE 602 to distinguish between different transmissions and provide angle information to the eNB 604. The UE can measure signals from one or more of the different configurations and determine which configuration is being measured. The measured parameter may be, for example, a signal-to-interference plus noise ratio (SINR), reference signal received power (RSRP) (average power of REs carrying RSs across the entire bandwidth), or received reference signal quality (RSRQ) (indicating the quality of received RSs). The specific configuration with the highest value of the measured parameter (or angle-related parameter) may be reported to the location server 130 via LLP signaling to determine the vertical position of the UE 602.

Different antenna ports or configurations for horizontal and vertical positioning may be quasi-collocated. In this case, the second RS configuration may be used not only to determine the angle but also for RSTD measurements. In this case, the order in which the measurement results for different PRS configurations are reported may be the same as the order in which the PRS configurations are provided by the location server 130, so that the location server 130 can distinguish between the different information when they are received by the eNB 604.

FIG7 illustrates a flowchart for determining a UE's location according to some embodiments. The method illustrated by the flowchart may be performed by the elements shown in FIG1-2 and FIG5-6, including the UE, eNB, and/or location server shown. At operation 702, the eNB may transmit multiple RS configurations to the UE. The RS configurations may be, for example, PRS configurations that indicate to the UE that different PRS patterns are being transmitted by the eNB. PRSs of different PRS configurations may be transmitted using the same or different antenna ports of the eNB. Resource elements in a non-legacy PRS subframe may simply replicate PRS resource elements from a legacy PRS subframe or may not rely on resource elements of a legacy PRS subframe. Non-legacy PRS subframes may be contiguous or non-contiguous with legacy PRS subframes, such that they occur after legacy PRS subframes. The eNB may consider subframes carrying the PSS and SSS and utilize the next available downlink subframe (which may be separate from the previous legacy PRS subframe due to an uplink subframe). Each PRS configuration may have its own independent configuration index with independent subframe offset and periodicity.

In some embodiments, rather than providing a new PRS configuration, the PRS configuration may be adjusted in one or more non-legacy ways. Various parameters in the PRS configuration may be changed to adopt non-legacy values. For example, the period may be extended to allow the PRS to be sent more frequently. Repetitions may take into account an interval pattern.

In addition, the UE may receive one or more other RS configurations from the eNB or other eNBs. The RS configuration may be for PRS, CRS, CSI-RS, SRS, or DM-RS control signals to be measured by the UE for vertical positioning and for determining channel quality. The same or dedicated antenna ports may be defined for the eNB for vertical positioning signal transmission and horizontal positioning signal transmission. Different vertical beams utilizing different RSs (or RSs with different characteristics) may be transmitted by the eNB at different angles.

As described above, the UE may be a legacy UE configured to operate using the LTE pre-Release 13 standard, or a non-legacy UE. The UE may determine whether to use the new PRS pattern at operation 704. The eNB may transmit a PRS configuration including the new PRS pattern via the SIB (regardless of whether the new PRS configuration is added or the legacy PRS configuration is changed).

If the UE is not a legacy UE, the UE can read and understand the PRS configuration. Thus, in addition to the legacy PRS configuration, the non-legacy UE can accept the new PRS configuration or can accept non-legacy values used in the PRS configuration. The non-legacy UE can measure the entire PRS set (including legacy and non-legacy PRS) at operation 706. The non-legacy UE can also obtain and measure RS signals from the eNB. The non-legacy UE can use the RS signals to determine the ZOA or precoding matrix.

If the UE is a legacy UE, in some embodiments, the UE may not be able to read and understand the new, separate non-legacy PRS configuration or the PRS configuration with non-legacy values. In the former case, the legacy UE may ignore the separate non-legacy PRS configuration. In the latter case, the legacy UE may not understand the values provided in the modified legacy PRS configuration and send an error message to the eNB, or may utilize a set of default values provided by the eNB via control signaling. The legacy UE may measure only the legacy PRS at operation 708. The legacy UE may utilize RS signals to determine the ZOA or precoding matrix.

Regardless of whether the UE measures both legacy and non-legacy PRS or only legacy PRS, at operation 710, the UE may report the estimated time offset and the estimated value of the measurement quality to the eNB. The eNB may in turn report the information from the UE to a location server. The location server may use the time difference estimate, the known cell locations, and the measured transmit time offset to estimate the lateral position of the UE relative to the eNB.

The location server may also receive RS measurement results from the UE. Alternatively or additionally, the location server may receive at least one of ZOA and precoding matrix information. The UE may distinguish between different transmissions and provide angle information to the eNB. Specifically, whether appropriate in operation 706 or operation 708, the UE may measure signals of one or more configurations with the best characteristics among the different configurations and determine which configuration is being measured before reporting to the eNB/location server. Using this information and the distance between the UE and the eNB, the location server may also calculate the vertical position of the UE.

