A radio frequency, RF, receiver, comprising a receiver front-end , the receiver front-end comprising: a passive mixer , having an input for receiving a radio frequency signal and an output for generating an output signal at a baseband : frequency or an intermediate frequency, wherein the input impedance and output impedance of the passive mixer are configured as high impedances so that the receiver front-end matches with a high impedance of baseband circuits and intermediate-frequency circuits, respectively; a gain control circuit , coupled between the output of the passive mixer and an input of an amplifier ; and the amplifier , coupled to the gain control circuit ; wherein the gain control circuit is arranged to detect a signal at the input of the amplifier to adjust a gain value that is exerted on the output signal generated at the output of the passive mixer to maintain linearity of the amplifier , characterized in that the gain control circuit comprises: a passive attenuation circuit , coupled between the output of the passive mixer and the input of the amplifier ; and a detector , coupled to the passive attenuation circuit and the input of the amplifier , for sensing a level of the signal at the input of the amplifier , and sending a control signal to control the passive attenuation circuit to adjust the gain level to perform gain attenuation for a level of the output signal generated at the output of the passive mixer . a passive mixer , having an input for receiving a radio frequency signal and an output for generating an output signal at a baseband : frequency or an intermediate frequency, wherein the input impedance and output impedance of the passive mixer are configured as high impedances so that the receiver front-end matches with a high impedance of baseband circuits and intermediate-frequency circuits, respectively; a gain control circuit , coupled between the output of the passive mixer and an input of an amplifier ; and the amplifier , coupled to the gain control circuit ; wherein the gain control circuit is arranged to detect a signal at the input of the amplifier to adjust a gain value that is exerted on the output signal generated at the output of the passive mixer to maintain linearity of the amplifier , characterized in that the gain control circuit comprises: a passive attenuation circuit , coupled between the output of the passive mixer and the input of the amplifier ; and a detector , coupled to the passive attenuation circuit and the input of the amplifier , for sensing a level of the signal at the input of the amplifier , and sending a control signal to control the passive attenuation circuit to adjust the gain level to perform gain attenuation for a level of the output signal generated at the output of the passive mixer . a passive attenuation circuit , coupled between the output of the passive mixer and the input of the amplifier ; and a detector , coupled to the passive attenuation circuit and the input of the amplifier , for sensing a level of the signal at the input of the amplifier , and sending a control signal to control the passive attenuation circuit to adjust the gain level to perform gain attenuation for a level of the output signal generated at the output of the passive mixer . <EOS>