VARIABLE LENGTH REFERENCE SIGNALING FOR FAST ACQUISITION IN SHARED SPECTRUM

• US 20180241494A1
• Filed: 02/19/2018
• Published: 08/23/2018
• Est. Priority Date: 02/21/2017
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Chendamarai Kannan, Arumugam, Patel, Chirag Sureshbhai, Luo, Tao, Kadous, Tamer Adel
• Granted Patent: US 10,700,802 B2
• Time in Patent Office: Days
• CPC Class Codes: H04B 7/0695 using beam selection
• CPC Class Codes: H04J 11/0073 Acquisition of primary synchronisation channel, e.g. detection of cell-ID within cell-ID group
• CPC Class Codes: H04J 11/0076 Acquisition of secondary synchronisation channel, e.g. detection of cell-ID group
• CPC Class Codes: H04J 2211/005 Long term evolution [LTE]
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0098 Signalling of the activation or deactivation of component carriers, subcarriers or frequency bands
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 56/001 Synchronization between nodes

Abstract

Methods, systems, and devices for wireless communication are described. A base station may configure bursts of synchronization signal (SS) blocks for discovery reference signal (DRS) transmission. The base station may transmit an SS block set in an SS burst according to a beam sweep pattern, which may be repeated for a subsequent SS block set. The base station may configure a number of SS block sets in each SS burst and transmit each SS block in an SS block set using a different beam. Each SS burst may be transmitted according to a different beam sweep pattern and the base station may repeat transmission of SS bursts according to a DRS repetition periodicity. A user equipment (UE) may sweep through antenna sub-arrays during reception of an SS burst to determine a suitable sub-array for communication.

Claims

1. A method for wireless communication, comprising:

determining a first discovery reference signal (DRS) interval for a shared radio frequency spectrum band;

determining a first set of synchronization signal (SS) blocks to be transmitted in a first variable length SS burst based at least in part on a first set of transmission beams; and

transmitting, using one or more transmission beams of the first set of transmission beams, the first variable length SS burst during the first DRS interval for the shared radio frequency spectrum band.

2. The method of claim 1, further comprising:

determining a second DRS interval for the shared radio frequency spectrum band, wherein the second DRS interval is after the first DRS interval;

determining a second set of SS blocks to be transmitted in a second variable length SS burst based at least in part on a second set of transmission beams; and

transmitting, using one or more transmission beams of the second set of transmissions beams, the second variable length SS burst during the second DRS interval for the shared radio frequency spectrum band.

3. The method of claim 2, further comprising:

transmitting a third variable length SS burst in a third DRS interval based at least in part on a DRS repetition periodicity.

4. The method of claim 3, wherein the third variable length SS burst is a repetition of the first variable length SS burst.

5. The method of claim 1, wherein transmitting the first variable length SS burst comprises:

transmitting the first set of SS blocks according to a beam sweep pattern.

6. The method of claim 5, further comprising:

repeating the beam sweep pattern multiple times in the first variable length SS burst, wherein the first set of SS blocks comprises multiple SS block sets and each of the multiple SS block sets spans a nominal SS period.

7. The method of claim 1, wherein transmitting the first variable length SS burst comprises:

transmitting using each of the first set of transmission beams.

8. The method of claim 1, further comprising:

transmitting, using one or more transmission beams of the first set of transmission beams, an opportunistic DRS during the first DRS interval.

9. The method of claim 1, further comprising:

selecting multiple beams from the first set of transmission beams based at least in part on a DRS initiation request message received from a user equipment (UE); and

performing a beam refinement procedure with the UE based at least in part on the multiple beams, wherein performing the beam refinement procedure comprises transmitting a signature on each of the multiple beams.

10. The method of claim 1, wherein the SS blocks of the first set of SS blocks and the second set of SS blocks each comprise a physical broadcast channel (PBCH) message, a primary synchronization signal (PSS), a secondary synchronization signal (SSS), or any combination thereof.

11. A method for wireless communication, comprising:

determining a discovery reference signal (DRS) interval for a shared radio frequency spectrum band;

receiving, using a first antenna sub-array, a first set of synchronization signal (SS) blocks of an SS burst during the DRS interval;

receiving, using a second antenna sub-array, a second set of SS blocks of the SS burst during the DRS interval;

determining to use the first antenna sub-array or the second antenna sub-array for communication with a base station based at least in part on the received first set of SS blocks and the received second set of SS blocks; and

communicating with the base station based at least in part on the determining.