FIG8 is a block diagram of a communications device according to some embodiments. The device may be a UE or an eNB, such as UE 102 or eNB 104 shown in FIG1 , which may be configured to track a UE as described herein. Communications device 800 may include physical layer circuitry 802 for transmitting and receiving signals using one or more antennas 801. Communications device 800 may also include medium access control (MAC) layer circuitry 804 for controlling access to a wireless medium. Communications device 800 may also include processing circuitry 806, such as one or more single-core or multi-core processors, and memory 808, arranged to perform the operations described herein. Physical layer circuitry 802, MAC circuitry 804, and processing circuitry 806 may handle various radio control functions that enable communication with one or more radio networks compatible with one or more radio technologies. Radio control functions may include signal modulation, encoding, decoding, radio frequency offset, and the like. For example, similar to the device shown in FIG2 , in some embodiments, communications may be implemented using one or more of a WMAN, a WLAN, and a WPAN. In some embodiments, the communication device 800 can be configured to operate according to the 8GPP standard or other protocols or standards, including WiMax, WiFi, GSM, EDGE, GERAN, UMTS, UTRAN or other 8G, 8G, 4G, 5G, etc. technologies that have been developed or will be developed.

Antenna 801 may include one or more directional or omnidirectional antennas, including, for example, dipole antennas, monopole antennas, patch antennas, loop antennas, microstrip antennas, or other types of antennas suitable for transmitting RF signals. In some MIMO embodiments, antennas 801 may be effectively separated to exploit spatial diversity and potentially different channel characteristics.

Although the communication device 800 is illustrated as having several separate functional elements, one or more of these functional elements can be combined and can be implemented with a combination of elements configured by software, which elements include, for example, the processing elements of a DSP and/or other hardware elements. For example, some elements may include a combination of various hardware and logic circuits for performing at least the functions described herein, one or more microprocessors, DSPs, FPGAs, ASICs, RFICs, and the like. In some embodiments, a functional element may refer to one or more processing operations performed on one or more processing elements. Embodiments may be implemented in one or a combination of hardware, firmware, and software. Embodiments may also be implemented as instructions stored on a computer-readable storage device, which may be read and executed by at least one processor to implement the operations described herein.

FIG9 shows a block diagram of an example machine according to some embodiments. Any one or more of the techniques (e.g., methods) discussed herein can be performed by an example machine 900. In alternative embodiments, machine 900 can operate as a standalone device or can be connected (e.g., networked) to other machines. In a networked deployment, machine 900 can operate as a server machine, a client machine, or both in a server-client network environment. In an example, machine 900 can function as a peer machine in a peer-to-peer (P2P) (or other distributed) network environment. Machine 900 can be a UE, an eNB, an AP, a STA, a personal computer (PC), a tablet PC, a STB, a PDA, a mobile phone, a smartphone, a web appliance, a network router, a switch, or a bridge, or any machine capable of executing instructions (sequential or otherwise) specifying actions to be taken by the machine. Furthermore, while a single machine is shown, the term "machine" should also be construed to include any collection of machines that individually or collectively execute a set (or multiple sets) of instructions to implement any one or more of the methods discussed herein, such as cloud computing, software as a service (SaaS), or other computer cluster configurations.

Examples as described herein may include logic or multiple components, modules or mechanisms, or may be operated on logic or multiple components, modules or mechanisms. A module is a tangible entity (e.g., hardware) that can perform a specified operation and may be configured or arranged in a particular manner. In an example, a circuit may be arranged in a specified manner as a module (e.g., internally or for an external entity such as other circuits). In an example, the entirety or part of one or more computer systems (e.g., stand-alone, client, or server computer systems) or one or more hardware processors may be configured to operate as a module that performs a specified operation by firmware or software. In an example, software may be located on a machine-readable medium. In an example, software causes the hardware to perform a specified operation when the lower hardware of the module is executed.

Accordingly, the term "module" is understood to include a tangible entity, i.e., an entity that is physically constructed, specifically configured (e.g., hardwired), or temporarily (e.g., transiently) configured to operate in a specified manner or to perform part or all of any operations described herein. Considering an example in which a module is temporarily configured, each module need not be instantiated at any one time. For example, where a module comprises a general-purpose hardware processor configured using software, the general-purpose hardware processor can be configured as corresponding different modules at different times. The software can configure the hardware processor accordingly, for example, to construct a particular module at one time and to construct a different module at a different time.

The machine (e.g., a computer system) 900 may include a hardware processor 902 (e.g., a central processing unit (CPU), a graphics processing unit (GPU), a hardware processor core, or any combination thereof), a main memory 904, and a static memory 906, some or all of which may communicate with each other via an interconnection (e.g., a bus) 908. The machine 900 may also include a display unit 910, an alphanumeric input device 912 (e.g., a keyboard), and a user interface (UI) navigation device 914 (e.g., a mouse). In an example, the display unit 910, the input device 912, and the UI navigation device 914 may be a touch screen display. The machine 900 may also include a storage device (e.g., a drive unit) 916, a signal generating device 918 (e.g., a speaker), a network interface device 920, and one or more sensors 921, such as a global positioning system (GPS) sensor, a compass, an accelerometer, or other sensors. The machine 900 may include an output controller 928, such as a serial (e.g., Universal Serial Bus (USB)), parallel, or other wired or wireless (e.g., infrared (IR), near field communication (NFC), etc.) connection to communicate with or control one or more peripheral devices (e.g., printer, card reader, etc.).

