Patent ID: 8364110

Claim:
A radio frequency (RF) front end circuit connected to an external antenna array, the RF front end circuit comprising: a processor; a main receiving (Rx) path and an adjustment path connected between the processor and the external antenna array in parallel, the adjustment path comprising an adjustment transmitting (Tx) path, an adjustment Rx path, and a digital signal processing module (DSP), the adjustment Tx path comprising a coupling switch; and a coupling module with a first end coupled to the main Rx path, and a second end connected to the coupling switch; wherein the RF front end circuit is selectively operable in a normal mode or an adjustment mode under control of the processor; when the RF front end circuit operates in the normal mode, the main Rx path and the adjustment Rx path respectively receive and process signals from the external antenna array independently; and when the RF front end circuit operates in the adjustment mode, the processor directs the coupling switch to connect the coupling module to the adjustment Tx path, the adjustment Rx path receives and demodulates a first analog signal from the antenna array, and transmits the first analog signal to the DSP, the DSP converts the first analog signal to a digital signal, clips a peak part of the digital signal, converts the digital signal to a second analog signal, and transmits the second analog signal to the adjustment Tx path, the adjustment Tx path modulates and reverses the phase of the second analog signal, and transmits the second analog signal to the coupling module, and the coupling module couples the second analog signal to the main Rx path to counteract a noise received by the main Rx path.