Patent ID: 7624419

Claim:
A retransmitter characterized by comprising: a high-frequency input unit to which a receiving antenna for receiving a digital broadcasting wave is connected; a high-frequency output unit to which a retransmission antenna for retransmitting the digital broadcasting wave is connected; a section for acquiring a frequency selection signal which is a signal fed from a digital broadcasting receiver, said frequency selection signal corresponds to indication as to a channel that is selected by the digital broadcasting receiver; and a selecting and feeding section for selecting, by a selection filter, out of high-frequency signals inputted from said high-frequency input unit, a high-frequency signal having a frequency corresponding to said frequency selection signal and feeding the selected high-frequency signal to said high-frequency output unit, said selecting and feeding section comprises a first gain controller for making the level of the high-frequency signal inputted from the high-frequency input unit constant, a pass frequency variable filter for selecting the high-frequency signal having the frequency corresponding to the frequency selection signal, and a second gain controller for controlling transmission power of the selected high-frequency signal, and a section for acquiring a gain control signal fed from said digital broadcasting receiver and feeding a control signal to the second gain controller, and that the transmission power of the high-frequency signal is controlled by the second gain controller under control from said digital broadcasting receiver; wherein the digital broadcasting wave, on the selected channel, having the frequency corresponding to said frequency selection signal, is retransmitted by the high-frequency output unit without changing the frequency of said digital broadcasting wave on said selected channel.