Signal transmission method and apparatus

Patent metadata

Field	Value
Publication number	US-11902073-B2
Application number	US-202217986406-A
Country	US
Kind code	B2
Filing date	Nov 14, 2022
Priority date	May 15, 2020
Publication date	Feb 13, 2024
Grant date	Feb 13, 2024

Abstract

This application provides a signal transmission method and apparatus. The method includes: obtaining, by a transmitter side, a first signal with N points; performing signal separation on the first signal with N points, to obtain two groups of signals (for example, a second signal with N points and a third signal with N points); combining the two groups of signals obtained through separation, to obtain a to-be-sent signal with 3N/2 points; and sending the signal with 3N/2 points to a receiver side, to enable the receiver to restore the first signal with N points from the received signal with 3N/2 points.

First claim

What is claimed is:

1. A method, comprising:
obtaining a first signal with N points, wherein N is a positive even number;
determining a second signal with N points and a third signal with N points based on the first signal, wherein a fourth signal with N/2 points and a fifth signal with N/2 points are determined based on the second signal, and wherein a sixth signal with N/2 points and a seventh signal with N/2 points are determined based on the third signal;
determining an eighth signal with 3N/2 points based on the fourth signal, the fifth signal, the sixth signal, and the seventh signal, wherein the eighth signal is an orthogonal frequency division multiplexing (OFDM) signal to be carried in an optical signal; and
sending the eighth signal in the optical signal,
wherein the second signal is obtained by setting a signal at an even location in the first signal to 0 , and wherein the third signal is obtained by setting another signal at an odd location in the first signal to 0 .

2. The method according to claim 1 , further comprising:
performing inverse fast Fourier transform (IFFT) or fast Fourier transform FFT on the second signal to obtain a ninth signal with N points,
wherein the fourth signal is obtained by:
setting negative parts of first N/2 points of the ninth signal to 0 , or
setting positive parts of last N/2 points of the ninth signal to 0 and calculating an absolute value of negative parts of the last N/2 points of the ninth signal, and

wherein the fifth signal is obtained by:
setting positive parts of the first N/2 points of the ninth signal to 0 and calculating an absolute value of the negative parts of the first N/2 points of the ninth signal, or
setting negative parts of the last N/2 points of the ninth signal to 0 .

3. The method according to claim 1 , further comprising:
performing IFFT or FFT on the third signal to obtain a tenth signal with N points,
wherein the sixth signal is obtained by setting negative parts of first N/2 points or last N/2 points of the tenth signal to 0 , and
wherein the seventh signal is obtained by setting positive parts of the first N/2 points or the last N/2 points of the tenth signal to 0 and calculating an absolute value of the negative parts of the first N/2 points or the last N/2 points of the tenth signal.

4. The method according to claim 1 ,
wherein the eighth signal comprises either an eleventh signal with N/2 points or a twelfth signal with N/2 points, a thirteenth signal with N/2 points, and a fourteenth signal with N/2 points, or the eighth signal comprises either the thirteenth signal or the fourteenth signal, the eleventh signal, and the twelfth signal,
wherein the eleventh signal is determined based on the fourth signal and the sixth signal,
wherein the twelfth signal is determined based on the fourth signal and the seventh signal,
wherein the thirteenth signal is determined based on the fifth signal and the sixth signal, and
wherein the fourteenth signal is determined based on the fifth signal and the seventh signal.

5. The method according to claim 4 ,
wherein determining the eleventh signal based on the fourth signal and the sixth signal comprises:
summing up a fifteenth signal at a first location corresponding to the fourth signal and a sixteenth signal at a second location corresponding to the sixth signal to obtain a seventeenth signal with N/2 points comprised in the eleventh signal with N/2 points,

wherein determining the twelfth signal based on the fourth signal and the seventh signal comprises:
summing up the fifteenth signal at the first location corresponding to the fourth signal and an eighteenth signal at a third location corresponding to the seventh signal to obtain a nineteenth signal with N/2 points comprised in the twelfth signal,

wherein determining the thirteenth signal based on the fifth signal and the sixth signal comprises:
summing up a twentieth signal at a fourth location corresponding to the fifth signal and the sixteenth signal at the second location corresponding to the sixth signal to obtain a twenty-first signal with N/2 points comprised in the thirteenth signal, and

wherein determining the fourteenth signal based on the fifth signal and the seventh signal comprises:
summing up a twenty-second signal at the fourth location corresponding to the fifth signal and the seventeenth signal at the third location corresponding to the seventh signal to obtain a twenty-third signal with N/2 points comprised in the fourteenth signal.

