WO2016099546A1

WO2016099546A1 - Virtual cell based prs transmission for indoor vertical positioning

Info

Publication number: WO2016099546A1
Application number: PCT/US2014/071463
Authority: WO
Inventors: Xiaoyi Wang; Weidong Yang
Original assignee: Nokia Solutions And Networks Oy
Priority date: 2014-12-19
Filing date: 2014-12-19
Publication date: 2016-06-23

Abstract

Various communication devices may benefit from virtual cell based position reference signal (PRS) transmission for indoor vertical positioning. For example, position, signal strength, and knowledge of shaped beams may be beneficial to help identify vertical user position in various indoor environments. A method can include receiving, at a user equipment, configuration parameters from a network node to measure a plurality of position reference signal resources of a cell. The method can also include measuring an arrival time and power for each of the plurality of position reference signal resources. The method can further include reporting the arrival time and power for each of the plurality of position reference signal resources to the network node.

Description

TITLE:

Virtual Cell Based P S Transmission for Indoor Vertical Positioning

BACKGROUND:

Field:

[0001] Various communication devices may benefit from virtual cell based position reference signal (PRS) transmission for indoor vertical positioning. For example, vertical location positioning may be beneficial to help identify vertical user position in various indoor environments.

Description of the Related Art:

[0002] The third generation partnership project (3GPP) has established an indoor positioning study item to enhance long term evolution (LTE) based positioning for indoor scenarios. The main target is to improve the accuracy of positioning in indoor environments for all LTE users.

[0003] A typical indoor scenario may include multi-floor buildings. Vertical location positioning may be especially important in situations where the location of an E91 1 caller is desired.

[0004] Vertical domain positioning may be quite challenging for radio based techniques due to the rich reflection and deflection in indoor environments. To address these challenges, various popular radio based positioning technology may be available. As an example, one radio based positioning technology is known as Observed Time Difference of Arrival (OTDOA). As shown in Figure 1, according to OTDOA, a user equipment (UE) can measure PRS transmitted from multiple cells to detect the arrival time differences. Based on the time difference between multiple cells, the network can calculate the UE's position. Such scheme can be well suitable for detecting a user's horizontal location since radio signal arrival time is mainly determined by radio propagation distance.

[0005] In some scenarios, propagation distance can be determined by the horizontal distance between UE and an evolved NodeB (eNB), or Evolved Universal Mobile Telecommunications System Terrestrial Radio Access Network (eNB, E-UTRAN B). Despite the availability of OTDOA, there are still challenges with obtaining accurate vertical domain positioning data.

SUMMARY:

[0006] According to certain embodiments, a method can include receiving, at a user equipment, configuration parameters from a network node to measure a plurality of position reference signal resources of a cell. The method can also include measuring an arrival time and power for each of the plurality of position reference signal resources. The method can further include reporting the arrival time and power for each of the plurality of position reference signal resources to the network node.

[0007] In certain embodiments, an apparatus can include at least one processor and at least one memory including computer program code. The at least one memory and the computer program code can be configured to, with the at least one processor, cause the apparatus at least to receive, at a user equipment, configuration parameters from a network node to measure a plurality of position reference signal resources of a cell. The at least one memory and the computer program code can also be configured to, with the at least one processor, cause the apparatus at least to measure an arrival time and power for each of the plurality of position reference signal resources. The at least one memory and the computer program code can further be configured to, with the at least one processor, cause the apparatus at least to report the arrival time and power for each of the plurality of position reference signal resources to the network node.

[0008] An apparatus, according to certain embodiments, can include means for receiving, at a user equipment, configuration parameters from a network node to measure a plurality of position reference signal resources of a cell. The apparatus can also include means for measuring an arrival time and power for each of the plurality of position reference signal resources of a cell. The apparatus can further include means for reporting the arrival time and power for each of the plurality of position reference signal resources to the network node.

[0009] A method, in certain embodiments, can include receiving, at a first network node, a request for configuration information for position reference signal resources for a cell from a network node. The method can also include transmitting an identification of a plurality of position reference signal resources of the cell to the second network node. Beam direction of each of the plurality of position reference signal resources can be indicated with the identification.

