| 摘要 |
A cable television channel security system for installation at a subscriber location to control access to one of more channels of RF signals transmitted from a headend location via conventional cable means. The system is divided into two major subassemblies, a so-called address module and a switch module, the latter including one or more conventional traps. The address module receives a sequence of coded signals selectively inserted through a personal computer at the cable system business office and carried on portions of the RF signals transmitted at the headend. The coded signals include a first portion unique to each subscriber location and a second portion indicating which of the premium channels are to be directed to traps, and which are to bypass the traps of the switch module. As signals are transmitted and received in the clear, i.e., without descrambling, with reception of premium channels controlled entirely from the business office by addressing the desired subscriber location, and the individual traps positioned thereat within a securely closed housing.
|
