This application relates to the field of communications technologies. A method includes: A first device receives first configuration information sent by a second device. The first configuration information includes at least one of information about a reference signal, frequency range information of a radio frequency signal, or bandwidth range information. The first device measures a first reference signal set, to obtain a first measured value. The first reference signal set includes at least two reference signals. The first device determines an expansion factor α based on the first configuration information. The first device determines a second measured value based on the first measured value and the expansion factor α.