Abstract

In a television signal transmission system, CS broadcasting signals received via a master antenna are converted into intermediate frequency signals in an LNB (Low Noise Block Down Converter). The CS intermediate frequency signals then undergo conversion of the modulation format, for example, from QPSK into 64-QAM, so that CS broadcasting signals from each transponder, having a bandwidth of, for example, 27 MHz, are accommodated in a narrower bandwidth, for example, 6 MHz, which is equivalent to one channel of terrestrial broadcasting services. Then, the signals accommodated in the narrower bandwidth is frequency-shifted into a vacant frequency band in the VHF band or the UHF band. Accordingly, the CS signals accommodated in the narrower band and frequency-shifted into the vacant band are multiplexed with terrestrial broadcasting signals in the VHF and UHF bands and BS intermediate frequency signals so that all these signals are delivered to each household via a single cable.