System and scheme of scalable OFDM numerology

Patent metadata

Field	Value
Publication number	US-10680864-B2
Application number	US-201816234129-A
Country	US
Kind code	B2
Filing date	Dec 27, 2018
Priority date	Jun 1, 2015
Publication date	Jun 9, 2020
Grant date	Jun 9, 2020

Abstract

For a wireless communications system, scalable orthogonal frequency division multiplexing (OFDM) numerology is incorporated in a manner that can apply to radio link transmissions in future wireless network for frequency division duplex (FDD) and time division duplex (TDD) communications.

First claim

What is claimed is:

1. A method comprising:
receiving, by a user equipment (UE), an indication of a first subcarrier spacing; and
transmitting or receiving, by the UE, an orthogonal frequency division multiplexing (OFDM) signal according to the first subcarrier spacing associated with a first transmission time unit (TTU),
wherein the first TTU comprises a fixed additional cyclic prefix (CP) duration and a first number of consecutive scalable symbol durations of the first subcarrier spacing, each scalable symbol duration of the first subcarrier spacing having a same time length and each comprising a first cyclic prefix (CP) part and a first useful OFDM signal part,
wherein the first subcarrier spacing is a 2 n multiple of a base subcarrier spacing, where n is a non-zero integer and the base subcarrier spacing is associated with a second TTU, the second TTU having a same time length as the first TTU and the second TTU comprising the fixed additional CP duration and a second number of consecutive scalable symbol durations of the base subcarrier spacing, each scalable symbol duration of the base subcarrier spacing having a same time length and each comprising a second CP part and a second useful OFDM signal part,
wherein a time length of the second CP part is the 2 n multiple of a time length of the first CP part and a time length of the second useful OFDM signal part is the 2 n multiple of a time length of the first useful OFDM signal part.

2. The method of claim 1 , wherein the base subcarrier spacing is 15 kHz and is associated with a long CP duration and a short CP duration, where a time length of the fixed additional CP duration is the difference between the long CP duration and the short CP duration.

3. The method of claim 1 , wherein the first subcarrier spacing is 15 kHz and is associated with a long CP duration and a short CP duration, where a time length of the fixed additional CP duration is the difference between the long CP duration and the short CP duration.

4. The method of claim 1 , wherein the first TTU comprises a starting symbol duration of the first subcarrier spacing, the starting symbol duration of the first subcarrier spacing comprising the fixed additional CP duration and a first scalable symbol duration of the first number of consecutive scalable symbol durations of the first subcarrier spacing, wherein the second TTU comprises a starting symbol duration of the base subcarrier spacing, the starting symbol duration of the base subcarrier spacing comprising the fixed additional CP duration and a second scalable symbol duration of the second number of consecutive scalable symbol durations of the base subcarrier spacing, and wherein the starting symbol duration of the first subcarrier spacing is not scaled with the starting symbol duration of the base subcarrier spacing.

5. The method of claim 1 , wherein the fixed additional CP duration is equal to a time length of 16 samples based on a sampling frequency of 30.72 MHz.

6. The method of claim 1 , wherein the fixed additional CP duration is at the start of the first TTU and at the start of the second TTU, and the start of the first TTU and the start of the second TTU are aligned in time domain, and the end of the first TTU and the end of the second TTU are aligned in the time domain.

7. The method of claim 6 , wherein a first frequency sub-band is associated with the first TTU and a second frequency sub-band is associated with the second TTU.

8. The method of claim 1 , wherein the first subcarrier spacing is 30 kHz, a time length of the first TTU is 0.5 ms, and the first TTU comprises the fixed additional CP duration and fourteen consecutive scalable symbol durations of the first subcarrier spacing.

9. The method of claim 1 , wherein the first subcarrier spacing is 60 kHz, a time length of the first TTU is 0.5 ms, and the first TTU comprises the fixed additional CP duration and twenty-eight consecutive scalable symbol durations of the first subcarrier spacing.

