Narrowband time-division duplex frame structure for narrowband communications

• US 10,454,659 B2
• Filed: 09/20/2017
• Issued: 10/22/2019
• Est. Priority Date: 02/28/2017
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Bhattad, Kapil, Wang, Xiao feng, Rico Alvarino, Alberto, Xu, Hao
• Primary Examiner(s): Towfighi, Afshawn M
• Application Number:
  US15/710,748
• Publication Number:
  US 20180248675A1
• Time in Patent Office: 762 Days
• CPC Class Codes: H04L 1/0067 Rate matching H04L1/0013 and H04L1/08 take precedence
• CPC Class Codes: H04L 1/0068 by puncturing
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence
• CPC Class Codes: H04L 25/02 Details ; arrangements for supplying electrical power along data transmission lines systems for transmitting signals via power distribution lines H04B3/54
• CPC Class Codes: H04L 25/0226 sounding signals per se
• CPC Class Codes: H04L 27/261 Details of reference signals
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 5/0005 Time-frequency
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0012 Hopping in multicarrier systems for frequency hopping in spread spectrum systems H04B1/713
• CPC Class Codes: H04L 5/0026 Division using four or more dimensions
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• 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 5/0092 Indication of how the channel is divided
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex
• CPC Class Codes: H04L 5/1469 using time-sharing
• CPC Class Codes: H04L 5/22 using time-division multiplexing
• CPC Class Codes: H04L 5/26 combined with the use of different frequencies
• CPC Class Codes: H04W 72/0446 : Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/0453 : Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/0466 : the resource being a scrambling code
• CPC Class Codes: H04W 72/21 : in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/23 : in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 74/0833 : Random access procedures, e.g. with 4-step access

Abstract

There is a need to support narrowband TDD frame structure for narrowband communications. The present disclosure provides a solution by supporting one or more narrowband TDD frame structure(s) for narrowband communications. In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may receive information associated with a narrowband TDD frame structure for narrowband communications. The apparatus may transmit a first symbol group of a first narrowband physical random access channel (NPRACH) preamble to a base station. In one aspect, a first length of the first symbol group may be associated with the narrowband TDD frame structure.

Claims

1. A method for wireless communication for a user equipment (UE), comprising:

receiving information associated with a time-division duplex (TDD) frame structure for narrowband communications; and

transmitting a first symbol group of a first narrowband physical random access channel (NPRACH) preamble to a base station, a first length of the first symbol group being associated with the TDD frame structure;

wherein the first length of the first symbol group is shorter than a second length of a second symbol group of a second NPRACH preamble transmitted using a frequency-division duplex (FDD) frame structure.

2. The method of claim 1, wherein the first length of the first symbol group is selected such that N symbol groups can be transmitted on N subframes.

3. The method of claim 1, wherein the first length of the first symbol group is associated with one or more uplink durations of the TDD frame structure.

4. A method for wireless communication for a user equipment (UE), comprising:

receiving information associated with a time-division duplex (TDD) frame structure for narrowband communications; and

transmitting a first symbol group of a first narrowband physical random access channel (NPRACH) preamble to a base station, a first length of the first symbol group being associated with the TDD frame structure;

wherein the first length of the first symbol group is longer than a second length of a second symbol group of a second NPRACH preamble transmitted using a frequency-division duplex (FDD) frame structure.

5. A method for wireless communication for a user equipment (UE), comprising:

receiving information associated with a time-division duplex (TDD) frame structure for narrowband communications; and

transmitting a first symbol group of a first narrowband physical random access channel (NPRACH) preamble to a base station, a first length of the first symbol group being associated with the TDD frame structure;

wherein a first preamble format associated with the first NPRACH preamble is different than a second preamble format associated with a second NPRACH preamble transmitted using a frequency-division duplex (FDD) frame structure.

6. A method for wireless communication for a user equipment (UE), comprising:

receiving information associated with a time-division duplex (TDD) frame structure for narrowband communications;

determining a maximum number of symbol groups in a plurality of symbol groups associated with a narrowband physical random access channel (NPRACH) preamble that fit in an uplink occasion in the TDD frame structure; and

transmitting a first subset of the plurality of symbol groups associated with the NPRACH preamble in a first uplink occasion in the TDD frame structure and a second subset of the plurality of symbol groups associated with the NPRACH preamble in a second uplink occasion in the TDD frame structure,

wherein the first subset includes the maximum number of symbol groups, and

wherein the second subset includes any remaining symbol groups in the plurality of symbol groups or the maximum number of symbol groups.

