A signal processing method, comprising: generating a first training signal, adjusting a power of the first training signal, and adding a first training signal with an adjusted power to a first service signal to obtain a first combined signal; and collecting a second combined signal output by a power amplifier or reflected by a post-stage circuit to which the first combined signal is input, extracting a second training signal from the second combined signal, and performing a signal processing based on the second training signal, the signal processing comprising correcting a digital predistortion DPD model, characterized in that : extracting the second training signal from the second combined signal comprises: separating the second combined signal into a second service signal that does not include the second training signal and a third combined signal that includes the second training signal; extracting a predetermined model based on the first service signal and the second service signal; wherein the predetermined model comprises a power amplifier model, or a digital predistortion model and the power amplifier model; calculating a third service signal in the third combined signal based on the first service signal and the predetermined model; and calculating the second training signal in the third combined signal based on the third combined signal and the third service signal. generating a first training signal, adjusting a power of the first training signal, and adding a first training signal with an adjusted power to a first service signal to obtain a first combined signal; and collecting a second combined signal output by a power amplifier or reflected by a post-stage circuit to which the first combined signal is input, extracting a second training signal from the second combined signal, and performing a signal processing based on the second training signal, the signal processing comprising correcting a digital predistortion DPD model, characterized in that : extracting the second training signal from the second combined signal comprises: separating the second combined signal into a second service signal that does not include the second training signal and a third combined signal that includes the second training signal; extracting a predetermined model based on the first service signal and the second service signal; wherein the predetermined model comprises a power amplifier model, or a digital predistortion model and the power amplifier model; calculating a third service signal in the third combined signal based on the first service signal and the predetermined model; and calculating the second training signal in the third combined signal based on the third combined signal and the third service signal. separating the second combined signal into a second service signal that does not include the second training signal and a third combined signal that includes the second training signal; extracting a predetermined model based on the first service signal and the second service signal; wherein the predetermined model comprises a power amplifier model, or a digital predistortion model and the power amplifier model; calculating a third service signal in the third combined signal based on the first service signal and the predetermined model; and calculating the second training signal in the third combined signal based on the third combined signal and the third service signal. <EOS>