Methods and apparatus for positioning measurement in multi-antenna transmission systems

• US 9,204,418 B2
• Filed: 01/30/2014
• Issued: 12/01/2015
• Est. Priority Date: 05/03/2010
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Siomina, Iana, Seln, Yngve
• Primary Examiner(s): Batista, Marcos
• Application Number:
  US14/168,250
• Publication Number:
  US 20140148198A1
• Time in Patent Office: 670 Days
• Field of Search: 455/556.1, 4554561-4563
• US Class Current: 1/1
• CPC Class Codes: G01S 5/10 Position of receiver fixed by co-ordinating a plurality of position lines defined by path-difference measurements , e.g. omega or decca systemsG01S5/12 takes precedence ; beacons and receivers cooperating therewith G01S1/306, G01S1/308
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

This document discloses solutions for using a mix of reference signal types in a wireless communications network, e.g., a first type and a second type, in making positioning-related measurements. In one example, a UE uses a “mix” of CRS and PRS. As an example case, a UE receives PRS and, possibly, CRS from one or more cells, while it receives only CRS from one or more other cells. In this case, the UE determines, e.g., received signal timing values for CRS as received from some cells, on a per-cell basis, and for PRS as received from other cells, on a per-cell basis. The UE can measure and report on per-signal/per-cell basis and can perform calculations involving a mix of timing measurements made for both CRS and PRS. In a further aspect, reference signal transmissions are controlled or coordinated on a per-port basis in cells that use multiple antenna ports for transmitting within each such cell.

Claims

1. A method of performing positioning-related measurements in a wireless communication apparatus associated with a wireless communication network, said method comprising:

receiving a first type of reference signals that are transmitted from more than one antenna port at a time within a cell in said wireless communication network, wherein a plurality of antenna ports are used for transmitting in said cell;

receiving a second type of reference signals that are transmitted from only one antenna port at a time within the cell; and

making positioning-related measurements with respect to said first and second types of reference signals for said cell, on a per-port basis.

2. The method of claim 1, further comprising receiving assistance information for said cell that includes at least one of:

information indicating which one or ones in said plurality of antenna ports are used for transmitting the second type of reference signals over one or more defined transmission occasions;

information indicating a dynamic pattern defining which particular antenna port among the plurality of antenna ports that is used during any given transmission occasion for transmitting the second type of reference signals; and

information indicating a muting pattern used to mute transmission of the second type of reference signals at certain ones of the transmission occasions, wherein said muting pattern applies to a given one of said antenna ports over a succession of said transmission occasions, or applies to multiple antenna ports among said plurality of antenna ports that are used one at a time according to a defined sequence, to transmit the second type of reference signals over said succession of said transmission occasions.

3. The method of claim 1, further comprising receiving muting configuration information on a per-port basis for one or more of said plurality of antenna ports, and controlling searching for or measurement of the second type of reference signals with respect to said one or more of said antenna ports, based on said muting configuration information.

4. The method of claim 1, further comprising receiving assistance data that includes information indicating positions of the antenna ports in said plurality of antenna ports, and using said indicated positions to determine a location of said wireless communication apparatus based on said indicated positions and based on said positioning-related measurements performed on said per-port basis.

5. The method of claim 1, wherein said first type of reference signals are cell-specific reference signals, “

CRS”

, that are transmitted for channel estimation and said second type of reference signals are positioning reference signals, “

PRS”

, that are transmitted explicitly for positioning measurements.

6. The method of claim 1, wherein said first type of reference signals comprises reference signals on which the wireless communication apparatus is capable of performing positioning-related measurements without measurement ambiguity even if those reference signals are transmitted from more than one antenna port at a time within a cell, and wherein said second type of reference signals comprises reference signals on which the wireless communication apparatus is capable of performing positioning-related measurements without measurement ambiguity only if those reference signals are transmitted from one antenna port at a time within a cell.

7. The method of claim 1, wherein the second type of reference signals are transmitted from only one antenna port in any given positioning occasion within the cell, wherein a positioning occasion comprises one or more consecutive subframes.

8. The method of claim 7, wherein said second type of reference signals are positioning reference signals, “

PRS”

, that are transmitted explicitly for positioning measurements, and wherein the one or more consecutive subframes are one or more consecutive Long Term Evolution (LTE) subframes in which PRS are transmitted.

9. A wireless communication apparatus that is configured for performing positioning-related measurements on reference signals transmitted in a cell in a wireless communication network, said wireless communication apparatus comprising:

a receiver configured to receive a first type of reference signals that are transmitted from more than one antenna port at a time within said cell, wherein a plurality of antenna ports are used for transmitting in said cell, and to receive a second type of reference signals that are transmitted from only one antenna port at a time within the cell; and

a receiver processing circuit configured to make positioning-related measurements with respect to said first and second types of reference signals for said cell, on a per-port basis.

10. The wireless communication apparatus of claim 9, wherein said wireless communication apparatus is configured to receive and respond to assistance information for said cell that includes at least one of:

information indicating which one or ones in said plurality of antenna ports are used for transmitting the second type of reference signals over one or more defined transmission occasions;

information indicating a dynamic pattern defining which particular antenna port among the plurality of antenna ports that is used during any given transmission occasion for transmitting the second type of reference signals; and

information indicating a muting pattern used to mute transmission of the second type of reference signals at certain ones of the transmission occasions, wherein said muting pattern applies to a given one of said antenna ports over a succession of said transmission occasions, or applies to multiple antenna ports among said plurality of antenna ports that are used one at a time according to a defined sequence, to transmit the second type of reference signals over said succession of said transmission occasions.

