Method for Sending and Receiving Signal, and Corresponding Device and System

A system, comprising:

• a transmitter, comprising a processor and an analog-to-digital converter;
• and
• a receiver;
• wherein the processor is configured to:
• perform constellation mapping on a data stream to obtain a mapped signal;
• perform pre-filtering on the mapped signal to convert the mapped signal into a filtered signal, wherein the pre-filtering is finite impulse response filtering, a bandwidth of the filtered signal is less than a bandwidth of the mapped signal, and the filtered signal is a baud rate signal;
• and
• perform waveform forming according to the filtered signal to obtain a shaped signal;
• and
• wherein the analog-to-digital converter is configured to perform digital-to-analog conversion on the shaped signal to obtain an analog signal, and to send the analog signal to the receiver.

A receiver, comprising:

• an analog-to-digital converter, configured to perform analog-to-digital conversion on an analog signal to obtain a digital signal;
• and
• a processor, configured to:
• perform equalization and phase retrieval on the digital signal to obtain an equalized and retrieved signal;
• perform post-filtering on the equalized and retrieved signal to convert the equalized and retrieved signal into a filtered signal, wherein the post-filtering is finite impulse response filtering, and a bandwidth of the equalized and retrieved signal is greater than a bandwidth of the filtered signal;
• and
• perform sequence detection on the filtered signal to obtain a sequence signal.