The storage device 916 may include a machine-readable medium 922 having stored thereon one or more data structures or instructions 924 (e.g., software) that embody or are utilized by any one or more of the techniques or functionality described herein. The instructions 924 may also reside, completely or at least partially, within the main memory 904, within the static storage 906, or within the hardware processor 902 during execution thereof by the machine 900. In an example, one or any combination of the hardware processor 902, the main memory 904, the static storage 906, or the storage device 916 may constitute a machine-readable medium.

Although machine-readable medium 922 is shown as a single medium, the term “machine-readable medium” may include a single medium or multiple media (eg, a centralized or distributed database, and/or associated caches and servers) configured to store one or more instructions 924 .

The term "machine-readable medium" may include any medium capable of storing, encoding, or carrying instructions, or capable of storing, encoding, or carrying data structures used by or associated with these instructions, the instructions being executed by the machine 900 and causing the machine 900 to perform any one or more of the techniques disclosed herein. Non-limiting examples of machine-readable media may include solid-state memory, and optical and magnetic media. Specific examples of machine-readable media may include: non-volatile memory, such as semiconductor memory devices (e.g., electrically programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM)) and flash memory devices; magnetic disks, such as internal hard disks and removable magnetic disks; magneto-optical disks; random access memory (RAM); and CD-ROM and DVD-ROM disks. In some examples, the machine-readable medium may include non-transitory machine-readable media. In some examples, the machine-readable medium may include machine-readable media that is not a transient propagation signal.

Instructions 924 may also be sent or received over a communication network 926 using a transmission medium via a network interface device 920 that utilizes any of a number of transport protocols (e.g., frame relay, Internet Protocol (IP), transmission control protocol (TCP), user datagram protocol (UDP), hypertext transfer protocol (HTTP), etc.). Example communication networks may include a local area network (LAN), a wide area network (WAN), a packet data network (e.g., the Internet), a mobile phone network (e.g., a cellular network), a plain old telephone (POTS) network, and a wireless data network (e.g., the so-called Institute of Electrical and Electronics Engineers (IEEE) 802.11 series of standards, the so-called IEEE 802.16 series of standards), the IEEE 802.15.4 series of standards, the Long Term Evolution (LTE) series of standards, the Universal Mobile Telecommunications System (UMTS) series of standards, peer-to-peer (P2P) networks, etc. In an example, the network interface device 920 may include one or more physical jacks (e.g., Ethernet, coaxial, or telephone jacks) or one or more antennas to connect to the communication network 926. In an example, the network interface device 920 may include multiple antennas to facilitate wireless communication using at least one of single-input multiple-output (SIMO), multiple-input multiple-output (MIMO), or multiple-input single-output (MISO) techniques. In some examples, the network interface device 920 may utilize multi-user MIMO technology for wireless communication. The term "transmission medium" shall be deemed to include any intangible medium capable of storing, encoding, or carrying instructions for execution by the machine 900, including digital or analog communication signals or other intangible media to facilitate communication of such instructions.

Example 1 is an apparatus of a user equipment (UE), comprising: a transceiver arranged to communicate with an enhanced NodeB (eNB); and processing circuitry arranged to: configure the transceiver to receive multiple reference signals (RSs), the RSs comprising a first PRS pattern received in a first set of positioning reference signal (PRS) subframes and a second PRS pattern received in a second set of PRS subframes, wherein the second set of PRS subframes is received by the transceiver prior to the following first set of PRS subframes; measure PRS resource elements (REs) in the first and second PRS patterns, each PRS RE comprising a PRS; and configure the transceiver to transmit measurement results of the PRS in each of the first and second PRS patterns to allow determination of the horizontal and vertical positioning of the UE based on the measurement results.

In Example 2, the subject matter of Example 1 can optionally include the processing circuit being further arranged to configure the transceiver to receive a prsInfo control signal including first and second PRS configurations, the first and second PRS configurations indicating first and second PRS patterns, respectively.

In Example 3, the subject matter of Example 2 optionally includes the first and second PRS configurations comprising a legacy PRS configuration and a non-legacy PRS configuration, the legacy PRS configuration indicating a PRS that can be received by legacy and non-legacy UEs, the non-legacy PRS configuration indicating a PRS that can be received by the non-legacy UE, the legacy UE being configured to communicate using a standard prior to Release 13 of the 3rd Generation Partnership Project Long Term Evolution (3GPP LTE) standard.

In Example 4, the subject matter of any one or more of Examples 2-3 may optionally include each of the first and second PRS configurations including parameters independent of parameters in the other of the first and second PRS configurations, the parameters including a configuration index having a subframe offset and a period.

In Example 5, the subject matter of any one or more of Examples 1-4 may optionally include PRS REs in a non-legacy PRS subframe of the non-legacy PRS pattern repeating PRS REs in a legacy PRS subframe of the legacy PRS pattern.

In Example 6, the subject matter of any one or more of Examples 1-5 may optionally include that the first and second PRS patterns are quasi-colocated.

In Example 7, the subject matter of any one or more of Examples 1-6 optionally includes that the first and second groups of PRS subframes are consecutive downlink subframes excluding one or more subframes, wherein each of the excluded one or more subframes includes at least one of a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) and is placed after the first group of PRS subframes and before the second group of PRS subframes.

