A signal processing method and a related device are provided. The signal processing method includes: determining that there are N directions for received signals corresponding to a same signal source; configuring beam directions of an antenna as the N directions; estimating delays of the N received signals received by using the antenna, and separately performing, by using the estimated delays of the N received signals, delay compensation on the N received signals to obtain N received signals obtained after delay compensation, where the N received signals are in a one-to-one correspondence with the N directions, and N is an integer greater than 1; and performing combining processing on the N received signals obtained after delay compensation. The technical solutions in embodiments of the present invention help increase a signal reception gain in a multipath scenario.