single cable distribution (scd)

In antenna systems, there are two technical concepts with which several subscribers can receive different television and radio programs simultaneously via a single antenna cable: The single-cable system and the Unicable. Both antenna system concepts take into account an unproblematic changeover in the case of new reception equipment such as a satellite dish.

The single-cable system divides the entire frequency range of the antenna cable into individual frequency ranges that are assigned to the various broadcast services. The unicable concept, on the other hand, is designed for satellite reception and uses special LNB converters.

The coaxial cable used in single-cable systems is a broadband high-frequency cable over which all broadcast services can be transmitted. The broadcast services are fed into the single-cable system directly, without frequency conversion. This means that FM broadcasting, analog terrestrial TV, terrestrial digital TV( DVB-T), digital TV from cable distribution networks( DVB-C) and satellite-based digital TV( DVB-S) are transmitted in different frequency bands via the coaxial cable. This is directly possible because different transmission frequencies are assigned to the various broadcast services. One prerequisite, however, is that the high-frequency cable must be able to transmit all frequency ranges up to 2.250 GHz. Because that is the frequency range for DVB-S, which is generated as an intermediate frequency in the LNB converter.

VHF broadcasting, which occupies the frequency range between 88 MHz and 108 MHz, is fed in directly according to this scheme. The frequency band reserved for cable TV between 105 MHz and 465 MHz and terrestrial TV and digital TV transmitted in the UHF band can also be fed in directly, occupying the frequency range between 470 MHz and 855 MHz.