A diversity receiver, comprising: a first main channel comprises an antenna diplexer, a first main transmission channel and a first main receiving channel, the first main transmission channel and the first main receiving channel are coupled to a main antenna by using the antenna diplexer, the first main transmission channel is configured to: generate a first transmit signal according to a first baseband signal, and send the first transmit signal to the main antenna by using the antenna diplexer, and the first main receiving channel is configured to generate a third baseband signal according to a second receive signal received from the main antenna; a first diversity channel comprises a tunable bandpass filter with a tunable passband and a first diversity receiving channel, the first diversity receiving channel is coupled to a diversity antenna by using the tunable bandpass filter, the tunable bandpass filter is configured to adjust the passband bandwidth of the tunable bandpass filter so that the band bandwidth of a first received signal received from the diversity antenna is contained within the passband bandwidth of the tunable bandpass filter and such that the band bandwidth of the first transmitted signal is excluded from the passband bandwidth of the tunable bandpass filter, and the first diversity receiving channel is configured to generate a second baseband signal according to the filtered first receive signal, wherein the second baseband signal and the third baseband signal are diversity receive signals; and wherein each of the first main transmission channel, the first main receiving channel, and the first diversity receiving channel is a zero intermediate frequency, ZIF, channel, and wherein the first main receiving channel and the first diversity receiving channel multiplex a same oscillator to provide same local oscillator, LO, signals for downconverting radio frequency signals of the same frequency at the first diversity receiving channel and the first main receiving channel. a first main channel comprises an antenna diplexer, a first main transmission channel and a first main receiving channel, the first main transmission channel and the first main receiving channel are coupled to a main antenna by using the antenna diplexer, the first main transmission channel is configured to: generate a first transmit signal according to a first baseband signal, and send the first transmit signal to the main antenna by using the antenna diplexer, and the first main receiving channel is configured to generate a third baseband signal according to a second receive signal received from the main antenna; a first diversity channel comprises a tunable bandpass filter with a tunable passband and a first diversity receiving channel, the first diversity receiving channel is coupled to a diversity antenna by using the tunable bandpass filter, the tunable bandpass filter is configured to adjust the passband bandwidth of the tunable bandpass filter so that the band bandwidth of a first received signal received from the diversity antenna is contained within the passband bandwidth of the tunable bandpass filter and such that the band bandwidth of the first transmitted signal is excluded from the passband bandwidth of the tunable bandpass filter, and the first diversity receiving channel is configured to generate a second baseband signal according to the filtered first receive signal, wherein the second baseband signal and the third baseband signal are diversity receive signals; and wherein each of the first main transmission channel, the first main receiving channel, and the first diversity receiving channel is a zero intermediate frequency, ZIF, channel, and wherein the first main receiving channel and the first diversity receiving channel multiplex a same oscillator to provide same local oscillator, LO, signals for downconverting radio frequency signals of the same frequency at the first diversity receiving channel and the first main receiving channel.