UNLICENSED SPECTRUM COVERAGE ENHANCEMENT FOR INDUSTRIAL INTERNET OF THINGS

• US 20180123859A1
• Filed: 09/06/2017
• Published: 05/03/2018
• Est. Priority Date: 10/31/2016
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Liu, Chih-Hao, Patel, Chirag, Yerramalli, Srinivas, Kadous, Tamer
• Granted Patent: US 10,547,494 B2
• Time in Patent Office: Days
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/005 of common pilots, i.e. pilots destined for multiple users or terminals
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 67/1068 Discovery involving direct consultation or announcement among potential requesting and potential source peers
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes
• CPC Class Codes: H04L 69/323 in the physical layer [OSI layer 1]
• CPC Class Codes: H04L 69/324 in the data link layer [OSI layer 2], e.g. HDLC
• CPC Class Codes: H04W 4/70 Services for machine-to-machine communication [M2M] or machine type communication [MTC]
• CPC Class Codes: H04W 48/12 using downlink control channel

Abstract

This disclosure includes methods, systems, and devices for wireless communication. A repetition of symbols may be used to increase a device'"'"'s ability to synchronize and communicate using unlicensed spectrum. For example, a base station may schedule a frame that includes repetitions, in time or frequency, of a control or data signal. After performing a listen-before-talk (LBT) procedure, the base station may broadcast or transmit the frame to one or more devices, such as a user equipment (UE). For instance, the frame may include repetitions of a discovery reference signal (DRS), and be broadcast by the base station to enable synchronization by the UE. In other examples, the signal may include repetitions of a cell-specific reference signal (CRS), and a UE may identify a start of a transmission opportunity using the CRSs. Other signals, such as downlink control and shared channels, may be repeated within a frame in a similar manner.

Claims

1. A method for wireless communication at a device using unlicensed spectrum, comprising:

receiving a first frame including a first signal and at least one repetition of the first signal in time or in frequency, the first signal including a data signal or a control signal; and

communicating with a base station based at least in part on the received first frame.

2. The method of claim 1, wherein the first signal includes a discovery reference signal (DRS) within a temporally first subframe of the received first frame, and wherein the at least one repetition of the first signal includes a repetition of the DRS within one or more subsequent subframes of the received first frame, the method further comprising:

determining a timing synchronization, a system bandwidth, and system information block (SIB) information associated with the base station based at least in part on the DRS and the repetition of the DRS.

3. The method of claim 2, wherein the first signal includes a synchronization signal within a DRS subframe of the received first frame, and wherein the at least one repetition of the first signal includes a repetition of the synchronization signal within the DRS subframe.

4. The method of claim 2, wherein the first signal includes an enhanced machine type communication (MTC) physical downlink control channel (eMPDCCH) within a temporally second subframe of the received first frame, the method further comprising:

identifying a plurality of system information blocks (SIBs) within a subsequent subframe of the received first frame based at least in part on the eMPDCCH.

5. The method of claim 1, wherein the first signal includes a plurality of cell-specific reference signals (CRSs) within a temporally first subframe of the received first frame, and wherein the at least one repetition of the first signal includes a repetition of the CRSs over a plurality of subsequent subframes, the method further comprising:

detecting a start of a transmission opportunity based at least on a combination of the plurality of CRSs in the temporally first subframe.

6. The method of claim 1, wherein the first signal includes an enhanced machine type communication (MTC) physical downlink control channel (eMPDCCH) within a subframe of the received first frame, and wherein the at least one repetition of the first signal includes a frequency domain repetition of the eMPDCCH within a transmission opportunity as the subframe, the method further comprising:

identifying a starting point of the eMPDCCH based at least in part on the subframe; and

decoding the first frame based at least in part on the starting point of the eMPDCCH and an accumulation of the eMPDCCH within the transmission opportunity of the subframe.

7. The method of claim 1, wherein the first signal includes a physical downlink control channel (PDCCH) within a subframe of the received first frame, and wherein the at least one repetition of the first signal includes a repetition of the PDCCH within a same transmission opportunity as the subframe, the method further comprising:

identifying a starting point of the PDCCH based at least in part on the subframe; and

decoding the first frame based at least in part on the identified starting point of the PDCCH and an accumulation of the PDCCH within the same transmission opportunity of the subframe.

8. The method of claim 1, wherein the first signal includes a physical downlink control channel (PDCCH) within a temporally first subframe of the received first frame, and wherein the temporally first subframe is within a first transmission opportunity, and the at least one repetition of the first signal includes a repetition of the PDCCH within a subsequent transmission opportunity, the method further comprising:

identifying a starting point of the PDCCH based at least in part on the temporally first subframe; and

decoding the first frame based at least in part on the starting point of the PDCCH and an accumulation of the PDCCH within the first transmission opportunity and the subsequent transmission opportunity.

9. The method of claim 1, wherein the first signal includes a physical downlink shared channel (PDSCH) within a first subframe of the received first frame, and wherein the at least one repetition of the first signal includes a repetition of the PDSCH within additional subframes of a transmission opportunity including the first subframe, the method further comprising:

decoding the PDSCH based at least in part on the PDSCH within the first subframe and the repetition of the PDSCH within the additional subframes.

10. The method of claim 1, wherein the first signal includes a physical downlink shared channel (PDSCH) within a subframe of the received first frame, and wherein the at least one repetition of the first signal includes a time-domain repetition of the PDSCH within a transmission opportunity including the subframe and a subsequent transmission opportunity.

