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.