[0010] According to certain embodiments, an apparatus can include at least one processor and at least one memory including computer program code. The at least one memory and the computer program code can be configured to, with the at least one processor, cause the apparatus at least to receive, at a first network node, a request for configuration information for position reference signal resources for a cell from a second network node. The at least one memory and the computer program code can also be configured to, with the at least one processor, cause the apparatus at least to transmit an identification of a plurality of position reference signal resources of the cell to the second network node. Beam direction of each of the plurality of position reference signal resources is indicated with the identification.

[0011] In certain embodiments, an apparatus can include means for receiving, at a first network node, a request for configuration information for position reference signal resources for a cell from a second network node. The apparatus can also include means for transmitting an identification of a plurality of position reference signal resources of the cell to the second network node. Beam direction of each of the plurality of position reference signal resources can be indicated with the identification.

[0012] A method, according to certain embodiments, can include receiving, at a network node, reports of arrival time, of receiving beam direction, and of power for a plurality of position reference signal resources of a cell. The method can also include calculating a vertical position of a user equipment based on the arrival time, beam direction, and power for the plurality of position reference signal resources. The method can further include reporting or storing the vertical position of the user equipment at the network node.

[0013] An apparatus, in certain embodiments, can include at least one processor and at least one memory including computer program code. The at least one memory and the computer program code can be configured to, with the at least one processor, cause the apparatus at least to receive, at a network node, reports of arrival time, of receiving beam direction, and of power for a plurality of position reference signal resources of a cell. The at least one memory and the computer program code can also be configured to, with the at least one processor, cause the apparatus at least to calculate a vertical position of a user equipment based on the arrival time, beam direction, and power for the plurality of position reference signal resources. The at least one memory and the computer program code can further be configured to, with the at least one processor, cause the apparatus at least to report or store the vertical position of the user equipment at the network node.

[0014] According to certain embodiments, an apparatus can include means for receiving, at a network node, reports of arrival time, of receiving beam direction, and of power for a plurality of position reference signal resources of a cell. The apparatus can also include means for calculating a vertical position of a user equipment based on the arrival time, beam direction, and power for the plurality of position reference signal resources. The apparatus can further include means for reporting or storing the vertical position of the user equipment at the network node.

[0015] In certain embodiments, a non-transitory computer-readable medium can be encoded with instructions that, when executed in hardware, perform a process. The process can include any of the above-described methods. [0016] According to certain embodiments, a computer program product can encode instructions to perform a process. The process can include any of the above-described methods.

[0017] According to certain embodiments, a system can include an apparatus, such as a user equipment, that measures and reports a plurality of position reference signals from a cell, an apparatus such as a network node that provides the position reference signals, and an apparatus such as an E-SMLC that determines a vertical position of a user equipment.

BRIEF DESCRIPTION OF THE DRAWINGS:

[0018] For proper understanding of the invention, reference should be made to the accompanying drawings, wherein:

[0019] Figure 1 illustrates an exemplary radio based positioning technology.

[0020] Figure 2 illustrates a vertical sector based PRS receiving scheme, according to certain embodiments.

[0021] Figure 3 illustrates protocol layers between UE and an evolved serving mobile location center, according to certain embodiments.

[0022] Figure 4 illustrates protocol layers between eNB and an evolved serving mobile location center, according to certain embodiments.

[0023] Figure 5 illustrates a signaling exchange, according to certain embodiments.

[0024] Figure 6 illustrates the generation of multiple PRS resources with different vertical direction, according to certain embodiments.

[0025] Figure 7 illustrates a principle of using beam direction and distance information to calculate UE vertical height, according to certain embodiments.

[0026] Figure 8 illustrates a system according to certain embodiments.

[0027] Figure 9 illustrates a method according to certain embodiments.

[0028] Figure 10 illustrates another method according to certain embodiments.

[0029] Figure 11 illustrates a further method according to certain embodiments.

