Encrypting identification intercutting-preventing method for broadcasting program based on satellite transmission

The invention relates to an encrypting identification intercutting-preventing method for broadcasting program based on satellite transmission, and the method comprises the following steps: selecting at least one frequency value, the frequency of which is above 16kHz, as a characteristic frequency; modulating an original characteristic signal onto the characteristic frequency; after performing thepretreatment and amplitude control on an original digital audio frequency signal and the modulated characteristic signal, superposing the signals and broadcasting the signals on an emitting station; performing band-pass digital filter on the received signals by a receiver; extracting the characteristic signal and performing spectrum analysis and demodulation on the characteristic signal; judging the validity of the received signal according to a preset judging system; and controlling whether to supply a broadcasting signal to a downstream device according to the judging result, and supplying the alarm information. By