Gain control method and device

The invention relates to a gain control method and a device, and the device comprises an automatic gain controller which detects the input power of a primary synchronization signal PSS in an input signal in real time. The method comprises the steps of acquiring downlink PSS rated power serving as a gain control threshold of the automatic gain controller; and controlling an automatic gain controller to adjust a gain attenuation value according to the PSS input power and the downlink PSS rated power, wherein the gain attenuation value is used for adjusting the uplink gain and the downlink gain.According to the method, the downlink PSS rated power is used as the downlink PSS rated power of the automatic gain controller; the magnitude relationship between the input PSS input power and the downlink PSS rated power is detected to control the level of the input signals of the uplink and the downlink; and the uplink gain and the downlink gain are further controlled to prevent frequent switching of signal levels, and