DETAILED DESCRIPTION:

[0030] Various systems and methods according to certain embodiments can improve the accuracy of positioning in indoor environments for LTE users. A vertical user position can be determined in various ways. For example, according to certain embodiments, vertical user position can be determined using a beam direction based scheme. As shown in Figure 2, using an Active Antenna System (AAS), an evolved Node B (eNB) can formulate multiple virtual vertical sectors on PRS. The PRS in each vertical sector can be precoded with a corresponding precoder in the vertical domain. Additionally, in certain embodiments, the UE can be configured to measure the receiving power and time difference on each virtual sector. Based on the reported receiving power and time difference of each virtual sector, the network can detect the vertical position of the user.

[0031] In certain embodiments, the UE can be configured with multiple PRS resources for the same physical cell. In other embodiments, the UE can be configured with multiple PRS resources from more than one cell. Each PRS resource can have a virtual cell identifier (Virtual Cell ID; VCI). The virtual cell ID can be used to generate the sequence of PRS so that the UE could identify PRS from different virtual cells. The virtual cell ID can also be used solely for generating multiple PRS resources.

[0032] According to certain embodiments, the eNB can transmit each PRS resource based on different vertical precoders. For example, the eNB can transmit an identification of multiple PRS resources. The eNB can also transmit the PRS resource via a vertical beam.

[0033] As shown in Figure 3, the UE can measure and report the arrival time and power for each configured PRS resource for one or multiple cells to an evolved serving mobile location center (E-SMLC) through an LPP(e) interface. Other mechanisms for providing the reported measurements are also permitted.

[0034] As shown in Figure 4, the eNB can report the beam direction of each configured P S resource to the E-SMLC through an LPP(a) interface. For example, in certain embodiments, the eNB can report the beam direction of each configured PRS resource to E-SMLC through the LPPa interface based on the precoder. Further, according to certain embodiments, a beam direction with the largest energy emission can be reported.

[0035] According to certain embodiments, the E-SMLC can select the qualified PRS resources based on the reported receiving PRS power. An example of selection criteria according to certain embodiments can include finding the PRS resource with the largest receiving power within a physical cell. Using the example shown in Figure 2, the system may omit using links 3 and 4 for calculating the user vertical position because the receiving power of P₃ and P₄ are significantly lower than that of Pi and P₂, separately.

[0036] E-SMLC can also calculate user vertical position based on qualified PRS resources and store calculated vertical position. For instance, in the example shown in Figure 2, the direction of Links 1 and 2 are used together with the distance calculated based on Tj and T₂ to calculate user vertical position.

[0037] Figure 5 illustrates a signaling procedure for multiple vertical PRS resources beam based positioning. In certain embodiments, all the information signaled in this procedure can be identified by a virtual cell ID. Physical cell ID may no longer be relevant to the PRS measurement results, but could be included if desired.

[0038] As shown in Figure 5, at 1, E-SMLC can send a request for PRS resource configuration information from the eNB. At 2, eNB can provide the PRS resources configuration, including beam direction, to E-SMLC, in response to the request from E-SMLC. The communication at 1 and 2 can utilize LPPa, as shown in Figure 4. [0039] Next, at 3 in Figure 5, E-SMLC can configure the UE to measure multiple P S resources from multiple cells, such as, for example, two or more cells. For example, the E-SMLC can configure the UE to monitor and report regarding multiple PRS resources for each cell of a plurality of cells.

[0040] At 4, the UE can measure a reference signal time difference (RSTD) and received power for each PRS resource. Finally, at 5, the UE can report RSTD and received power for each PRS resource to the E-SMLC after the RSTD and received power for each PRS resource have been measured. The communication at 3 and 4 can utilize LPPe, as shown in Figure 3.

[0041] Certain embodiments can provide various advantages. For example, according to certain embodiments, elevation beamforming can be used to obtain user vertical position. In other embodiments, the UE can be configured with multiple PRS resources from one physical cell, or multiple cells, such as, for example, two or more cells. For each PRS resource, PRS sequence generation can use a high layer configured virtual cell ID to replace a physical cell ID.

[0042] According to other embodiments, direction reports in the LLPa interface for eNB can be added to report beam direction of each PRS resource. Further, an interface on LLP(e) can be added for UE to report received time and power of each PRS resource.

