Proximity Signaling and Procedure for LTE

• US 20140334388A1
• Filed: 05/08/2013
• Published: 11/13/2014
• Est. Priority Date: 05/08/2013
• Status: Active Grant

• Current Assignee: Blackberry Limited
• Original Assignee: Blackberry Limited
• Inventors: Novak, Robert, Mukherjee, Biswaroop, Ebrahimi Tazeh Mahalleh, Masoud
• Granted Patent: US 9,930,689 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/0055 Physical resource allocation for ACK/NACK for physical mapping arrangements in ARQ protocols H04L1/1861
• CPC Class Codes: H04L 5/0069 Allocation based on distance or geographical location allocation based on terminal or device properties in general, H04W72/51
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 72/1263 Mapping of traffic onto schedule, e.g. scheduled allocation or multiplexing of flows

Abstract

A method for communication in a wireless telecommunications system is provided. The method comprises receiving, by a first UE, a reference signal transmitted by a second UE and transmitting, by the first UE to a network node, a report indicating that the reference signal was received. The reference signal is received in a detection opportunity that occurs as one of a single detection opportunity or a portion of a pattern of detection opportunities.

Claims

1. A method for communication in a wireless telecommunications system, the method comprising:

receiving, by a user equipment (UE), configuration information specifying at least one transmission opportunity in which the UE is to transmit a first reference signal and further specifying at least one parameter applicable to the transmission of the first reference signal; and

transmitting, by the UE, the first reference signal in the specified transmission opportunity;

wherein the configuration information is received via at least one of radio resource control signaling or medium access control signaling, and wherein the transmission opportunity occurs as one of a single transmission opportunity or a portion of a pattern of transmission opportunities.

2. The method of claim 1, further comprising:

attempting, by the UE, to detect a second reference signal that has at least one parameter that is the same as a parameter of the first reference signal, wherein the detection attempt occurs in a detection opportunity that occurs at a different time from the transmission opportunity.

3. The method of claim 1, wherein the at least one parameter is at least one of:

a time/frequency resource;

a cyclic shift;

a code scheme;

a modulation scheme;

or

a root sequence.

4. The method of claim 1, wherein the first reference signal is applied to at least one of:

a sounding reference signal;

a physical random access channel;

a primary synchronization signal;

or

a secondary synchronization signal.

5. The method of claim 1, wherein the configuration information includes an indication of an action the UE is to take for transmission in cases where reference signal transmission is configured to occur when the UE is in a discontinuous reception (DRX) OFF state.

6. The method of claim 2, wherein the transmission opportunity and the detection opportunity occur as a portion of a pattern of transmission opportunities and detection opportunities, and wherein the pattern is configured such that the UE has at least one transmission opportunity to each other UE in a plurality of UEs that includes the UE and has at least one detection opportunity from each other UE.

7. The method of claim 6, wherein the pattern is configured such that a total amount of time for transmission opportunities and detection opportunities is minimized.

8. The method of claim 1, wherein the configuration information is provided to the UE by means of an identifier associated with at least one of the transmission opportunity and the parameter.

9. The method of claim 1, wherein the UE discontinues transmitting the first reference signal upon at least one of:

an expiration of a timer;

or

transmission of the first reference signal a specified number of times.

10. A method for communication in a wireless telecommunications system, the method comprising:

receiving, by a first user equipment (UE), a reference signal transmitted by a second UE; and

transmitting, by the first UE to a network node, a report indicating that the reference signal was received;

wherein the reference signal is received in a detection opportunity that occurs as one of a single detection opportunity or a portion of a pattern of detection opportunities.

11. The method of claim 10, wherein the reference signal is applied to at least one of:

a sounding reference signal;

a physical random access channel;

a primary synchronization signal;

or

a secondary synchronization signal.

12. The method of claim 10, wherein the first UE transmits another reference signal that has at least one parameter that is the same as a parameter of the reference signal transmitted by the second UE, wherein the transmission of the other reference signal occurs in a transmission opportunity that occurs at a different time from the detection opportunity.

13. The method of claim 10, wherein the UE is provided with an indication of an action the UE is to take for detection in cases where reference signal transmission is configured to occur when the UE is in a discontinuous reception (DRX) OFF state.

14. The method of claim 12, wherein the transmission opportunity and the detection opportunity occur as a portion of a pattern of transmission opportunities and detection opportunities, and wherein the pattern is configured such that the first UE has at least one transmission opportunity to each other UE in a plurality of UEs that includes the first UE and has at least one detection opportunity from each other UE.

