SYNCHRONIZATION CHANNEL AND SYSTEM ACQUISITION FOR INTERNET OF THINGS COMMUNICATIONS IN A SHARED SPECTRUM

• US 20180368089A1
• Filed: 05/25/2018
• Published: 12/20/2018
• Est. Priority Date: 06/15/2017
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Yerramalli, Srinivas, Chendamarai Kannan, Arumugam, Liu, Chih-Hao, Kadous, Tamer
• Granted Patent: US 11,051,263 B2
• Time in Patent Office: Days
• CPC Class Codes: H04J 11/0069 Cell search, i.e. determining cell identity [cell-ID] design of multiplexing codes H04J13/00; processing access restriction or access information H04W48/16; discovery of network devices for network data management H04W8/005; sounding signals for channel estimation H04L25/0226; structure of reference signals in multicarrier modulation systems H04L27/2613; frame, time or carrier synchronisation in multicarrier modulation systems H04L27/2655
• 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 2011/0096 Network synchronisation
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 27/2614 Peak power aspects
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 56/0015 one node acting as a reference for the others
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/27 between access points

Abstract

Methods, systems, and devices for wireless communication are described. A base station may identify a first synchronization sequence and generate a second synchronization sequence based at least in part on the first synchronization sequence. The base station may map the first synchronization sequence to a first resource block of a synchronization channel associated with a first frequency sub-band of a shared radio frequency spectrum band and the second synchronization sequence to a second resource block associated with a second frequency sub-band of the synchronization channel. The base station may then transmit the first synchronization sequence and the second synchronization sequence concurrently over the synchronization channel using the first resource block and the second resource block according to the mapping. In some cases, the second synchronization may be generated by applying a first phase shift to the first synchronization sequence.

Claims

1. A method for wireless communication, comprising:

identifying a first synchronization sequence;

generating a second synchronization sequence based at least in part on the first synchronization sequence;

mapping the first synchronization sequence to a first resource block of a synchronization channel associated with a first frequency sub-band of a shared radio frequency spectrum band and the second synchronization sequence to a second resource block associated with a second frequency sub-band of the synchronization channel; and

transmitting the first synchronization sequence and the second synchronization sequence concurrently over the synchronization channel using the first resource block and the second resource block according to the mapping.

2. The method of claim 1, wherein generating the second synchronization sequence comprises:

applying a first phase shift to the first synchronization sequence.

3. The method of claim 2, further comprising:

generating a third synchronization sequence by applying a second phase shift to the first synchronization sequence, the second phase shift being different from the first phase shift; and

mapping the third synchronization sequence to a third resource block of the synchronization channel.

4. The method of claim 3, further comprising:

transmitting the third synchronization sequence using the third resource block;

wherein transmitting the third synchronization sequence is concurrent with transmitting the first synchronization sequence and the second synchronization sequence.

5. The method of claim 3, wherein the second phase shift is a multiple of the first phase shift.

6. The method of claim 3, wherein the first phase shift is different than the second phase shift, and the second phase shift is based at least in part on a payload of a secondary synchronization signal (SSS).

7. The method of claim 3, wherein the first phase shift is same as the second phase shift.

8. The method of claim 2, wherein the first phase shift is based at least in part on a bandwidth of the shared radio frequency spectrum band.

9. The method of claim 1, wherein the first synchronization sequence comprises at least one of a primary synchronization signal (PSS), a secondary synchronization signal (SSS), a physical broadcast channel (PBCH), or combinations thereof.

10. The method of claim 9, further comprising:

generating the second synchronization sequence is further based at least in part on a content of the PSS, the SSS, or the PBCH.

11. A method for wireless communication, comprising:

receiving a first synchronization sequence over a synchronization channel using a first resource block associated with a first frequency sub-band of a shared radio frequency spectrum band;

receiving a second synchronization sequence over the synchronization channel using a second resource block associated with a second frequency sub-band of the shared radio frequency spectrum band, wherein the first resource block and the second resource block are concurrent in time;

obtaining system acquisition information for a base station based at least in part on a combination of the first synchronization sequence and the second synchronization sequence; and

establishing a connection with the base station using the obtained system acquisition information.

12. The method of claim 11, wherein obtaining the system acquisition information comprises:

applying a first phase shift to the second synchronization sequence to obtain a phase-shifted version of the second synchronization sequence;

wherein the combination of the first synchronization sequence and the second synchronization sequence comprises a sum of the first synchronization sequence and the phase-shifted version of the second synchronization sequence.

