Signal sending or receiving method and device

A signal receiving method, comprising:

• receiving, by a receiving device, signals from 2M subcarriers, wherein the 2M subcarriers are subcarriers on a same time domain symbol;
• performing, by the receiving device, a fast Fourier transform (FFT) on the signals to obtain a first sequence and a second sequence, wherein the first sequence is carried on M even-numbered subcarriers in the 2M subcarriers, the second sequence is carried on M odd-numbered subcarriers in the 2M subcarriers, the first sequence is one of the third sequence and the fourth sequence, the second sequence is the other of the third sequence and the fourth sequence, and the fourth sequence is a sequence carrying M first information elements;
• and
• performing, by the receiving device, signal processing on a receive signal on M subcarriers that carry the fourth sequence, to obtain the M first information elements, wherein for elements of a first time domain sequence corresponding to the third sequence and a second time domain sequence corresponding to the fourth sequence at a same moment, when a complex factor is taken out, one of the first time domain sequence and the second time domain sequence is an in-phase component, and the other is a quadrature component.

A signal sending device, comprising:

• a processor configured to:
• map a first sequence onto M even-numbered subcarriers in 2M subcarriers, and map a second sequence onto M odd-numbered subcarriers in the 2M subcarriers, wherein the first sequence is one of a third sequence and a fourth sequence, the second sequence is the other of the third sequence and the fourth sequence, the 2M subcarriers are subcarriers on a same time domain symbol, the fourth sequence is a sequence carrying M first information elements, and for elements of a second time domain sequence corresponding to the fourth sequence and a first time domain sequence corresponding to the third sequence at a same moment, when a complex factor is taken out, one of the first time domain sequence and the second time domain sequence is an in-phase component, and the other is a quadrature component, and
• transform sequences mapped onto the 2M subcarriers to a time domain to generate transmit signals;
• and
• a transmitter configured to send the transmit signals generated by the processor.

A signal receiving device, comprising:

• a receiver configured to receive signals from 2M subcarriers, wherein the 2M subcarriers are subcarriers on a same time domain symbol;
• and
• a processor configured to:
• perform a fast Fourier transform (FFT) on the signals received by the receiver, to obtain a first sequence and a second sequence that are received, wherein the first sequence is carried on M even-numbered subcarriers in the 2M subcarriers, the second sequence is carried on M odd-numbered subcarriers in the 2M subcarriers, the first sequence is one of the third sequence and the fourth sequence, the second sequence is the other of the third sequence and the fourth sequence, and the fourth sequence is a sequence carrying M first information elements, and
• perform signal processing on a receive signal on M subcarriers that carry the fourth sequence, to obtain the M first information elements, wherein for elements of a first time domain sequence corresponding to the third sequence and a second time domain sequence corresponding to the fourth sequence at a same moment, when a complex factor is taken out, one of the first time domain sequence and the second time domain sequence is an in-phase component, and the other is a quadrature component.