Reception electric field level detection circuit

Abstract

A reception electric field level detection circuit comprises a frequency conversion circuit, an IF filter and a demodulation circuit for outputting a demodulation signal, which are connected successively to an antenna. The reception electric field level detection circuit further comprises a reception electric field detection circuit for receiving the output of the IF filter as an input thereto and detecting the reception electric field level value of the received wave, and a discrimination circuit. A carrier sent out from a mobile radio unit to a stationary radio unit is received by the antenna and inputted to the demodulation circuit and the reception electric field detection circuit by way of the frequency conversion circuit and the IF filter. The discrimination circuit discriminates a modulated portion and a non-modulated portion of the carrier inputted to the reception electric field detection circuit and controls the reception electric field detection circuit so that the reception electric field detection circuit detects a reception electric field level value from the non-modulated portion of the carrier.

Dependencies are inferred from the claim text.