| 摘要 |
<p>A television signal transmitting system for use in television transmission in one of a number of television channels which are spaced apart in frequency by nominally vacant channels, which system transmits a mixed signal in which a main signal of one channel of a television signal is combined with an additional signal, the system comprising: modulating means for two-phased quadrature modulating said additional signal combined with said main signal so as to become symmetrical to a vestigial sideband component as a central frequency which is a modulating frequency of said main signal when said additional signal is demodulated, wherein modulation of the additional signal is such that it is transmitted as its lower sideband which overlaps the lower part of the frequency spectrum of the main channel band and the upper part of the vacant channel which is adjacent to, and lower in frequency than, the main channel band.</p> |