7. The method of claim 6, wherein the plurality of symbol groups includes four symbol groups.

8. The method of claim 6, wherein a length of a symbol group is a function of the TDD frame structure.

9. A method for wireless communication for a user equipment (UE), comprising:

receiving information associated with a time-division duplex (TDD) frame structure for narrowband communications; and

determining a first number of symbol groups of a narrowband physical random access channel (NPRACH) preamble to transmit in a first uplink occasion in the TDD frame structure, the first number of symbol groups including either two symbol groups or three symbol groups.

10. The method of claim 9, wherein the first number of symbol groups includes the two symbol groups, the method further comprising:

transmitting a first symbol group of the two symbol groups in a first tone in the first uplink occasion and a second symbol group of the two symbol groups in a second tone in the first uplink occasion, a distance between the first tone and the second tone being either one tone or six tones.

11. The method of claim 9, wherein the first number of symbol groups includes the three symbol groups, the method further comprising:

transmitting a first symbol group of the three symbol groups in a first tone of the first uplink occasion, a second symbol group of the three symbol groups in a second tone of the first uplink occasion, and a third symbol group of the three symbol groups in a third tone of the first uplink occasion, a first distance between tones used for at least one pair of the symbol groups is one tone, and a second distance between tones used for another pair of the symbol groups is six tones.

12. The method of claim 11, further comprising:

transmitting a fourth symbol group in a fourth tone in a second uplink occasion subsequent to the first uplink occasion, a third distance between the third tone and the fourth tone being one tone.

13. A method for wireless communication for a user equipment (UE), comprising:

receiving information associated with a time-division duplex (TDD) frame structure for narrowband communications;

determining a hopping pattern associated with two pairs of symbol groups of a narrowband physical random access channel (NPRACH) transmitted in one or more uplink occasions using the TDD frame structure; and

transmitting a first pair of symbol groups and a second pair of symbol groups in a same uplink occasion or in adjacent uplink occasions in the TDD frame structure,

wherein a first subcarrier spacing associated with the first pair of symbol groups is a single subcarrier, and

wherein a second subcarrier spacing associated with the second pair of symbol groups is six subcarriers.

14. An apparatus for wireless communication for a user equipment (UE), comprising:

means for receiving information associated with a time-division duplex (TDD) frame structure for narrowband communications; and

means for transmitting a first symbol group of a first narrowband physical random access channel (NPRACH) preamble to a base station, a first length of the first symbol group being associated with the TDD frame structure;

wherein the first length of the first symbol group is shorter than a second length of a second symbol group of a second NPRACH preamble transmitted using a frequency-division duplex (FDD) frame structure.

15. The apparatus of claim 14, wherein the first length of the first symbol group is selected such that N symbol groups can be transmitted on N subframes.

16. The apparatus of claim 14, wherein the first length of the first symbol group is associated with one or more uplink durations of the TDD frame structure.

17. An apparatus for wireless communication for a user equipment (UE), comprising:

means for receiving information associated with a time-division duplex (TDD) frame structure for narrowband communications; and

means for transmitting a first symbol group of a first narrowband physical random access channel (NPRACH) preamble to a base station, a first length of the first symbol group being associated with the TDD frame structure;

wherein the first length of the first symbol group is longer than a second length of a second symbol group of a second NPRACH preamble transmitted using a frequency-division duplex (FDD) frame structure.

18. An apparatus for wireless communication for a user equipment (UE), comprising:

means for receiving information associated with a time-division duplex (TDD) frame structure for narrowband communications; and

means for transmitting a first symbol group of a first narrowband physical random access channel (NPRACH) preamble to a base station, a first length of the first symbol group being associated with the TDD frame structure;

wherein a first preamble format associated with the first NPRACH preamble is different than a second preamble format associated with a second NPRACH preamble transmitted using a frequency-division duplex (FDD) frame structure.