15. The method of claim 14, wherein the pattern is configured such that a total amount of time for transmission opportunities and detection opportunities is minimized.

16. The method of claim 10, wherein the first UE tracks the second UE by at least one of:

not attempting to detect reference signals from any UEs other than the second UE;

or attempting to detect reference signals from the second UE more frequently than attempting to detect reference signals from UEs other than the second UE.

17. The method of claim 12, wherein the report to the network node includes an identifier associated with at least one of the transmission opportunity and the parameter of the reference signal received by the first UE.

18. The method of claim 10, wherein the first UE attempts to detect at least one of:

all reference signals available to the first UE;

or

a subset of all reference signals available to the first UE, wherein the subset is specified by the network node.

19. The method of claim 18, wherein the reference signals for the first UE to detect are indicated in at least one of:

a system information block (SIB) message broadcast by the network node;

or

a radio resource control message transmitted by the network node.

20. The method of claim 19, wherein the reference signals for the first UE to detect are indicated by specifying resources where the reference signals are transmitted, and wherein the first UE attempts to detect all reference signals in the resources.

21. The method of claim 10, wherein the report provides at least one of:

an indication that the reference signal transmitted by the second UE was detected;

or

an indication of the strength of the reference signal transmitted by the second UE.

22. A network node comprising:

a transmission component configured such that the network node transmits, to a first user equipment (UE), configuration information specifying at least one transmission opportunity in which the first UE is to transmit a reference signal and further specifying at least one parameter applicable to the transmission of the reference signal;

a reception component configured such that the network node receives, from a second UE, a report indicating that the second UE received the reference signal from the first UE; and

a processing component configured such that the network node determines, based on the report, that the first UE is in the proximity of the second UE.

23. The network node of claim 22, wherein the network node transmits to the second UE information indicating that the second UE is in the proximity of the first UE.

24. The network node of claim 22, wherein the at least one parameter is at least one of:

a time/frequency resource;

a cyclic shift;

a code scheme;

a modulation scheme;

or

a root sequence.

25. The network node of claim 22, wherein the network node transmits the configuration information via at least one of radio resource control signaling or medium access control signaling.

26. The network node of claim 22, wherein the network node transmits the configuration information by means of an identifier associated with at least one of the transmission opportunity and the parameter.

27. The network node of claim 22, wherein the network node directs the second UE to detect at least one of:

all reference signals available to the second UE;

or

a subset of all reference signals available to the second UE.

28. The network node of claim 27, wherein the network node indicates the reference signals for the second UE to detect in at least one of:

a system information block (SIB) message;

or

a radio resource control message.

29. The network node of claim 28, wherein the network node indicates the reference signals for the second UE to detect by specifying resources where the reference signals are transmitted, and wherein the second UE attempts to detect all reference signals in the resources.

30. The network node of claim 22, wherein the network node determines the proximity by combining information from a plurality of reports from the second UE.

31. The network node of claim 22, wherein the network node directs the first UE to transmit the reference signal in at least one transmission opportunity and directs the second UE to attempt to detect the reference signal in at least one detection opportunity, wherein the transmission opportunity and the detection opportunity occur as one of:

a single transmission opportunity and a single detection opportunity;

or

a portion of a pattern of transmission opportunities and detection opportunities.

32. The network node of claim 31, wherein, when the transmission opportunity and the detection opportunity occur as a portion of a pattern of transmission opportunities and detection opportunities, the network node configures the pattern such that the first UE and the second UE each have at least one transmission opportunity to each other UE in a plurality of UEs that includes the first UE and the second UE and each have at least one detection opportunity from each other UE.

33. The network node of claim 32, wherein the network node configures the pattern such that a total amount of time for transmission opportunities and detection opportunities is minimized.

34. The network node of claim 22, wherein the network node configures at least one other UE with the same reference signal transmission opportunity and parameters as the first UE.

35. The network node of claim 22, wherein the network node transmits additional configuration information to the first UE at least one time after receiving the report from the second UE, as part of a multiple step proximity detection procedure.

36. The network node of claim 35, wherein the multiple step proximity detection procedure includes the first UE transmitting a first Prox-RS that is also assigned to at least one other UE, the second UE reporting to the network node detection of the first reference signal, the network node assigning to the first UE a second reference signal, the first UE transmitting the second reference signal, and the second UE reporting to the network node detection of the second reference signal.