RSSI estimation based on VGA control and threshold detection

摘要

A circuit for RSSI estimation includes a cascaded chain of variable gain amplifier stages, a threshold detector configured to output an indication signal according to a comparison of output of the cascaded chain of variable gain amplifier stages with a predetermined threshold, and an automatic gain controller configured to adjust gain of at least one variable gain amplifier of the cascaded chain of variable gain amplifier stages according to the indication signal. Each stage may include a switch module configured to electrically connect or disconnect an input of the variable gain amplifier of the at least one variable gain amplifier stage to/from an output of a previous variable gain amplifier stage according to a switch control signal.