Architecture Design And Hardware Implementation Of IPTV Gateway

With the high-speed development of access network, widely need of multi-service bearing and strong promotion of user's station network intellective terminal, FTTH and Triple-Play become the best information total solutions of enterprise and residential area. This paper makes a research with how to amalgamate CATV, telephone audio service and internet service, and designs a IPTV gateway, which transforms the CATV signal, including analog and digital TV signals, and CVBS to group-casting signal that can amalgamate CATV network and internet.CATV signal includes analog and digital TV signals, which all use radio signal as carrier wave to send, transmit and receive with broadcasting to user terminal. Analog TV signal has only one TV program with one frequency and it hasn't been encrypted and disturbed, the user terminal can change the TV programs by turn the frequency; digital TV signal has got many TV programs with only one frequency and they have almost all been encrypted and disturbed, the user terminal must turn the frequency and filtrate the program number to change the TV programs. Aiming at the similarities and differences of the two TV signals, IPTV gateway's signal processing includes radio receiving, conditional access, A/D converting, MPEG2 encoding, TS de-multiplex and re-multiplex, group-casting package and so on.This gateway system design has three parts: analog TV signal process daughter card, digital TV signal process daughter card, power supply and output signal integrated backboard design. The analog TV signal process daughter card includes analog tuner, A/D converters, MPEG2 encoder, network processor ; The igital TV signal process daughter card includes digital tuner, conditional access block, DSP, FPGA, network processor and so on.At last, we test the signal quality before and after signal process with Stream analyzer, validate that the hardware interface design is good with logic simulation, and realize the transition from CATV to Ethernet group-casting signals with embedded software design.