[0043] Figure 6 illustrates how multiple virtual PRs resources with different vertical sectors can be configured, according to certain embodiments. For example, Figure 6 illustrates how two PRS resources are mapped to an AAS antenna panel with four transceivers. Specifically, PRS-1 can be precoded using F using F₁=(f_{1 1},f_1;2,fi,3,fi_,4), while PRS-2 can be precoded using F₂

The precodhig vector can decide the beam direction for each PRS. With different Fj and F₂, two directional beams can be formulated. Further, in certain embodiments, the eNB can report the main direction of each PRS beam to the E-SMLC, for example as described above in Figure 5.

[0044] Figure 7 illustrates a principle of using beam direction and distance information to calculate UE vertical height, according to certain embodiments. For example, assuming the distance d, beam direction Θ and eNB height H, the UE height h can be calculated as follows: h = cos(#) * d + h.

[0045] When PRS from multiple cells are measured, E-SMLC can calculate the UE height calculated from each cell and average them out. The reliability of the measurement data could be considered during the averaging. For example, measurement from one or more weak link may be given smaller weight during the averaging process or may be omitted from consideration altogether.

[0046] Figure 7 further illustrates a principle of using beam direction and distance information to calculate vertical height, according to certain embodiments. For example, in coordinated multipoint (CoMP) scenarios, different geometrical "cells" may have the same physical cell ID (PCI). In that case, the UE can be configured for a group of PRS resources each with a virtual cell ID. Then, the UE can select one PRS resource from that group to calculate receiving power and time difference. In certain embodiments, multiple PRS resources under one physical cell ID can be automatically considered as a group.

[0047] According to certain embodiments, PRS resources can be configured in various ways. For example, in certain embodiments, one implementation can be to configure PRS resources as group-based. In this example, an eNB can configure PRS resources from the same PCI into one group. In other words, the eNB can configure different VCI from the same cell into one group. Each PRS resource can use a different vertical beam, resulting in a different direction. The UE can be configured with multiple groups of PRS resources. Thus, the UE can down-select the best PRS resource (best reception power) within the group. [0048] Figure 8 illustrates a system according to certain embodiments. In one embodiment, a system may include multiple devices, such as, for example, at least one UE 1 10, at least one E-SMLC 120 and at least one eNB 130 or other base station or access point. eNB 130 may be an example of a network node in certain embodiments. These devices can be operationally interconnected for communication as shown, for example, in Figure 5.

[0049] As shown in Figure 8, each of these devices may include at least one processor, respectively indicated as 1 14, 124 and 134, respectively. At least one memory can be provided in each device, and indicated as 1 15, 125 and 135, respectively. The memory can include computer program instructions or computer code contained therein. The processors 1 14, 124 and 134, and memories 115, 125 and 135, or a subset thereof, can be configured, in certain embodiments, to carry out the operations illustrated in the various blocks of Figures 5 and 9 to 11.

[0050] Furthermore, in other embodiments, an apparatus can include means for receiving, at a user equipment, configuration parameters from a network node to measure a plurality of position reference signal resources of a cell; means for measuring an arrival time and power for each of the plurality of position reference signal resources of a cell; and means for reporting the arrival time and power for each of the plurality of position reference signal resources to the network node. Likewise, in further embodiments, an apparatus can include means for receiving, at a first network node, a request for configuration information for position reference signal resources for a cell from a second network node; and means for transmitting an identification of a plurality of position reference signal resources of the cell to the second network node, wherein beam direction of each of the plurality of position reference signal resources can be indicated with the identification. Similarly, in additional embodiments, an apparatus can include means for receiving, at a network node, reports of arrival time, of receiving beam direction, and of power for a plurality of position reference signal resources of a cell; means for calculating a vertical position of a user equipment based on the arrival time, beam direction, and power for the plurality of position reference signal resources; and means for reporting or storing the vertical position of the user equipment at the network node.

