Digital television system and descrambling method of simultaneously supporting multipath programs of different frequency points

Abstract

The embodiment of the present invention discloses a digital television system and a descrambling method of simultaneously supporting multipath programs of different frequency points. When a command for broadcasting or recording of multipath scrambled programs is received, a transport stream of the program of one path is injected into a condition receiving module to perform descrambling, authorization management information and authorization control information corresponding to the programs of other paths are analyzed, and a conditional receiving module is used to decrypt the control words of the program of each path. The program of each path is descrambled according to the control words for broadcasting or recording. The above-mentioned descrambling method provided by the invention does not need to inject the transport streams of different frequency programs into the conditional receiving module and only injects the transport stream of one program into the conditional receiving module and only transmits the authorization related information of the programs of other paths. The control words of the programs of different frequency points are acquired under the premise that the same conditional receiving module is used, so that the multipath programs can be simultaneously descrambled and the digital television multipath programs can be simultaneously played or recorded.

Description

technical field [0001] The invention relates to the field of digital television systems, in particular to a digital television system and a descrambling method for simultaneously supporting multiple programs with different frequency points. Background technique [0002] As our country vigorously promotes the conversion from TV analog signal to digital signal, digital TV has been fully popularized. At present, the global digital TV system is mainly divided into the following types, among which the standard adopted by the United States is Advanced Television System Committee (ATSC for short); the standard adopted by Europe is Digital Video Broadcasting (DVB for short). ; The standard adopted in Japan is Integrated Services Digital Broadcasting (ISDB). Many countries, including my country, currently use DVB as the digital TV system. Not compatible. For example, the CAS solution adopted by Shandong Radio and Television is Irdeto, while the CAS solution adopted by Sichuan Radio...

AI Technical Summary

Problems solved by technology

A CAM card can only descramble the programs under one frequency point. If the programs need to exist under different frequency points, the same CAM card cannot be used for descrambling.

If the programs to be played are all at the same frequency point, it can support the simultaneous playback of multiple programs; if the programs to be played are not at the same frequency point, a single CAM card cannot support the descrambling of multiple programs, so it cannot Realize simultaneous playback or recording of multiple programs

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