In Example 8, the subject matter of any one or more of Examples 1-7 optionally includes, wherein the processing circuit is further arranged to: configure the transceiver to receive a prsInfo control signal including a PRS configuration, the PRS configuration indicating PRS subframes having a period of less than 160 ms that form the first and second PRS patterns.

In Example 9, the subject matter of any one or more of Examples 1-8 may optionally include the PRSs of the first and second PRS patterns being received from different antenna ports of the eNB.

In Example 10, the subject matter of any one or more of Examples 1-9 optionally includes the RS further comprising a vertically positioned RS received from a different antenna port than the horizontally positioned RS.

In Example 11, the subject matter of Example 10 optionally includes the processing circuit being further arranged to measure a reference signal time difference (RSTD) using at least one RS among the RSs, and determine at least one of a zone of arrival (ZOA) and a precoding matrix of at least one RS among the RSs, at least one of the ZOA and the precoding matrix and the RSTD providing information to determine a vertical position of the UE.

In Example 12, the subject matter of Example 11 optionally includes the laterally positioned RS and the vertically positioned RS including different RS configurations, at least one of the different antenna ports and configurations being quasi-co-located, and the processing circuit is further arranged to configure the transceiver to send measurement results for the laterally positioned RS and the vertically positioned RS in the same order as the RS configurations are received by the transceiver.

In Example 13, the subject matter of any one or more of Examples 1-12 optionally includes the processing circuit being further arranged to configure the transceiver to receive RS at different angles, the RS received at different angles including different RS configurations; measure the RS; determine a specific RS configuration among the RS configurations of the RS that has the highest value of the measured parameter; and configure the transceiver to report the specific RS configuration to the location server.

In Example 14, the subject matter of any one or more of Examples 1-13 may optionally further include an antenna configured to transmit and receive communications between the transceiver and at least one of the source and target eNBs.

Example 15 is an apparatus of an enhanced NodeB (eNB), comprising: a transceiver arranged to communicate with a user equipment (UE); and a processing circuit arranged to configure the transceiver to send a prsInfo control signal including at least one PRS configuration to the UE; configure the transceiver to send a plurality of reference signals (RSs) to the UE after sending the prsInfo control signal, the RSs including a first PRS pattern in a first group of positioning reference signal (PRS) subframes and a second PRS pattern in a second group of PRS subframes, wherein the second group of PRS subframes is sent before the subsequent first group of PRS subframes; configure the transceiver to receive measurement results of the PRS in each of the first and second PRS patterns from the UE; and determine the horizontal and vertical positioning of the UE based on the measurement results.

In Example 16, the subject matter of Example 15 optionally includes the prsInfo control signal comprising first and second PRS configurations, the first and second PRS configurations indicating first and second PRS patterns, respectively, and at least one of the following configurations being present: the first and second PRS configurations comprising a legacy PRS configuration and a non-legacy PRS configuration, the legacy PRS configuration indicating a PRS that can be received by legacy and non-legacy UEs, the non-legacy PRS configuration indicating a PRS that can be received by non-legacy UEs, the legacy UEs being configured to communicate using a standard prior to Release 13 of the 3rd Generation Partnership Project Long Term Evolution (3GPP LTE) standard; and each of the first and second PRS configurations comprising parameters independent of parameters in the other of the first and second PRS configurations, the parameters comprising a configuration index having a subframe offset and a periodicity.

In Example 17, the subject matter of any one or more of Examples 15-16 may optionally include PRS resource elements (REs) in a non-legacy PRS subframe of the non-legacy PRS pattern repeating PRS REs in a legacy PRS subframe of the legacy PRS pattern.

In Example 18, the subject matter of any one or more of Examples 15-17 optionally includes, wherein the processing circuit is further arranged to determine whether to send an intermediate subframe between the first group of PRS subframes and the second group of PRS subframes, wherein the intermediate subframe includes at least one of a primary synchronization signal (PSS) and a secondary synchronization signal (SSS); configure the transceiver to send the first and second groups of PRS subframes in non-contiguous downlink subframes in response to determining that the intermediate subframe is to be sent; and configure the transceiver to send the first and second groups of PRS subframes in contiguous downlink subframes in response to determining that the intermediate subframe is not to be sent.

In Example 19, the subject matter of any one or more of Examples 15-18 may optionally include the PRSs of the first and second PRS patterns being transmitted from different antenna ports of the eNB.

In Example 20, the subject matter of any one or more of Examples 15-19 optionally includes the RS further comprising a vertically positioned RS transmitted from a different antenna port than the horizontally positioned RS.

In Example 21, the subject matter of any one or more of Examples 15-20 optionally includes the processing circuit being further arranged to configure the transceiver to receive measured values related to a peak of arrival (ZOA) of at least one of the RSs and at least one of the precoding matrices from the UE; and configure the transceiver to send information related to the measured values for determining the vertical position of the UE to an evolved serving mobile location center (E-SMLC) via a Long Term Evolution (LTE) Positioning Protocol Annex (LPPa).

