A radio frequency circuit. In the circuit, a first directional coupler receives a second transmit signal, uses a part of the second transmit signal as a third transmit signal, directly sends the third transmit signal to a first port of a circulator, and obtains a first coupling signal from the second transmit signal; the circulator outputs the third transmit signal through a second port; an impedance tuner transmits the third transmit signal to an antenna port and transmits, to the second port of the circulator, a first input signal from the antenna port; the circulator inputs the first input signal to a second directional coupler through a third port; the second directional coupler obtains a second coupling signal from the first input signal; and a controller adjusts impedance of the impedance tuner according to the first coupling signal and the second coupling signal.