11. The method of claim 1, further comprising:

transmitting a second frame including a second signal and at least one repetition of the second signal, the second signal including a physical random access channel (PRACH), and wherein the second signal and the at least one repetition of the second signal are located within contiguous subframes.

12. The method of claim 1, wherein the first frame includes a semi-statically configured uplink-to-downlink ratio.

13. A method for wireless communication at a device using unlicensed spectrum, comprising:

generating a frame including a signal and at least one repetition of the signal in time or in frequency, the signal including a data signal or a control signal;

performing a listen before talk (LBT) procedure for one or more channels in the unlicensed spectrum;

determining that the one or more channels are clear based at least in part on the performed LBT procedure; and

transmitting the frame based at least in part on the determination.

14. The method of claim 13, wherein the signal includes a discovery reference signal (DRS) within a temporally first subframe of the frame, and wherein the at least one repetition of the signal includes a repetition of the DRS within one or more subsequent subframes of the frame.

15. The method of claim 14, wherein the signal includes a synchronization signal within a DRS subframe of the frame, and wherein the at least one repetition of the signal includes a repetition of the synchronization signal within the DRS subframe.

16. The method of claim 14, wherein the signal includes an enhanced machine type communication (MTC) physical downlink control channel (eMPDCCH) within a temporally second subframe of the frame.

17. The method of claim 13, wherein the signal includes a plurality of cell-specific reference signals (CRSs) within a temporally first subframe of the frame, and wherein the at least one repetition of the signal includes a repetition of the CRSs over a plurality of subsequent subframes.

18. The method of claim 13, wherein the signal includes an enhanced machine type communication (MTC) physical downlink control channel (eMPDCCH) within a subframe of the frame, and wherein the at least one repetition of the signal includes a frequency domain repetition of the eMPDCCH within a transmission opportunity as the subframe.

19. The method of claim 13, wherein the signal includes a physical downlink shared channel (PDSCH) within a first subframe of the frame, and wherein the at least one repetition of the signal includes a repetition of the PDSCH within additional subframes of a transmission opportunity including the first subframe.

20. The method of claim 13, wherein the signal includes a physical downlink shared channel (PDSCH) within a subframe of the frame, and wherein the at least one repetition of the signal includes a time-domain repetition of the PDSCH within a transmission opportunity including the subframe and a subsequent transmission opportunity.

21. An apparatus for wireless communication at a device using unlicensed spectrum, in a system comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to;

receive a first frame including a first signal and at least one repetition of the first signal in time or in frequency, the first signal including a data signal or a control signal; and

communicate with a base station based at least in part on the received first frame.

22. The apparatus of claim 21, wherein the first signal includes a discovery reference signal (DRS) within a temporally first subframe of the received first frame, and wherein the at least one repetition of the first signal includes a repetition of the DRS within one or more subsequent subframes of the received first frame, the instructions further executable to:

determine a timing synchronization, a system bandwidth, and system information block (SIB) information associated with the base station based at least in part on the DRS and the repetition of the DRS.

23. The apparatus of claim 22, wherein the first signal includes a synchronization signal within a DRS subframe of the received first frame, and wherein the at least one repetition of the first signal includes a repetition of the synchronization signal within the DRS subframe.

24. The apparatus of claim 22, wherein the first signal includes an enhanced machine type communication (MTC) physical downlink control channel (eMPDCCH) within a temporally second subframe of the received first frame, the instructions further executable to:

identify a plurality of SIBs within a subsequent subframe of the received first frame based at least in part on the eMPDCCH.

25. The apparatus of claim 21, wherein the first signal includes an enhanced machine type communication (MTC) physical downlink control channel (eMPDCCH) within a subframe of the received first frame, and wherein the at least one repetition of the first signal includes a frequency domain repetition of the eMPDCCH within a transmission opportunity as the subframe, the instructions further executable to:

identify a starting point of the eMPDCCH based at least in part on the subframe; and

decode the first frame based at least in part on the starting point of the eMPDCCH and an accumulation of the eMPDCCH within the transmission opportunity of the subframe.

26. The apparatus of claim 21, wherein the first signal includes a physical downlink shared channel (PDSCH) within a subframe of the received first frame, and wherein the at least one repetition of the first signal includes a time-domain repetition of the PDSCH within a transmission opportunity including the subframe and a subsequent transmission opportunity.

27. An apparatus for wireless communication at a device using unlicensed spectrum, in a system comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to;

generate a frame including a signal and at least one repetition of the signal in time or in frequency, the signal including a data signal or a control signal;

perform a listen before talk (LBT) procedure for one or more channels in the unlicensed spectrum;

determine that the one or more channels are clear based at least in part on the performed LBT procedure; and

transmit the frame based at least in part on the determination.

28. The apparatus of claim 27, wherein the signal includes a discovery reference signal (DRS) within a temporally first subframe of the frame, and wherein the at least one repetition of the signal includes a repetition of the DRS within one or more subsequent subframes of the frame.

29. The apparatus of claim 27, wherein the signal includes an enhanced machine type communication (MTC) physical downlink control channel (eMPDCCH) within a subframe of the frame, and wherein the at least one repetition of the signal includes a frequency domain repetition of the eMPDCCH within a transmission opportunity as the subframe.

30. The apparatus of claim 27, wherein the signal includes a physical downlink shared channel (PDSCH) within a subframe of the frame, and wherein the at least one repetition of the signal includes a time-domain repetition of the PDSCH within a transmission opportunity including the subframe and a subsequent transmission opportunity.