Patent ID: 8817923
Filing Date: 2014-08-26
Classification: H04N

Abstract:
1. A digital broadcast receiver comprising: a radio frequency auto gain control (RF-AGC) amplifier unit that amplifies, with its gain being controlled, an RF signal in a desired frequency band extracted from RF signals of a digital broadcasting wave; a first frequency converter unit that carries out frequency conversion of an output signal of the RF-AGC amplifier unit to a first IF signal in a first desired intermediate frequency band; a second frequency converter unit that carries out frequency conversion of the first IF signal to a second IF signal in a second desired intermediate frequency band; an intermediate frequency auto gain control (IF-AGC) amplifier unit that amplifies, with its gain being controlled, the second IF signal a detecting unit that detects an interfering wave in the digital broadcasting wave; an information acquiring unit that acquires information indicating a receiving state of the digital broadcasting wave; a decision unit that decides, when the detecting unit detects the interfering wave, the presence or absence of receiving performance deterioration in the digital broadcasting wave due to the interfering wave from the information supplied from the information acquiring unit; and a control unit that alters, when the decision unit decides that the receiving performance deterioration of the digital broadcasting wave is present, an operating point of the RF-AGC amplifier unit and a time constant of gain control in the RF-AGC amplifier unit, wherein altering the operating point reduces the receiving performance deterioration due to the interfering wave, and altering the time constant reduces the receiving performance deterioration due to fading.