Method and circuit arrangement for the prevention of unauthorised reception of scrambled television signals

Abstract

Abstract The method involves scrambling the television signals at a broadcasting centre according to an algorithm which changes with time, is stored essentially in the decoders which authorised subscribers are allocated and can be called up there for decoding. The authorised subscribers are assigned an address, which is stored both at the broadcasting centre and in the subscriber's decoder, in a memory in each case. When the address is later transmitted together with the scrambled television signals, additional information on the changing of the algorithm with time is imparted.

Inventors

• 👤 Günter Dipl.-Ing. Noetzel

Bibliographic Details