In Example 22, the subject matter of Example 21 optionally includes that the RS further includes a vertically positioned RS and a horizontally positioned RS having different RS configurations, and the processing circuit is further arranged to configure the transceiver to receive measurement results for the horizontally positioned RS and the vertically positioned RS from the UE in the same order as the RS configurations are sent by the transceiver.

In Example 23, the subject matter of any one or more of Examples 15-22 may optionally include the processing circuit being further arranged to configure the transceiver to transmit the RS at different angles, the RS transmitted at different angles comprising different RS configurations.

Example 24 is a non-transitory computer-readable storage medium storing instructions, the instructions being executed by one or more processors of a user equipment (UE) to configure the UE to communicate with an enhanced NodeB (eNB), such that the one or more processors configure the UE to receive a prsInfo control signal including at least one PRS configuration and subsequent multiple reference signals (RSs), the RSs including a first PRS pattern received in a first group of positioning reference signal (PRS) subframes and a second PRS pattern received in a second group of PRS subframes, the second group of PRS subframes being received by the transceiver before the subsequent first group of PRS subframes, the RSs including vertically positioned RSs and horizontally positioned RSs; measure PRS resource elements (REs) in the first and second PRS patterns, each PRS resource element including a PRS; and send measurement results of the PRSs in each of the first and second PRS patterns.

In Example 25, the subject matter of Example 24 may optionally include that the prsInfo control signal includes first and second PRS configurations, the first and second PRS configurations indicating first and second PRS patterns, respectively, the first and second PRS configurations including a legacy PRS configuration and a non-legacy PRS configuration, the legacy PRS configuration indicating a PRS that can be received by legacy and non-legacy UEs, the non-legacy PRS configuration indicating a PRS that can be received by the non-legacy UE, the legacy UE being configured to communicate using a standard prior to Release 13 of the 3rd Generation Partnership Project Long Term Evolution (3GPP LTE) standard, and each of the first and second PRS configurations including parameters independent of parameters in another of the first and second PRS configurations, the parameters including a configuration index having a subframe offset and a periodicity.

In Example 26, the subject matter of any one or more of Examples 24-25 optionally includes that the horizontally positioned RS and the vertically positioned RS include different RS configurations, and the one or more processors further configure the UE to measure a reference signal time difference (RSTD) using at least one of the RSs, and determine a zone of arrival (ZOA) and at least one of the precoding matrices of at least one of the RSs, at least one of the ZOA and the precoding matrix and the RSTD providing information to determine a vertical position of the UE.

In Example 27, the subject matter of any one or more of Examples 24-26 optionally includes one or more processors further configuring the UE to receive RS at different angles, the RS received at different angles including different RS configurations; measuring the RS; determining a specific RS configuration among the RS configurations of the RS having the highest value of the measured parameter; and reporting the specific RS configuration to a location server.

Although the embodiments have been described with reference to specific example embodiments, it will be appreciated that various modifications and changes may be made to these embodiments without departing from the broader spirit and scope of the present disclosure. Therefore, the description and drawings are to be regarded as illustrative and not restrictive. The drawings forming part of the description show, by way of illustration and not limitation, specific embodiments in which the subject matter of the present application may be implemented. The illustrated embodiments are described in sufficient detail to enable those skilled in the art to implement the teachings disclosed herein. Other embodiments may be utilized and obtained so that structural and logical substitutions and changes may be made without departing from the scope of the present disclosure. Therefore, this detailed description is not to be regarded as limiting, and the scope of the various embodiments is limited only by the scope of the appended claims and the equivalents of these claims.

These embodiments of the subject matter of the present invention may be referred to herein individually and/or collectively by the term "invention", which term is merely for convenience and is not intended to actively limit the scope of this application to any single invention or inventive concept (in the case where more than one embodiment is actually disclosed). Thus, although specific embodiments have been illustrated and described herein, it should be understood that any arrangement designed to achieve the same purpose can be replaced with the specific embodiments shown. This disclosure is intended to cover any and all adaptations or variations of the various embodiments. Combinations of the above embodiments and other embodiments not specifically described herein will be understood by those skilled in the art after reviewing the above description.

In this document, as is common in patent literature, the words "a" and "an" are used to include one or more, independent of any other instance or use of "at least one" or "one or more." In this document, the word "or" is used to refer to a non-exclusive or, for example, "A or B" includes "A but not B," "B but not A," and "A and B," unless otherwise indicated. In this document, the words "including" and "in which" are used as the plain-English equivalents of the respective terms "comprising" and "wherein." Furthermore, in the appended claims, the words "including" and "comprising" are open-ended, that is, systems, UEs, articles, compositions, formulas, or processes that include elements other than those listed after such words in the claim are still considered to fall within the scope of the claim. Furthermore, in the appended claims, the words "first," "second," and "third" are used merely as labels and are not intended to impose numerical requirements on their objects.

The Abstract of the present disclosure is provided to comply with 37 C.F.R. §1.72(b), requiring an abstract that allows the reader to quickly ascertain the nature of the technical disclosure. The submitted abstract should be understood that it will not be used to interpret or limit the scope and meaning of the claims. Furthermore, in the foregoing detailed description, it may be seen that various features are grouped together in a single embodiment for the purpose of organizing the contents of the present disclosure. This method of disclosure is not to be interpreted as reflecting an intent that the claimed embodiments require more features than are expressly recited in each claim. Rather, as reflected in the appended claims, the inventive subject matter depends upon fewer than all the features of a single disclosed embodiment. Accordingly, the appended claims are incorporated into the detailed description, with each claim standing on its own as a separate embodiment.

