A detection method includes determining a first frequency point of N frequency points, transmitting a radio signal in a first frequency band in N frequency bands. One of the N frequency bands partially overlaps at least one frequency band in other N−1 frequency bands, and an absolute value of a difference between lowest frequencies of any two frequency bands of the N frequency bands is not less than a first threshold (F), or the N frequency bands have at least one second frequency band that partially overlaps the first frequency band, and an absolute value of a difference between a lowest frequency of each second frequency band and a lowest frequency of the first frequency band is not less than F.