[0051] As shown in Figure 8, transceivers 1 16, 126 and 136 can be provided, and each device may also include an antenna, respectively illustrated as 1 17, 127 and 137. Transceivers 116, 126 and 136 can each, independently, be a transmitter, a receiver, or both a transmitter and a receiver, or a unit device that is configured both for transmission and reception. The transmitter and/or receiver (as far as radio parts are concerned) may also be implemented as a remote radio head which is not located in the device itself, but in a mast, for example. It should also be appreciated that according to the "liquid" or flexible radio concept, the operations and functionalities may be performed in different entities, such as nodes, hosts or servers, in a flexible manner. In other words, division of labor may vary case by case. One possible use is to make a network element to deliver local content. One or more functionalities may also be implemented as a virtual application that is provided as software that can run on a server.

[0052] Processors 1 14, 124 and 134 can be embodied by any computational or data processing device, such as a central processing unit (CPU), application specific integrated circuit (ASIC), or comparable device. The processor can be implemented as a single controller, or a plurality of controllers or processors.

[0053] Memories 115, 125 and 135 can be any suitable storage device, such as a non-transitory computer-readable medium. A hard disk drive (HDD), random access memory (RAM), flash memory, or other suitable memory can be used. The memories can be combined on a single integrated circuit as the processor, or may be separate from the one or more processors. Furthermore, the computer program instructions stored in the memory and which may be processed by the processors can be any suitable form of computer program code, for example, a compiled or interpreted computer program written in any suitable programming language.

[0054] The memory and computer program instructions can be configured, with the processor for the particular device, to cause a hardware apparatus such as UE 1 10, E-SMLC 120 and eNB 130, to perform any of the processes described herein (see, for example, Figures 5 and 9-11). Therefore, in certain embodiments, a non-transitory computer-readable medium can be encoded with computer instructions that, when executed in hardware, perform a process such as one of the processes described herein. Alternatively, certain embodiments of the invention can be performed entirely in hardware.

[0055] Furthermore, although Figure 8 illustrates a system including a UE 1 10, E-SMLC 120 and eNB 130, embodiments of the invention may be applicable to other configurations, and configurations involving additional elements. For example, not shown, additional UEs, E-SMLCs and/or eNBs may be present.

[0056] Figure 9 illustrates a method according to certain embodiments. The method may provide an option for positioning of a user device. The method may be applied in positioning of a user device in a building that includes a plurality of floors. For example, the method may provide enhanced accuracy in three dimensional positioning as contrasted with prior multilateration techniques. The method of Figure 9 may be performed by, for example, UE 1 10 in Figure 8. Furthermore, the method of Figure 9 may be beneficially used in combination with the methods of Figures 10 and 11, to provide accurate vertical positioning for users in multi-story buildings.

[0057] As shown in Figure 9, a method can include, at 210, receiving, at a user equipment, configuration parameters from a network node to measure a plurality of position reference signal resources of a cell. These can be received over LPPe. Thus, in certain embodiments, the network node may be an E- SMLC. The method can also include, at 220, measuring an arrival time and power for each of the plurality of position reference signal resources. The method can further include, at 230, reporting the arrival time and power for each of the plurality of position reference signal resources to the network node. The measuring and reporting can be for each of the plurality of position reference signal resources for multiple cells to the network node. These reports can be made along the lines described above, and can include, for example, a virtual cell ID to identify the position reference signal resources.

[0058] Figure 10 illustrates another method according to certain embodiments. The method of Figure 10 may be performed by, for example, an eNB 130 as shown in Figure 8.

[0059] As shown in Figure 10, a method can include, at 310, receiving, at a network node such as a base station, a request for configuration information for position reference signal resources from a network node, such as an E- SMLC. Thus, the request may be received over LPPa. The method can also include, at 320, transmitting an identification of a plurality of position reference signal resources to the network node. The identification can provide information regarding the resources, such as beamforming direction. The method can further include, at 330, formulating a plurality of virtual vertical sectors based on the plurality of reference signal resources.

[0060] The method can also include, at 340, determining the beam direction by the first network node. Alternatively, the method can further include, at 350, receiving instructions for the beam direction from the second network node. The method can additionally include, at 355, setting the beam direction based on the instructions or the determination.

