Solution 1: Tonghui split QAM modulator_design of self-built digital TV front-end system

The program source of this program comes from satellites, provincial and municipal networks, and self-run programs. The free satellite program is received by the DVB-S/S2 four-in-one streamer and converted into a transparent TS stream, and the encrypted satellite program is received by the DVB-S/S2 four-in-one CI streamer (four-in-one card machine) and converted into a transparent TS stream. Transparent TS stream, programs from provincial and municipal networks are received by DVB-C four-in-one CI code streamer and converted into transparent TS stream, self-created programs are compressed and encoded into transparent TS stream by four-in-one encoder, EPG, advertisement and other data Received by the DVB matrix and converted into a transparent TS stream, all converted transparent TS streams are multiplexed by a multiplexer, scrambled by an independent scrambler, and then modulated into a radio frequency signal by a QAM modulator, and then mixed by the mixer, and then passed through the cable The transmission network transmits to the user's set-top box.

In the process of system construction, the corresponding equipment can be appropriately increased or decreased according to the number of programs to be transmitted.