12. The method of claim 11, wherein the first set of SS blocks is received over a first time interval of a fixed length and the second set of SS blocks is received over a second time interval of the fixed length.

13. The method of claim 11, wherein the first set of SS blocks comprises a repetition of at least one SS block.

14. The method of claim 11, further comprising:

performing a beam refinement procedure with the base station based at least in part on one or both of the received first set of SS blocks and the received second set of SS blocks.

15. The method of claim 11, wherein the first set of SS blocks and the second set of SS blocks comprise at least one common SS block.

16. An apparatus for wireless communication, in a system comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory, wherein the instructions are executable by the processor to;

determine a first discovery reference signal (DRS) interval for a shared radio frequency spectrum band;

determine a first set of synchronization signal (SS) blocks to be transmitted in a first variable length SS burst based at least in part on a first set of transmission beams; and

transmit, using one or more transmission beams of the first set of transmission beams, the first variable length SS burst during the first DRS interval for the shared radio frequency spectrum band.

17. The apparatus of claim 16, wherein the instructions are further executable by the processor to:

determine a second DRS interval for the shared radio frequency spectrum band, wherein the second DRS interval is after the first DRS interval;

determine a second set of SS blocks to be transmitted in a second variable length SS burst based at least in part on a second set of transmission beams; and

transmit, using one or more transmission beams of the second set of transmissions beams, the second variable length SS burst during the second DRS interval for the shared radio frequency spectrum band.

18. The apparatus of claim 17, wherein the instructions are further executable by the processor to:

transmit a third variable length SS burst in a third DRS interval based at least in part on a DRS repetition periodicity.

19. The apparatus of claim 18, wherein the third variable length SS burst is a repetition of the first variable length SS burst.

20. The apparatus of claim 16, wherein the instructions executable by the processor to transmit the first variable length SS burst comprise instructions executable by the processor to:

transmit the first set of SS blocks according to a beam sweep pattern.

21. The apparatus of claim 20, wherein the instructions are further executable by the processor to:

repeat the beam sweep pattern multiple times in the first variable length SS burst, wherein the first set of SS blocks comprises multiple SS block sets and each of the multiple SS block sets spans a nominal SS period.

22. The apparatus of claim 16, wherein the instructions executable by the processor to transmit the first variable length SS burst comprise instructions executable by the processor to:

transmit using each of the first set of transmission beams.

23. The apparatus of claim 16, wherein the instructions are further executable by the processor to:

transmit, using one or more transmission beams of the first set of transmission beams, an opportunistic DRS during the first DRS interval.

24. The apparatus of claim 16, wherein the instructions are further executable by the processor to:

select multiple beams from the first set of transmission beams based at least in part on a DRS initiation request message received from a user equipment (UE); and

perform a beam refinement procedure with the UE based at least in part on the multiple beams, wherein performing the beam refinement procedure comprises transmitting a signature on each of the multiple beams.

25. The apparatus of claim 16, wherein the SS blocks of the first set of SS blocks and the second set of SS blocks each comprise a physical broadcast channel (PBCH) message, a primary synchronization signal (PSS), a secondary synchronization signal (SSS), or any combination thereof.

26. An apparatus for wireless communication, in a system comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory, wherein the instructions are executable by the processor to;

determine a discovery reference signal (DRS) interval for a shared radio frequency spectrum band;

receive, using a first antenna sub-array, a first set of synchronization signal (SS) blocks of an SS burst during the DRS interval;

receive, using a second antenna sub-array, a second set of SS blocks of the SS burst during the DRS interval;

determine to use the first antenna sub-array or the second antenna sub-array for communication with a base station based at least in part on the received first set of SS blocks and the received second set of SS blocks; and

communicate with the base station based at least in part on the determining.

27. The apparatus of claim 26, wherein the first set of SS blocks is received over a first time interval of a fixed length and the second set of SS blocks is received over a second time interval of the fixed length.

28. The apparatus of claim 26, wherein the first set of SS blocks comprises a repetition of at least one SS block.

29. The apparatus of claim 26, wherein the instructions are further executable by the processor to:

perform a beam refinement procedure with the base station based at least in part on one or both of the received first set of SS blocks and the received second set of SS blocks.

30. The apparatus of claim 26, wherein the first set of SS blocks and the second set of SS blocks comprise at least one common SS block.