Claims (33)

1. An apparatus for a user equipment (UE), comprising: Transceiver, the transceiver being configured to communicate with a base station (BS); and Processing circuit, the processing circuit being arranged as follows: The transceiver is configured to receive a PRS-Info control signal, the PRS-Info control signal including a first Positioning Reference Signal (PRS) configuration index and a second PRS configuration index for the cell of the base station, wherein the first PRS configuration index indicates the period and offset for a first PRS mode, and wherein the second PRS configuration index indicates the period and offset for a second PRS mode. The transceiver is configured to receive multiple reference signals (RS) from the cell, the RS including a first PRS mode received by the transceiver in a first set of PRS subframes and a second PRS mode received by the transceiver in a second set of PRS subframes; Measure the PRS of the first PRS mode and the second PRS mode; and The transceiver is configured to transmit PRS measurements for the first PRS mode and the second PRS mode so that the horizontal and vertical positioning of the UE can be determined based on the measurements. 2. The apparatus according to claim 1, wherein the prs-Info control signal includes a first PRS configuration and a second PRS configuration, the first PRS configuration and the second PRS configuration respectively indicating the first PRS mode and the second PRS mode, and respectively including the first PRS configuration index and the second PRS configuration index. 3. The apparatus according to claim 2, The first PRS configuration and the second PRS configuration include legacy PRS configuration and non-legacy PRS configuration. The legacy PRS configuration indicates a PRS that can be decoded by both legacy and non-legacy UEs, and the non-legacy PRS configuration indicates a PRS that can be decoded by both non-legacy UEs. The legacy UEs were configured to communicate using versions prior to 3GPP LTE (3rd Generation Partnership Project Long Term Evolution) standard version 13. 4. The apparatus of claim 2, wherein each of the first PRS configuration and the second PRS configuration includes parameters independent of the parameters in the other PRS configuration of the first PRS configuration and the second PRS configuration. 5. The apparatus according to claim 1 or 2, wherein the PRS in the non-legacy PRS subframe of the non-legacy PRS mode repeats the PRS in the legacy PRS subframe of the legacy PRS mode. 6. The apparatus according to claim 1 or 2, wherein the first PRS mode and the second PRS mode are quasi-isomorphic. 7. The apparatus of claim 1 or 2, wherein the first group of PRS subframes and the second group of PRS subframes are consecutive downlink subframes excluding one or more subframes, wherein each of the excluded one or more subframes includes at least one of a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) and is placed after the first group of PRS subframes and before the second group of PRS subframes. 8. The apparatus according to claim 1 or 2, wherein the processing circuitry is further arranged as follows: The transceiver is configured to receive a prs-Info control signal including a PRS configuration, wherein the PRS configuration indicates PRS subframes with a period of less than 160 ms that form the first PRS mode and the second PRS mode. 9. The apparatus of claim 1 or 2, wherein the PRS of the first PRS mode and the second PRS mode are received from different antenna ports of the BS. 10. The apparatus of claim 1 or 2, wherein the RS further comprises a vertical positioning RS received from a different antenna port compared to the lateral positioning RS. 11. The apparatus of claim 10, wherein the processing circuit is further arranged as follows: At least one of the RSs is used to measure the reference signal time difference (RSTD), and Determine the ZOA (Zero Oscillation Oscillation) of at least one of the RSs and at least one of the precoding matrices. The ZOA and at least one of the precoding matrices and the RSTD provide information sufficient to determine the vertical position of the UE. 12. The apparatus according to claim 11, The lateral positioning RS and the vertical positioning RS include different RS configurations. At least one of the different antenna ports and configurations is quasi-co-located, and The processing circuitry is further configured to transmit measurement results for the lateral positioning RS and the vertical positioning RS in the same order as the RS configuration is received by the transceiver. 13. The apparatus according to claim 1 or 2, wherein the processing circuitry is further arranged as follows: The transceiver is configured to receive the RS at different angles, and the RS received at different angles includes different RS configurations; Measure the RS; Determine the specific RS configuration that has the highest value of the measured parameter among the RS configurations of the RS; Configure the transceiver to report the specific RS configuration to the location server. 14. An apparatus for a base station (BS), comprising: Transceiver, the transceiver being configured to communicate with a user equipment (UE); and Processing circuit, the processing circuit being arranged as follows: The transceiver is configured to send a prs-Info control signal to the UE. The prs-Info control signal includes a first Positioning Reference Signal (PRS) configuration index and a second PRS configuration index for the cell of the base station. The first PRS configuration index indicates the period and offset for a first PRS mode, and the second PRS configuration index indicates the period and offset for a second PRS mode. The transceiver is configured to send multiple reference signals (RS) corresponding to the cell to the UE after transmitting the PRS-Info control signal. These RSs include a first PRS mode in a first set of PRS subframes and a second PRS mode in a second set of PRS subframes. The transceiver is configured to receive PRS measurements from the UE in each of the first and second PRS modes so that the UE's horizontal and vertical positioning can be determined based on the measurements. 