13. The method of claim 12, further comprising:

receiving a third synchronization sequence over the synchronization channel using a third resource block associated with a third sub-band of the shared radio frequency spectrum, wherein the first resource block, the second resource block, and the third resource block are concurrent in time; and

applying a second phase shift to the third synchronization sequence to obtain a phase-shifted version of the third synchronization sequence;

wherein the combination of the first synchronization sequence and the second synchronization sequence;

comprises a sum of the first synchronization sequence, the phase-shifted version of the second synchronization sequence, and the phase-shifted version of the third synchronization sequence.

14. The method of claim 13, wherein the second phase shift is a multiple of the first phase shift.

15. The method of claim 13, wherein the first phase shift is different than the second phase shift, and the second phase shift is based at least in part on a payload of the secondary synchronization signal (SSS).

16. The method of claim 12, wherein the first phase shift is based at least in part on a bandwidth of the shared radio frequency spectrum band.

17. The method of claim 11, wherein the first synchronization sequence comprises at least one of a primary synchronization signal (PSS), a secondary synchronization signal (SSS), a physical broadcast channel (PBCH), or combinations thereof.

18. The method of claim 17, wherein the second synchronization sequence is based at least in part on a content of the PSS, the SSS, or the PBCH.

19. The method of claim 18, wherein obtaining the system acquisition information for the base station comprises:

detecting a timing parameter based at least in part on the content of the PSS;

detecting an identification parameter based at least in part on a payload of the SSS;

determining a cell specific reference signal (CRS) sequence based at least in part on the timing parameter and the identification parameter; and

decoding the PBCH using the CRS sequence.

20. An apparatus for wireless communication, 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;

identify a first synchronization sequence;

generate a second synchronization sequence based at least in part on the first synchronization sequence;

map the first synchronization sequence to a first resource block of a synchronization channel associated with a first frequency sub-band of a shared radio frequency spectrum band and the second synchronization sequence to a second resource block associated with a second frequency sub-band of the synchronization channel; and

transmit the first synchronization sequence and the second synchronization sequence concurrently over the synchronization channel using the first resource block and the second resource block according to the mapping.

21. The apparatus of claim 20, wherein the instructions executable by the processor to generate the second synchronization sequence comprise instructions executable by the processor to:

apply a first phase shift to the first synchronization sequence.

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

generate a third synchronization sequence by applying a second phase shift to the first synchronization sequence, the second phase shift being different from the first phase shift; and

map the third synchronization sequence to a third resource block of the synchronization channel.

23. The apparatus of claim 22, wherein the instructions are further executable by the processor to:

transmit the third synchronization sequence using the third resource block; and

transmit the third synchronization sequence is concurrent with transmitting the first synchronization sequence and the second synchronization sequence.

24. The apparatus of claim 22, wherein the second phase shift is a multiple of the first phase shift.

25. The apparatus of claim 22, wherein the first phase shift is different than the second phase shift, and the second phase shift is based at least in part on a payload of a secondary synchronization signal (SSS).

26. The apparatus of claim 22, wherein the first phase shift is same as the second phase shift.

27. An apparatus for wireless communication, 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;

receive a first synchronization sequence over a synchronization channel using a first resource block associated with a first frequency sub-band of a shared radio frequency spectrum band;

receive a second synchronization sequence over the synchronization channel using a second resource block associated with a second frequency sub-band of the shared radio frequency spectrum band, wherein the first resource block and the second resource block are concurrent in time;

obtain system acquisition information for a base station based at least in part on a combination of the first synchronization sequence and the second synchronization sequence; and

establish a connection with the base station using the obtained system acquisition information.

28. The apparatus of claim 27, wherein the instructions executable by the processor to obtain the system acquisition information comprise instructions executable by the processor to:

apply a first phase shift to the second synchronization sequence to obtain a phase-shifted version of the second synchronization sequence;

wherein the combination of the first synchronization sequence and the second synchronization sequence comprises a sum of the first synchronization sequence and the phase-shifted version of the second synchronization sequence.

29. The apparatus of claim 28, wherein the instructions are further executable by the processor to:

receive a third synchronization sequence over the synchronization channel using a third resource block associated with a third sub-band of the shared radio frequency spectrum, wherein the first resource block, the second resource block, and the third resource block are concurrent in time; and

apply a second phase shift to the third synchronization sequence to obtain a phase-shifted version of the third synchronization sequence;

wherein the combination of the first synchronization sequence and the second synchronization sequence;

comprises a sum of the first synchronization sequence, the phase-shifted version of the second synchronization sequence, and the phase-shifted version of the third synchronization sequence.

30. The apparatus of claim 29, wherein the second phase shift is a multiple of the first phase shift.