[0061] Figure 11 illustrates a further method according to certain embodiments. The method of Figure 1 1 may be performed, for example, by an E-SMLC.

[0062] As shown in Figure 11, a method can include, at 410, sending a request for configuration information for a plurality of position reference signal resources to a network node. This can be the same request received at 310 in Figure 10 and shown at 1 in Figure 5. In certain embodiments, the network node may be an eNB.

[0063] As shown in Figure 1 1, the method can also include, at 420, receiving an identification of the plurality of position reference signal resources from the network node. This may be the same resources shown at 2 in Figure 5 and at 320 in Figure 10. The resources may be identified by virtual cell ID and may include beam direction information for each of the position reference signal resources.

[0064] As shown in Figure 1 1, the method can further include, at 430, sending configuration parameters to a UE to measure the plurality of position reference signal resources. These can be the same parameters received at 210 in Figure 9 and at 3 in Figure 5.

[0065] The method, as shown in Figure 1 1, can also include, at 440, receiving, at an evolved serving mobile location center, a report of arrival time and power for the plurality of position reference signal resources of a cell. The plurality of position reference signal resources may include reports of multiple cells, each having a respective plurality of position reference signal resources. The resources may be identified by a virtual cell identifier, or similar indicator. Thus, the E-SMLC may be able to identify beamforming direction corresponding to the received reports.

[0066] The method can further include, at 450, selecting qualified position reference signal resources based on the power report. The selection of qualified resources may, as described above, be based on the relative strength of the resources, with the selection favoring stronger signals over weaker signals.

[0067] The method can also include, at 460, calculating a vertical position of the UE based on the arrival time and power for the plurality of position reference signal resources. The method can further include, at 470, storing the vertical position of the UE at the evolved serving mobile location center. [0068] The method can further include, at 480, instructing the cell regarding the beam direction for the plurality of position reference signals. The numbering of the method should not be taken as implying the ordering. For example, the instructing regarding the beam direction can occur prior to receiving the plurality of position reference signal resources at 420. Furthermore, the receiving the report of arrival time and power at 440 can occur together with the receiving at 420, among other options.

[0069] The various methods and systems described above can be used in combination with one another. Thus, each of the steps should be understood to be usable in combination with the others or optionally to be omitted, in certain embodiments. Furthermore, the steps may be combined in a variety of ways. For example, the P S resources can be reported together with the information regarding beam direction for the PRS resources or can be reported separately from them. In certain embodiments, a UE can report the received power and arrival time for the PRS resources, while an eNB can report the beam direction for the PRS resources.

[0070] The various options of the methods according to each of Figures 9, 10, and 11 , can be used in combination with one another or separately from one another. Furthermore, the methods of Figures 9-1 1 may be modified as described above with reference to Figures 2-7 and may be performed with a system, such as that shown in Figure 8. Other modifications and alterations are permitted.

[0071] In the preceding discussion, different exemplifying embodiments have been described using, as an example of an access architecture to which the embodiments may be applied, a radio access architecture based on long term evolution advanced (LTE Advanced, LTE-A) or other architectures related to the third generation partnership project (3 GPP). Certain embodiments are not restricted to such an architecture. For instance, Figures 3-5 depict examples of simplified system architectures only showing some elements and functional entities, all being logical units, whose implementation may differ from what is shown. The connections shown in Figure 3-5 are logical connections; the actual physical connections may be different. Moreover, a system may also include other functions and structures than those shown in Figures 3-5.

[0072] The embodiments are not restricted to the systems given as examples but the solutions and approaches described can be applied to other communication systems provided with suitable properties. Another example of a suitable communications system is the 5G concept. The network architecture in 5G may be similar to that of LTE-A. There may also be differences. For example, 5G may use multiple input - multiple output (MIMO) antennas, many more base stations or nodes than LTE (a so-called small cell concept), including macro sites operating in co-operation with smaller stations and perhaps also employing a variety of radio technologies for better coverage and enhanced data rates.