19. An apparatus for wireless communication for a user equipment (UE), comprising:

means for receiving information associated with a time-division duplex (TDD) frame structure for narrowband communications;

means for determining a maximum number of symbol groups in a plurality of symbol groups associated with a physical random access channel (NPRACH) preamble that fit in an uplink occasion in the TDD frame structure; and

means for transmitting a first subset of the plurality of symbol groups associated with the NPRACH preamble in a first uplink occasion in the TDD frame structure and a second subset of the plurality of symbol groups associated with the NPRACH preamble in a second uplink occasion in the TDD frame structure,

wherein the first subset includes the maximum number of symbol groups, and

wherein the second subset includes any remaining symbol groups in the plurality of symbol groups or the maximum number of symbol groups.

20. The apparatus of claim 19, wherein the plurality of symbol groups includes four symbol groups.

21. The apparatus of claim 19, wherein a length of a symbol group is a function of the TDD frame structure.

22. An apparatus for wireless communication for a user equipment (UE), comprising:

means for receiving information associated with a time-division duplex (TDD) frame structure for narrowband communications; and

means for determining a first number of symbol groups of a narrowband physical random access channel (NPRACH) preamble to transmit in a first uplink occasion in the TDD frame structure, the first number of symbol groups including either two symbol groups or three symbol groups.

23. The apparatus of claim 22, wherein the first number of symbol groups includes the two symbol groups, the method further comprising:

means for transmitting a first symbol group of the two symbol groups in a first tone in the first uplink occasion and a second symbol group of the two symbol groups in a second tone in the first uplink occasion, a distance between the first tone and the second tone being either one tone or six tones.

24. The apparatus of claim 22, wherein the first number of symbol groups includes the three symbol groups, the method further comprising:

means for transmitting a first symbol group of the three symbol groups in a first tone of the first uplink occasion, a second symbol group of the three symbol groups in a second tone of the first uplink occasion, and a third symbol group of the three symbol groups in a third tone of the first uplink occasion, a first distance between tones used for at least one pair of the symbol groups is one tone, and a second distance between tones used for another pair of the symbol groups is six tone.

25. The apparatus of claim 24, further comprising:

means for transmitting a fourth symbol group in a fourth tone in a second uplink occasion subsequent to the first uplink occasion, a third distance between the third tone and the fourth tone being one tone.

26. An apparatus for wireless communication for a user equipment (UE), comprising:

means for receiving information associated with a time-division duplex (TDD) frame structure for narrowband communications;

means for determining a hopping pattern associated with two pairs of symbol groups of a narrowband physical random access channel (NPRACH) transmitted in one or more uplink occasions using the TDD frame structure; and

means for transmitting a first pair of symbol groups and a second pair of symbol groups in a same uplink occasion or in adjacent uplink occasions in the TDD frame structure,

wherein a first subcarrier spacing associated with the first pair of symbol groups is a single subcarrier, and

wherein a second subcarrier spacing associated with the second pair of symbol groups is six subcarriers.

27. An apparatus for wireless communication for a user equipment (UE), comprising:

a memory; and

at least one processor coupled to the memory and configured to;

receive information associated with a time-division duplex (TDD) frame structure for narrowband communications; and

transmit a first symbol group of a first narrowband physical random access channel (NPRACH) preamble to a base station, a first length of the first symbol group being associated with the TDD frame structure;

wherein the first length of the first symbol group is shorter than a second length of a second symbol group of a second NPRACH preamble transmitted using a frequency-division duplex (FDD) frame structure.

28. The apparatus of claim 27, wherein the first length of the first symbol group is selected such that N symbol groups can be transmitted on N subframes.

29. The apparatus of claim 27, wherein the first length of the first symbol group is associated with one or more uplink durations of the TDD frame structure.

30. An apparatus for wireless communication for a user equipment (UE), comprising:

a memory; and

at least one processor coupled to the memory and configured to;

receive information associated with a time-division duplex (TDD) frame structure for narrowband communications; and

transmit a first symbol group of a first narrowband physical random access channel (NPRACH) preamble to a base station, a first length of the first symbol group being associated with the TDD frame structure;

wherein the first length of the first symbol group is longer than a second length of a second symbol group of a second NPRACH preamble transmitted using a frequency-division duplex (FDD) frame structure.

