A signal transmission method, comprising: mapping, by a transmit end (700, 800), a first sequence into subcarriers in a first subcarrier group, and mapping, by the transmit end (700, 800), a second sequence into subcarriers in a second subcarrier group, wherein there is no same subcarrier in the first subcarrier group and the second subcarrier group, the subcarriers comprised in the first subcarrier group and the second subcarrier group are subcarriers on a same time domain symbol, the subcarriers in the first subcarrier group are evenly distributed subcarriers in a subcarrier set, two adjacent subcarriers in the first subcarrier group are spaced by L-1 subcarriers in the subcarrier set, the subcarriers in the second subcarrier group are evenly distributed subcarriers in the subcarrier set, two adjacent subcarriers in the second subcarrier group are spaced by L-1 subcarriers in the subcarrier set, the first sequence is a Fourier transform sequence of a third sequence, the second sequence is a Fourier transform sequence of a fourth sequence, elements at a same location in the third sequence and the fourth sequence are not both non-zero elements, the third sequence and the fourth sequence each are a sequence in which at least one element is a non-zero element, the subcarrier set comprises LM subcarriers that are evenly distributed in frequency domain, and both L and M are positive integers; generating, by the transmit end, a sending signal based on elements on the first subcarrier group and the second subcarrier group; and sending, by the transmit end, the sending signal wherein the first sequence comprises M elements: a 0, a 1,...., a M -1, and the first sequence is obtained by extending a base sequence c 0, c 1,...., c K -1 whose length is K, wherein M = p × K, a i = c i mod K × e j 2 πiu M, u is a value in 0,1,..., p -1, i is a variable, a value of i is 0,1,..., M -1, and both p and K are positive integers, wherein the second sequence comprises M elements: b 0, b 1,..., b M -1, and the second sequence is obtained by extending a base sequence d 0, d 1,...., d K -1 whose length is K, wherein b i = d i mod K × e j 2 πiv M, v is a value in 0,1,..., p -1, and v is not equal to u. mapping, by a transmit end (700, 800), a first sequence into subcarriers in a first subcarrier group, and mapping, by the transmit end (700, 800), a second sequence into subcarriers in a second subcarrier group, wherein there is no same subcarrier in the first subcarrier group and the second subcarrier group, the subcarriers comprised in the first subcarrier group and the second subcarrier group are subcarriers on a same time domain symbol, the subcarriers in the first subcarrier group are evenly distributed subcarriers in a subcarrier set, two adjacent subcarriers in the first subcarrier group are spaced by L-1 subcarriers in the subcarrier set, the subcarriers in the second subcarrier group are evenly distributed subcarriers in the subcarrier set, two adjacent subcarriers in the second subcarrier group are spaced by L-1 subcarriers in the subcarrier set, the first sequence is a Fourier transform sequence of a third sequence, the second sequence is a Fourier transform sequence of a fourth sequence, elements at a same location in the third sequence and the fourth sequence are not both non-zero elements, the third sequence and the fourth sequence each are a sequence in which at least one element is a non-zero element, the subcarrier set comprises LM subcarriers that are evenly distributed in frequency domain, and both L and M are positive integers; generating, by the transmit end, a sending signal based on elements on the first subcarrier group and the second subcarrier group; and sending, by the transmit end, the sending signal wherein the first sequence comprises M elements: a 0, a 1,...., a M -1, and the first sequence is obtained by extending a base sequence c 0, c 1,...., c K -1 whose length is K, wherein M = p × K, a i = c i mod K × e j 2 πiu M, u is a value in 0,1,..., p -1, i is a variable, a value of i is 0,1,..., M -1, and both p and K are positive integers, wherein the second sequence comprises M elements: b 0, b 1,..., b M -1, and the second sequence is obtained by extending a base sequence d 0, d 1,...., d K -1 whose length is K, wherein b i = d i mod K × e j 2 πiv M, v is a value in 0,1,..., p -1, and v is not equal to u.