15. The apparatus according to claim 14, The prs-Info control signal includes a first PRS configuration and a second PRS configuration. The first PRS configuration and the second PRS configuration respectively indicate the first PRS mode and the second PRS mode, and respectively include the first PRS configuration index and the second PRS configuration index. At least one of the following is true: The first PRS configuration and the second PRS configuration include legacy PRS configuration and non-legacy PRS configuration. The legacy PRS configuration indicates PRS that can be received by both legacy and non-legacy UEs, and the non-legacy PRS configuration indicates PRS that can be received by non-legacy UEs. The legacy UE is configured to communicate using standards prior to version 13 of the 3GPP LTE standard. Each of the first PRS configuration and the second PRS configuration includes parameters that are independent of the parameters in the other PRS configuration of the first PRS configuration and the second PRS configuration. 16. The apparatus of claim 14 or 15, wherein the PRS resource element (RE) in the non-legacy PRS subframe of the non-legacy PRS mode repeats the PRS RE in the legacy PRS subframe of the legacy PRS mode. 17. The apparatus of claim 14 or 15, wherein the processing circuitry is further arranged as follows: Determine whether to transmit an intermediate subframe between the first group of PRS subframes and the second group of PRS subframes, the intermediate subframe including at least one of a primary synchronization signal (PSS) and a secondary synchronization signal (SSS); The transceiver is configured to transmit the first set of PRS subframes and the second set of PRS subframes in non-contiguous downlink subframes in response to determining that the intermediate subframes should be transmitted; and The transceiver is configured to transmit the first set of PRS subframes and the second set of PRS subframes in consecutive downlink subframes in response to determining that there are no intermediate subframes to transmit. 18. The apparatus of claim 14 or 15, wherein the PRS of the first PRS mode and the second PRS mode are transmitted from different antenna ports of the BS. 19. The apparatus of claim 14 or 15, wherein the RS further comprises a vertical positioning RS transmitted from a different antenna port compared to the lateral positioning RS. 20. The apparatus of claim 14 or 15, wherein the processing circuitry is further arranged as follows: The transceiver is configured to receive from the UE a measured value associated with at least one of the RSs' peak arrival (ZOA) and at least one of the precoding matrices; and The transceiver is configured to send information related to the measured value for determining the vertical position of the UE to the evolved Serving Mobile Location Centre (E-SMLC) via the Long Term Evolution (LTE) Positioning Protocol Appendix (LPPa). 21. The apparatus according to claim 20, The RS further includes a vertical positioning RS and a lateral positioning RS, the vertical positioning RS and the lateral positioning RS including different RS configurations, and The processing circuitry is further configured to receive measurement results for the lateral positioning RS and the vertical positioning RS from the UE in the same order as the RS configuration is transmitted by the transceiver. 22. The apparatus of claim 14 or 15, wherein the processing circuitry is further arranged as follows: The transceiver is configured to transmit the RS at different angles, and the RS transmitted at different angles includes different RS configurations. 23. A non-transitory computer-readable storage medium storing instructions, wherein the instructions, when executed by one or more processors of a user equipment (UE), configure the UE to: Receive a PRS-Info control signal, wherein the PRS-Info control information includes a first Positioning Reference Signal (PRS) configuration index and a second PRS configuration index for the cell of the base station, wherein the first PRS configuration index indicates the period and offset for a first PRS mode, and wherein the second PRS configuration index indicates the period and offset for a second PRS mode. Multiple reference signals (RS) are received from the cell, the RS including a first PRS mode received in a first set of PRS subframes and a second PRS mode received in a second set of PRS subframes; Measure PRS resource units (REs) in the first PRS mode and the second PRS mode, each PRS resource unit including a PRS; and The PRS measurements in each of the first and second PRS modes are sent so that the horizontal and vertical positioning of the UE can be determined based on the measurements. 24. The medium according to claim 23, The prs-Info control signal includes a first PRS configuration and a second PRS configuration. The first PRS configuration and the second PRS configuration respectively indicate the first PRS mode and the second PRS mode, and respectively include the first PRS configuration index and the second PRS configuration index. The first PRS configuration and the second PRS configuration include legacy PRS configuration and non-legacy PRS configuration. The legacy PRS configuration indicates the PRS that can be received by both legacy and non-legacy UEs, and the non-legacy PRS configuration indicates the PRS that can be received by non-legacy UEs. The legacy UEs were configured to communicate using standards prior to version 13 of the 3GPP LTE standard, and Each of the first PRS configuration and the second PRS configuration includes parameters that are independent of the parameters in the other PRS configuration of the first PRS configuration and the second PRS configuration. 25. The medium according to claim 23 or 24, The RS includes a lateral positioning RS and a vertical positioning RS. The lateral positioning RS and the vertical positioning RS include different RS configurations. The one or more processors therein also configure the UE as follows: The reference signal time difference (RSTD) is measured using at least one of the RSs, and The arrival peak (ZOA) of at least one of the RSs and at least one of the precoding matrices are determined, and the ZOA, the at least one of the precoding matrices, and the RSTD provide information to determine the vertical position of the UE. 26. The medium according to claim 23 or 24, wherein the instructions further configure the UE to: The RS is received at different angles, and the RS received at different angles includes different RS configurations; Measure the RS; Determine the specific RS configuration that has the highest value of the measured parameter among the RS configurations of the RS; The specific RS configuration is reported to the location server. 