This application discloses a signal transmission method, including: mapping a first sequence into a first subcarrier group, and mapping a second sequence into a second subcarrier group. The subcarriers included in the first subcarrier group and the second subcarrier group are subcarriers on a same time domain symbol. The subcarriers in each of the first subcarrier group and the second subcarrier group are evenly distributed subcarriers. The first sequence is a Fourier transform sequence of a third sequence. The second sequence is a Fourier transform sequence of a fourth sequence. The elements at a same location in the third sequence and the fourth sequence are not both non-zero elements.