Radio frequency front-end circuit and operation method thereof

A radio frequency front-end circuit, comprising:

• a first linear amplifier, configured to receive a radio frequency signal, perform a high-frequency amplification on the radio frequency signal to generate an amplified radio frequency signal, and down-convert the amplified radio frequency signal into an intermediate frequency signal;
• a second linear amplifier, coupled to the first linear amplifier, configured to receive the intermediate frequency signal, and perform a low-frequency amplification on the intermediate frequency signal to generate an amplified intermediate frequency signal;
• and
• a calibration unit, coupled to the first linear amplifier and the second linear amplifier, configured to receive a voltage gain fed back from the second linear amplifier, and execute an auto-calibration procedure according to the voltage gain fed back from the second linear amplifier to search for a current value of an input current of the first linear amplifier, where the current value corresponds to a maximum voltage gain of the first linear amplifier.