27. A method for determining the horizontal and vertical positioning of a user equipment (UE), comprising: Receive a PRS-Info control signal, wherein the PRS-Info control information includes a first Positioning Reference Signal (PRS) configuration index and a second PRS configuration index for the cell of the base station, wherein the first PRS configuration index indicates the period and offset for a first PRS mode, and wherein the second PRS configuration index indicates the period and offset for a second PRS mode. Multiple reference signals (RS) are received from the cell, the RS including a first PRS mode received in a first set of PRS subframes and a second PRS mode received in a second set of PRS subframes. Measure PRS resource units (REs) in the first PRS mode and the second PRS mode, each PRS resource unit including a PRS; and The PRS measurements in the first PRS mode and the second PRS mode are sent so that the horizontal and vertical positioning of the UE can be determined based on the measurements. 28. The method according to claim 27, The prs-Info control signal includes a first PRS configuration and a second PRS configuration. The first PRS configuration and the second PRS configuration respectively indicate the first PRS mode and the second PRS mode, and respectively include the first PRS configuration index and the second PRS configuration index. The first PRS configuration and the second PRS configuration include legacy PRS configuration and non-legacy PRS configuration. The legacy PRS configuration indicates the PRS that can be received by both legacy and non-legacy UEs, and the non-legacy PRS configuration indicates the PRS that can be received by non-legacy UEs. The legacy UEs were configured to communicate using standards prior to version 13 of the 3GPP LTE standard, and Each of the first PRS configuration and the second PRS configuration includes parameters that are independent of the parameters in the other PRS configuration of the first PRS configuration and the second PRS configuration. 29. The method according to claim 27 or 28, wherein the RS comprises a lateral positioning RS and a vertical positioning RS. At least one of the following is true: a) The lateral positioning RS and the vertical positioning RS include different RS configurations, and the method further includes: At least one of the RSs is used to measure the reference signal time difference (RSTD), and Determine the Zone of Arrival (ZOA) of at least one of the RSs and at least one of the precoding matrices, wherein the ZOA and at least one of the precoding matrices, along with the RSTD, provide information sufficient to determine the vertical position of the UE. b) The method further includes: The RS is received at different angles, and the RS received at different angles includes different RS configurations; Measure the RS; Determine the specific RS configuration that has the highest value of the measured parameter among the RS configurations of the RS; The specific RS configuration is reported to the location server. 30. An apparatus for determining the horizontal and vertical positioning of a user equipment (UE), comprising: A means for receiving a PRS-Info control signal, the PRS-Info control information including a first Positioning Reference Signal (PRS) configuration index and a second PRS configuration index for a cell of a base station, wherein the first PRS configuration index indicates the period and offset for a first PRS mode, and wherein the second PRS configuration index indicates the period and offset for a second PRS mode. A means for receiving multiple reference signals (RS) from the cell, wherein the RS includes a first PRS mode received in a first set of PRS subframes and a second PRS mode received in a second set of PRS subframes. A means for measuring PRS resource units (REs) in the first PRS mode and the second PRS mode, each PRS resource unit including a PRS; and A means for transmitting PRS measurements in the first PRS mode and the second PRS mode so that the horizontal and vertical positioning of the UE can be determined based on the measurements. 31. The device according to claim 30, The prs-Info control signal includes a first PRS configuration and a second PRS configuration. The first PRS configuration and the second PRS configuration respectively indicate the first PRS mode and the second PRS mode, and respectively include the first PRS configuration index and the second PRS configuration index. The first PRS configuration and the second PRS configuration include legacy PRS configuration and non-legacy PRS configuration. The legacy PRS configuration indicates the PRS that can be received by both legacy and non-legacy UEs, and the non-legacy PRS configuration indicates the PRS that can be received by non-legacy UEs. The legacy UEs were configured to communicate using standards prior to version 13 of the 3GPP LTE standard, and Each of the first PRS configuration and the second PRS configuration includes parameters that are independent of the parameters in the other PRS configuration of the first PRS configuration and the second PRS configuration. 32. The device according to claim 30 or 31, The RS includes a lateral positioning RS and a vertical positioning RS. The lateral positioning RS and the vertical positioning RS include different RS configurations. The device also includes: A means for measuring the reference signal time difference (RSTD) using at least one of the RSs, and A means for determining the Zone of Arrival (ZOA) of at least one of the RSs and at least one of the precoding matrices, wherein the ZOA and at least one of the precoding matrices and the RSTD provide information sufficient to determine the vertical position of the UE. 33. The device according to claim 30 or 31, further comprising: A means for receiving the RS at different angles, wherein the RS received at different angles includes different RS configurations; A device for measuring the RS; A means for determining a specific RS configuration in which the measured parameter has the highest value among the RS configurations of the RS; A means for reporting the specific RS configuration to a location server.