Patent ID: 8804882
Filing Date: 2014-08-12
Classification: H03G,H04L

Abstract:
1. A receiving apparatus comprising: a first amplifier that amplifies a received wave using high frequency; a frequency converter that performs frequency conversion on a signal output from the first amplifier from a frequency band of the first amplifier to a frequency band at a later stage; an analog filter that filters the signal that has been subjected to frequency conversion by the frequency converter; a second amplifier that amplifies the signal, which was filtered by the analog filter, using a demodulation frequency; a converter that converts the output signal from the second amplifier to a digital signal; a digital filter that filters the digital signal output from the converter to a desired frequency band; a demodulator that demodulates the digital signal that was filtered by the digital filter; and a digital circuit to which the digital signal output from the converter before being filtered by the digital filter and the digital signal that was output from the converter and then filtered by the digital filter are inputted; wherein the digital circuit comprises: wherein the gain control unit (i) compares a threshold value that indicates a settable gain ratio with the power difference; (ii) performs control so that, when the power difference is greater than the threshold value, the gain ratio of the first amplifier is lowered; and (iii) performs control so that, when the power difference is less than the threshold value, the gain ratio of the first amplifier is raised.