31. An apparatus for wireless communication for a user equipment (UE), comprising:

a memory; and

at least one processor coupled to the memory and configured to;

receive information associated with a time-division duplex (TDD) frame structure for narrowband communications; and

transmit a first symbol group of a first narrowband physical random access channel (NPRACH) preamble to a base station, a first length of the first symbol group being associated with the TDD frame structure;

wherein a first preamble format associated with the first NPRACH preamble is different than a second preamble format associated with a second NPRACH preamble transmitted using a frequency-division duplex (FDD) frame structure.

32. An apparatus for wireless communication for a user equipment (UE), comprising:

a memory; and

at least one processor coupled to the memory and configured to;

receive information associated with a time-division duplex (TDD) frame structure for narrowband communications;

determine a maximum number of symbol groups in a plurality of symbol groups associated with a narrowband physical random access channel (NPRACH) preamble that fit in an uplink occasion in the TDD frame structure; and

transmit a first subset of the plurality of symbol groups associated with the NPRACH preamble in a first uplink occasion in the TDD frame structure and a second subset of the plurality of symbol groups associated with the NPRACH preamble in a second uplink occasion in the TDD frame structure,

wherein the first subset includes the maximum number of symbol groups, and

wherein the second subset includes any remaining symbol groups in the plurality of symbol groups or the maximum number of symbol groups.

33. The apparatus of claim 32, wherein the plurality of symbol groups includes four symbol groups.

34. The apparatus of claim 32, wherein a length of a symbol group is a function of the TDD frame structure.

35. An apparatus for wireless communication for a user equipment (UE), comprising:

a memory; and

at least one processor coupled to the memory and configured to;

receive information associated with a time-division duplex (TDD) frame structure for communications; and

determine a first number of symbol groups of a narrowband physical random access channel (NPRACH) preamble to transmit in a first uplink occasion in the TDD frame structure, the first number of symbol groups including either two symbol groups or three symbol groups.

36. The apparatus of claim 35, wherein the first number of symbol groups includes the two symbol groups, the at least one processor is further configured to:

transmit a first symbol group of the two symbol groups in a first tone in the first uplink occasion and a second symbol group of the two symbol groups in a second tone in the first uplink occasion, a distance between the first tone and the second tone being either one tone or six tones.

37. The apparatus of claim 35, wherein the first number of symbol groups includes the three symbol groups, the at least one processor is further configured to:

transmit a first symbol group of the three symbol groups in a first tone of the first uplink occasion, a second symbol group of the three symbol groups in a second tone of the first uplink occasion, and a third symbol group of the three symbol groups in a third tone of the first uplink occasion, a first distance between tones used for at least one pair of the symbol groups is one tone, and a second distance between tones used for another pair of the symbol groups is six tones.

38. The apparatus of claim 37, wherein the at least one processor is further configured to:

transmit a fourth symbol group in a fourth tone in a second uplink occasion subsequent to the first uplink occasion, a third distance between the third tone and the fourth tone being one tone.

39. An apparatus for wireless communication for a user equipment (UE), comprising:

a memory; and

at least one processor coupled to the memory and configured to;

receive information associated with a time-division duplex (TDD) frame structure for narrowband communications;

determine a hopping pattern associated with two pairs of symbol groups of a narrowband physical random access channel (NPRACH) transmitted in one or more uplink occasions using the TDD frame structure; and

transmit a first pair of symbol groups and a second pair of symbol groups in a same uplink occasion or in adjacent uplink occasions in the TDD frame structure,

wherein a first subcarrier spacing associated with the first pair of symbol groups is a single subcarrier, and

wherein a second subcarrier spacing associated with the second pair of symbol groups is six subcarriers.

40. A non-transitory computer-readable medium storing computer executable code for a user equipment (UE), comprising code to:

receive information associated with a time-division duplex (TDD) frame structure for narrowband communications; and

transmit a first symbol group of a first narrowband physical random access channel (NPRACH) preamble to a base station, a first length of the first symbol group being associated with the TDD frame structure;

wherein the first length of the first symbol group is shorter than a second length of a second symbol group of a second NPRACH preamble transmitted using a frequency-division duplex (FDD) frame structure.

41. The non-transitory computer-readable medium of claim 40, wherein the first length of the first symbol group is selected such that N symbol groups can be transmitted on N subframes.