10. The method of claim 1 , wherein the base subcarrier spacing is 15 kHz, a time length of the second TTU is 0.5 ms, and the second TTU comprises the fixed additional CP duration and seven consecutive scalable symbol durations of the base subcarrier spacing.

11. A user equipment comprising:
a memory storing instructions; and
a processor configured, by the instructions, to:
receive an indication of a first subcarrier spacing; and
transmit or receiving an orthogonal frequency division multiplexing (OFDM) signal according to the first subcarrier spacing associated with a first transmission time unit (TTU),
wherein the first TTU comprises a fixed additional cyclic prefix (CP) duration and a first number of consecutive scalable symbol durations of the first subcarrier spacing, each scalable symbol duration of the first subcarrier spacing having a same time length and each comprising a first cyclic prefix (CP) part and a first useful OFDM signal part,
wherein the first subcarrier spacing is a 2 n multiple of a base subcarrier spacing, where n is a non-zero integer and the base subcarrier spacing is associated with a second TTU, the second TTU having a same time length as the first TTU and the second TTU comprising the fixed additional CP duration and a second number of consecutive scalable symbol durations of the base subcarrier spacing, each scalable symbol duration of the base subcarrier spacing having a same time length and each comprising a second CP part and a second useful OFDM signal part,
wherein a time length of the second CP part is the 2 n multiple of a time length of the first CP part and a time length of the second useful OFDM signal part is the 2 n multiple of a time length of the first useful OFDM signal part.

12. The user equipment of claim 11 , wherein the base subcarrier spacing is 15 kHz and is associated with a long CP duration and a short CP duration, where a time length of the fixed additional CP duration is the difference between the long CP duration and the short CP duration.

13. The user equipment of claim 11 , wherein the first subcarrier spacing is 15 kHz and is associated with a long CP duration and a short CP duration, where a time length of the fixed additional CP duration is the difference between the long CP duration and the short CP duration.

14. The user equipment of claim 11 , wherein the first TTU comprises a starting symbol duration of the first subcarrier spacing, the starting symbol duration of the first subcarrier spacing comprising the fixed additional CP duration and a first scalable symbol duration of the first number of consecutive scalable symbol durations of the first subcarrier spacing, wherein the second TTU comprises a starting symbol duration of the base subcarrier spacing, the starting symbol duration of the base subcarrier spacing comprising the fixed additional CP duration and a second scalable symbol duration of the second number of consecutive scalable symbol durations of the base subcarrier spacing, and wherein the starting symbol duration of the first subcarrier spacing is not scaled with the starting symbol duration of the base subcarrier spacing.

15. The user equipment of claim 11 , wherein the fixed additional CP duration is equal to a time length of 16 samples based on a sampling frequency of 30.72 MHz.

16. The user equipment of claim 11 , wherein the fixed additional CP duration is at the start of the first TTU and at the start of the second TTU, and the start of the first TTU and the start of the second TTU are aligned in time domain, and the end of the first TTU and the end of the second TTU are aligned in the time

Assignees

• Zhang Liqing
• Au Kelvin Kar Kin
• Ma Jianglei
• Tong Wen
• Islam Toufiqul
• Huawei Tech Co Ltd

Inventors

• Zhang Liqing
• Au Kelvin Kar Kin
• Ma Jianglei
• Tong Wen
• Islam Toufiqul

Classifications

• H04L27/2646

  using feedback from receiver for adjusting OFDM transmission parameters, e.g. transmission timing or guard interval length · CPC title

• H04L5/0007 Primary

  the frequencies being orthogonal, e.g. OFDM(A) or DMT · CPC title

• H04L27/2602 Primary

  Signal structure · CPC title

• H04W72/23

  in the downlink direction of a wireless link, i.e. towards a terminal · CPC title

• H04L27/26025

  Numerology, i.e. varying one or more of symbol duration, subcarrier spacing, Fourier transform size, sampling rate or down-clocking (allocating sub-channels of the transmission path H04L5/003) · CPC title