US Patent 10938438 Radio-frequency circuit

Disclosed is a radio-frequency (RF) circuit capable of performing an RF characteristic test in a test mode. The RF circuit includes: a test signal generator generating a test signal; an RF receiver, coupled to the test signal generator, transmitting the test signal and thereby generating a receiver analog signal; a coupling circuit transmitting the receiver analog signal to an RF transmitter in the test mode; the RF transmitter transmitting the receiver analog signal and thereby generating a transmitter analog signal; a test result generator, coupled between the RF transmitter and a test result output terminal, including a signal converter for generating a converted signal according to the transmitter analog signal in the test mode, wherein the output signal at the test result output terminal is the converted signal or originated therefrom and relates to the result of the RF characteristic test.