42. The non-transitory computer-readable medium of claim 40, wherein the first length of the first symbol group is associated with one or more uplink durations of the TDD frame structure.

43. A non-transitory computer-readable medium storing computer executable code for a user equipment (UE), comprising code to:

receive information associated with a time-division duplex (TDD) frame structure for narrowband communications; and

transmit a first symbol group of a first narrowband physical random access channel (NPRACH) preamble to a base station, a first length of the first symbol group being associated with the TDD frame structure;

wherein the first length of the first symbol group is longer than a second length of a second symbol group of a second NPRACH preamble transmitted using a frequency-division duplex (FDD) frame structure.

44. A non-transitory computer-readable medium storing computer executable code for a user equipment (UE), comprising code to:

receive information associated with a time-division duplex (TDD) frame structure for narrowband communications; and

transmit a first symbol group of a first narrowband physical random access channel (NPRACH) preamble to a base station, a first length of the first symbol group being associated with the TDD frame structure;

wherein a first preamble format associated with the first NPRACH preamble is different than a second preamble format associated with a second NPRACH preamble transmitted using a frequency-division duplex (FDD) frame structure.

45. A non-transitory computer-readable medium storing computer executable code for a user equipment (UE), comprising code to:

receive information associated with a time-division duplex (TDD) frame structure for narrowband communications;

determine a maximum number of symbol groups in a plurality of symbol groups associated with a narrowband physical random access channel (NPRACH) preamble that fit in an uplink occasion in the TDD frame structure; and

transmit a first subset of the plurality of symbol groups associated with the NPRACH preamble in a first uplink occasion in the TDD frame structure and a second subset of the plurality of symbol groups associated with the NPRACH preamble in a second uplink occasion in the TDD frame structure,

wherein the first subset includes the maximum number of symbol groups, and

wherein the second subset includes any remaining symbol groups in the plurality of symbol groups or the maximum number of symbol groups.

46. The non-transitory computer-readable medium of claim 45, wherein the plurality of symbol groups includes four symbol groups.

47. The non-transitory computer-readable medium of claim 45, wherein a length of a symbol group is a function of the TDD frame structure.

48. A non-transitory computer-readable medium storing computer executable code for a user equipment (UE), comprising code to:

receive information associated with a time-division duplex (TDD) frame structure for narrowband communications; and

determine a first number of symbol groups of a narrowband physical random access channel (NPRACH) preamble to transmit in a first uplink occasion in the TDD frame structure, the first number of symbol groups including either two symbol groups or three symbol groups.

49. The non-transitory computer-readable medium of claim 48, wherein the first number of symbol groups includes the two symbol groups, and wherein the code is further configured to:

transmit a first symbol group of the two symbol groups in a first tone in the first uplink occasion and a second symbol group of the two symbol groups in a second tone in the first uplink occasion, a distance between the first tone and the second tone being either one tone or six tones.

50. The non-transitory computer-readable medium of claim 48, wherein the first number of symbol groups includes the three symbol groups, wherein the code is further configured to:

transmit a first symbol group of the three symbol groups in a first tone of the first uplink occasion, a second symbol group of the three symbol groups in a second tone of the first uplink occasion, and a third symbol group of the three symbol groups in a third tone of the first uplink occasion, a first distance between tones used for at least one pair of the symbol groups is one tone, and a second distance between tones used for another pair of the symbol groups is six tones.

51. The non-transitory computer-readable medium of claim 50, wherein the code is further configured to:

transmit a fourth symbol group in a fourth tone in a second uplink occasion subsequent to the first uplink occasion, a third distance between the third tone and the fourth tone being one tone.

52. A non-transitory computer-readable medium storing computer executable code for a user equipment (UE), comprising code to:

receive information associated with a time-division duplex (TDD) frame structure for narrowband communications;

determine a hopping pattern associated with two pairs of symbol groups of a narrowband physical random access channel (NPRACH) transmitted in one or more uplink occasions using the TDD frame structure; and

transmit a first pair of symbol groups and a second pair of symbol groups in a same uplink occasion or in adjacent uplink occasions in the TDD frame structure,

wherein a first subcarrier spacing associated with the first pair of symbol groups is a single subcarrier, and

wherein a second subcarrier spacing associated with the second pair of symbol groups is six subcarriers.