[0073] Furthermore, networks may utilize network functions virtualization (NFV) which is a network architecture concept that proposes virtualizing network node functions into "building blocks" or entities that may be operationally connected or linked together to provide services. A virtualized network function (VNF) may comprise one or more virtual machines running computer program codes using standard or general type servers instead of customized hardware. Cloud computing or data storage may also be utilized. In radio communications this may mean node operations can be carried out, at least partly, in a server, host or node operationally coupled to a remote radio head. It is also possible that node operations will be distributed among a plurality of servers, nodes or hosts. It should also be understood that the distribution of labor between core network operations and base station operations may differ from that of the LTE or even be non-existent.

[0074] One having ordinary skill in the art will readily understand that the invention as discussed above may be practiced with steps in a different order, and/or with hardware elements in configurations which are different than those which are disclosed. Therefore, although the invention has been described based upon these preferred embodiments, it would be apparent to those of skill in the art that certain modifications, variations, and alternative constructions would be apparent, while remaining within the spirit and scope of the invention. In order to determine the metes and bounds of the invention, therefore, reference should be made to the appended claims.

[0075] Glossary

[0076] 3 GPP Third Generation Partnership Project

[0077] AAS Active Antenna System

[0078] ASIC Application Specific Integrated Circuit

[0079] CoMP Coordinated Multipoint

[0080] CPU Central Processing Unit

[0081] eNB Evolved NodeB

[0082] E-SMLC Evolved serving Mobile Location Center

[0083] E-UTRAN Evolved UMTS Terrestrial Radio Access Network

[0084] UMTS Universal Mobile Telecommunications System

[0085] HDD Hard Disk Drive

[0086] ID Identifier

[0087] LTE Long Term Evolution

[0088] OTDOA Observed Time Difference of Arrival

[0089] PCI Physical Cell ID

[0090] PRS Position Reference Signal

[0091] RAM Random Access Memory

[0092] UE User Equipment

[0093] VCI Virtual Cell ID

Claims

WE CLAIM:

1. A method, comprising:

receiving, at a user equipment, configuration parameters from a network node to measure a plurality of position reference signal resources of a cell;

measuring an arrival time and power for each of the plurality of position reference signal resources; and

reporting the arrival time and power for each of the plurality of position reference signal resources to the network node.

2. The method of claim 1, wherein the configuration parameters are received from a plurality of cells, each cell of the plurality of cells having a plurality of position reference signal resources.

3. The method of claim 1, wherein each of the configuration parameters comprises a virtual cell identification.

4. The method of claim 1, wherein reporting is performed through an LPP(e) interface.

5. The method of claim 1, wherein the configuration parameters are received from at least three cells.

6. An apparatus, comprising:

means for receiving, at a user equipment, configuration parameters from a network node to measure a plurality of position reference signal resources of a cell;

means for measuring an arrival time and power for each of the plurality of position reference signal resources of a cell; and

means for reporting the arrival time and power for each of the plurality of position reference signal resources to the network node.

7. The apparatus of claim 6, wherein the configuration parameters are received from a plurality of cells, each cell of the plurality of cells having a plurality of position reference signal resources.

8. The apparatus of claim 6, wherein each of the configuration parameters comprises a virtual cell identification.

9. The apparatus of claim 6, wherein reporting is performed through an LPP(e) interface.

10. The apparatus of claim 6, wherein the configuration parameters are received from at least three cells.

1 1. A method, comprising:

receiving, at a first network node, a request for configuration information for position reference signal resources for a cell from a second network node; and

transmitting an identification of a plurality of position reference signal resources of the cell to the second network node,

wherein beam direction of each of the plurality of position reference signal resources is indicated with the identification.

12. The method of claim 11, wherein the second network node comprises an E-SMLC.

13. The method of claim 11, wherein the request is received and the identification is transmitted via an LPPa interface.

14. The method of claim 1 1, further comprising formulating a plurality of virtual vertical sectors based on the plurality of reference signal resources.

15. The method of claim 11, wherein each of the virtual vertical sectors is precoded with a corresponding precoder in vertical domain.

16. The method of claim 1 1 , wherein each of the plurality of reference signal resources are transmitted based on different vertical precoders.

17. The method of claim 1 1, wherein the beam direction information is reported based on the precoder.

18. The method of claim 1 1, wherein each of the plurality of position reference signal resources comprises beam direction information.

