Detailed cable TV set-top box

The basic function of the cable set top box (Cable Set Top Box) is to receive digital TV broadcast programs. The tuning module receives RF signals and down-converts them to IF signals, then converts them into digital signals, and then sends them to the QAM demodulation module for demodulation. Output MPEG transport stream serial or parallel data.

The demultiplexing module receives the MPEG transport stream and extracts PES data for a program, including video PES and audio PES. The video PES is sent to the video decoding module, takes out MPEG video data, and decodes the MEPG video data, and then outputs it to a PAL/NTSC encoder, encodes it into an analog television signal, and then outputs it via a video output circuit. The audio PES is sent to the audio decoding module, the MPEG audio data is taken out, and the MPEG audio data is decoded, and the PCM audio data is output to the PCM decoder. The PCM decoder outputs the stereo analog audio signal and is output by the audio output circuit.

Cable TV digital set-top boxes can support almost all broadcast and interactive multimedia applications, including digital television broadcast reception, EPG, NVOD, PPV, software online upgrades, data broadcasting, Internet access, e-mail, IP telephony, VOD, and more.