Patent ID: 8019027

Claim:
A digital broadcasting receiver comprising: a variable gain amplifier for amplifying an electric wave received through an antenna, a gain of the variable gain amplifier being variable; a plurality of tuners for performing selection of broadcastings, and amplification, each of the plurality of tuners being connected to the variable gain amplifier through a distributor; and a signal processing portion for judging degradation states of digital signals obtained by demodulating output signals from the plurality of tuners, and varying the gain of the variable gain amplifier in accordance with a judgment result so as to improve the degradation states of the digital signals obtained by demodulating the output signals from the plurality of tuners, respectively, wherein one of the plurality of tuners corresponds to a main picture, and another of the plurality of tuners corresponds to a sub picture, and when a value representing the degradation state of the digital signal obtained by demodulating the output signal from the one tuner corresponding to the main picture is smaller than a threshold, and a value representing the degradation state of the digital signal obtained by demodulating the output signal from the another tuner corresponding to the sub picture is equal to or larger than the threshold, the signal processing portion increases or decreases the gain of the variable gain amplifier so as to reduce the value representing the degradation state of the digital signal obtained by demodulating the output signal from the another tuner corresponding to the sub picture.