11. The wireless communication apparatus of claim 9, wherein said wireless communication apparatus is configured to receive muting configuration information on a per-port basis for one or more of said plurality of antenna ports, and to control searching for or measurement of the second type of reference signals with respect to said one or more of said antenna ports, based on said muting configuration information.

12. The wireless communication apparatus of claim 9, wherein said wireless communication apparatus is configured to receive assistance data that includes information indicating positions of the antenna ports in said plurality of antenna ports, and to use said indicated positions to determine a location of said wireless communication apparatus based on said indicated positions and based on said positioning-related measurements performed on said per-port basis.

13. The wireless communication apparatus of claim 9, wherein said first type of reference signals are cell-specific reference signals, “

CRS”

, that are transmitted for channel estimation and said second type of reference signals are positioning reference signals, “

PRS”

, that are transmitted explicitly for positioning measurements.

14. The wireless communication apparatus of claim 9, wherein said first type of reference signals comprises reference signals on which the wireless communication apparatus is capable of performing positioning-related measurements without measurement ambiguity even if those reference signals are transmitted from more than one antenna port at a time within a cell, and wherein said second type of reference signals comprises reference signals on which the wireless communication apparatus is capable of performing positioning-related measurements without measurement ambiguity only if those reference signals are transmitted from one antenna port at a time within a cell.

15. The wireless communication apparatus of claim 9, wherein the second type of reference signals are transmitted from only one antenna port within any given positioning occasion within the cell, wherein a positioning occasion comprises one or more consecutive subframes.

16. The wireless communication apparatus of claim 15, wherein said second type of reference signals are positioning reference signals, “

PRS”

, that are transmitted explicitly for positioning measurements, and wherein the one or more consecutive subframes are one or more consecutive Long Term Evolution (LTE) subframes in which PRS are transmitted.

17. A method of controlling positioning reference signal transmission from multiple antenna ports within each of one or more cells of a wireless communication network, said method performed by a reference signal controller associated with said wireless communication network and said method comprising:

coordinating transmission of positioning reference signals from multiple antenna ports, one antenna port at a time, within each such cell to wireless communication apparatuses that are measuring or will measure, on a per-port basis, the positioning reference signals transmitted in said cells; and

sending corresponding signaling to at least one of;

the base stations involved in said step of coordinating, and said wireless communication apparatuses.

18. The method of claim 17, wherein said coordinating comprises deciding at the reference signal controller at least one of:

a pattern to use for transmitting a positioning reference signal from different antenna ports, one antenna port at a time, within each said cell; and

a pattern for muting the transmission of positioning reference signals across said cells.

19. The method of claim 17, wherein said positioning reference signals comprises reference signals on which each of said wireless communication apparatuses is capable of performing positioning-related measurements without measurement ambiguity only if those reference signals are transmitted from one antenna port at a time within a cell.

20. The method of claim 17, wherein said coordinating comprises coordinating the transmission of positioning reference signals from different antenna ports in different respective positioning occasions within each such cell, such that positioning signals are transmitted from one antenna port in any given positioning occasion within each such cell, wherein a positioning occasion comprises one or more consecutive subframes in which positioning reference signals are transmitted.

21. The method of claim 20, wherein the one or more consecutive subframes are one or more consecutive Long Term Evolution (LTE) subframes.

22. A reference signal controller configured to control positioning reference signal transmission from multiple antenna ports within each of one or more cells of a wireless communication network, said reference signal controller comprising:

processing circuitry configured to coordinate transmission of positioning reference signals from multiple antenna ports, one antenna port at a time, within each such cell to wireless communication apparatuses that are measuring or will measure, on a per-port basis, the positioning reference signals transmitted in said cells; and

one or more communication interfaces configured to send corresponding signaling to at least one of;

the base stations involved in said coordination, and said wireless communication apparatuses.

23. The reference signal controller of claim 22, wherein said reference signal controller is configured to coordinate said transmission of positioning reference signals based on deciding at the reference signal controller at least one of:

a pattern to use for transmitting a positioning reference signal from different antenna ports, one antenna port at a time, within each said cell; and

a pattern for muting the transmission of positioning reference signals across said cells.

24. The reference signal controller of claim 22, wherein said positioning reference signals comprises reference signals on which each of said wireless communication apparatuses is capable of performing positioning-related measurements without measurement ambiguity only if those reference signals are transmitted from one antenna port at a time within a cell.

25. The reference signal controller of claim 22, wherein the processing circuitry is configured to coordinate transmission of positioning reference signals from different antenna ports in different respective positioning occasions within each such cell, such that positioning signals are transmitted from one antenna port in any given positioning occasion within each such cell, wherein a positioning occasion comprises one or more consecutive subframes in which positioning reference signals are transmitted.

26. The reference signal controller of claim 25, wherein the one or more consecutive subframes are one or more consecutive Long Term Evolution (LTE) subframes.