6. A method, comprising:
obtaining an eighth signal with 3N/2 points, wherein the eighth signal is an orthogonal frequency division multiplexing (OFDM) signal carried in an optical signal, and wherein the eighth signal comprises three signals of an eleventh signal with N/2 points, a twelfth signal with N/2 points, a thirteenth signal with N/2 points, or a fourteenth signal with N/2 points;
determining a signal from the eleventh signal, the twelfth signal, the thirteenth signal, and the fourteenth signal other than the three signals comprised in the eighth signal; and
determining a first signal with N points based on the eleventh signal, the twelfth signal, the thirteenth signal, and the fourteenth signal,
wherein N is a positive even number.

7. The method according to claim 6 , wherein the determining the first signal based on the eleventh signal, the twelfth signal, the thirteenth signal, and the fourteenth signal comprises:
determining a fifteenth signal with N points based on the eleventh signal, the twelfth signal, the thirteenth signal, and the fourteenth signal; and
performing IFFT or FFT on the fifteenth signal to obtain the first signal with N points.

8. The method according to claim 7 , wherein the determining the fifteenth signal based on the eleventh signal, the twelfth signal, the thirteenth signal, and the fourteenth signal comprises:
determining a sixteenth signal with first N/2 points of the fifteenth signal based on a first difference between a seventeenth signal at a first location corresponding to the eleventh signal and a eighteenth signal at a second location corresponding to the fourteenth signal; and
determining a nineteenth signal with last N/2 points of the fifteenth signal based on a second difference between a twentieth signal at a third location corresponding to the thirteenth signal and a twenty-first signal at a fourth location corresponding to the twelfth signal.

9. The method according to claim 8 ,
wherein the eighth signal comprises either the eleventh signal or the twelfth signal, the thirteenth signal, and the fourteenth signal, or the eighth signal comprises either the thirteenth signal or the fourteenth signal, the eleventh signal, and the twelfth signal,
wherein the eleventh signal is obtained by:
summing up a twenty-second signal at a fifth location corresponding to a fourth signal with N/2 points and a twenty-third signal at a sixth location corresponding to a sixth signal with N/2 points,

wherein the twelfth signal is obtained by:
summing up the twenty-second signal at the fifth location corresponding to the fourth signal and a twenty-fourth signal at a seventh location corresponding to a seventh signal with N/2 points,

wherein the thirteenth signal is obtained by:
summing up a twenty-fifth signal at an eighth location corresponding to a fifth signal with N/2 points and the twenty-third signal at the sixth location corresponding to the sixth signal, and

wherein the fourteenth signal with N/2 points is obtained by:
summing up the twenty-fifth signal at the eighth location corresponding to the fifth signal and the twenty-fourth signal at the seventh location corresponding to the seventh signal.

Assignees

• Huawei Tech Co Ltd

Inventors

• Li Xu
• Huang Jingjing
• Zhang Junping

Classifications

• H04L27/2628 Primary

  Inverse Fourier transform modulators, e.g. inverse fast Fourier transform [IFFT] or inverse discrete Fourier transform [IDFT] modulators (H04L27/2634 takes precedence) · CPC title

• H04L5/0048

  Allocation of pilot signals, i.e. of signals known to the receiver (allocation of control signalling H04L5/0053; use of control signalling H04L5/0091) · CPC title

• H04L27/2634

  Inverse fast Fourier transform [IFFT] or inverse discrete Fourier transform [IDFT] modulators in combination with other circuits for modulation · CPC title

• H04B10/116 Primary

  Visible light communication · CPC title

• H04L27/2697 Primary

  in combination with other modulation techniques · CPC title