19. The method of claim 1 1, further comprising:

determining the beam direction by the first network node.

20. The method of claim 1 1, further comprising:

receiving instructions for the beam direction from the second network node; and

setting the beam direction based on the instructions.

21. An apparatus, comprising:

means for receiving, at a first network node, a request for configuration information for position reference signal resources for a cell from a second network node; and

means for transmitting an identification of a plurality of position reference signal resources of the cell to the second network node,

22. The apparatus of claim 21, wherein the second network node comprises an E-SMLC.

23. The apparatus of claim 21, wherein the request is received and the identification is transmitted via an LPPa interface.

24. The apparatus of claim 21, further comprising means for formulating a plurality of virtual vertical sectors based on the plurality of reference signal resources.

25. The apparatus of claim 21, wherein each of the virtual vertical sectors is precoded with a corresponding precoder in vertical domain.

26. The apparatus of claim 21, wherein each of the plurality of reference signal resources are transmitted based on different vertical precoders.

27. The apparatus of claim 21, wherein the beam direction information is reported based on the precoder.

28. The apparatus of claim 21 , wherein each of the plurality of position reference signal resources comprises beam direction information.

29. The apparatus of claim 21, further comprising:

means for determining the beam direction by the first network node.

30. The apparatus of claim 21, further comprising:

means for receiving instructions for the beam direction from the second network node; and

means for setting the beam direction based on the instructions.

31. A method, comprising:

receiving, at a network node, reports of arrival time, of receiving beam direction, and of power for a plurality of position reference signal resources of a cell;

calculating a vertical position of a user equipment based on the arrival time, beam direction, and power for the plurality of position reference signal resources; and

reporting or storing the vertical position of the user equipment at the network node.

32. The method of claim 31 , wherein reports of the receiving beam direction are received from a network node through an LPPa interface.

33. The method of claim 31, wherein reports of the arrival time and the power are received from a user equipment through an LPPe interface.

34. The method of claim 31 , further comprising, sending a request for configuration information for the plurality of position reference signal resources to a network node.

35. The method of claim 31, further comprising receiving the plurality of position reference signal resources from the network node.

36. The method of claim 31, further comprising sending configuration parameters to the user equipment to measure the plurality of position reference signal resources.

37. The method of claim 31, further comprising selecting qualified position reference signal resources based on the power report.

38. The method of claim 31, wherein the position reference signal resources with the largest receiving power within a physical cell are selected as the qualified position reference signal resources.

39. The method of claim 31, wherein the vertical position of the user equipment is calculated based on the qualified position reference signal resources.

40. The method of claim 31 , further comprising:

instructing the cell regarding the beam direction for the plurality of position reference signals.

41. An apparatus, comprising:

means for receiving, at a network node, reports of arrival time, of receiving beam direction, and of power for a plurality of position reference signal resources of a cell;

means for calculating a vertical position of a user equipment based on the arrival time, beam direction, and power for the plurality of position reference signal resources; and

means for reporting or storing the vertical position of the user equipment at the network node.

42. The apparatus of claim 41, wherein reports of the receiving beam direction are received from a network node through an LPPa interface.

43. The apparatus of claim 41, wherein reports of the arrival time and the power are received from a user equipment through an LPPe interface.

44. The apparatus of claim 41, further comprising means for sending a request for configuration information for the plurality of position reference signal resources to a network node.

45. The apparatus of claim 41, further comprising means for receiving the plurality of position reference signal resources from the network node.

46. The apparatus of claim 41, further comprising means for sending configuration parameters to the user equipment to measure the plurality of position reference signal resources.

47. The apparatus of claim 41, further comprising means for selecting qualified position reference signal resources based on the power report.

48. The apparatus of claim 41, wherein the position reference signal resources with the largest receiving power within a physical cell are selected as the qualified position reference signal resources.

49. The apparatus of claim 41 , wherein the vertical position of the user equipment is calculated based on the qualified position reference signal resources.

50. The apparatus of claim 41, further comprising:

means for instructing the cell regarding the beam direction for the plurality of position reference signals.