Signal processing method, system, sending end, and receiving end

A signal processing method, a system, a sending end, and a receiving end. The method comprises: receiving a signal transmitted through a channel; demodulating the signal; replacing a first piece of padding data at a padding position in the signal into a second piece of padding data; and performing error correction and decoding. The system comprises a receiving end and a sending end. The receiving end comprises: a receiving module used for receiving a signal transmitted through a channel; a demodulation module used for demodulating the signal; a replacement module used for replacing a first piece of padding data at a padding position in the signal into a second piece of padding data; and a decoding module used for performing error correction and decoding processing. By implementing the embodiments of the present invention, before the receiving end performs error correction and decoding on the received signal, the first piece of padding data to which an error may occur in transmission may be replaced into the reliable second piece of padding data which does not require error correction and decoding, so that the correction and decoding capabilities focus on useful actual data, thereby improving the effective encoding gain.