The Study And Design Of SD TV Audio Cascade Multiplex System Based On FPGA

With the development of radio and video technology, production and broadcasting systems will gradually all-digital at TV station. The emergence of multi-channel stereo and viewers have become increasingly demanding of TV programs, digital audio multiplex technology has been greatly developed in recent years. At home and abroad digital audio multiplex solution usually use specific audio multiplex chip, ASIC can not correctly identify the gap in the video line blanking, resulting in the failure of cascade multiplex. To solve this problem, we Proposed a solution of FPGA-based digital audio cascade multiplex system.In the paper, we use the FPGA's inner RAM for caching audio data by address, and then multiplex in the original audio and new audio data packaged and re-multiplexed into the video line blanking, complete cascade multiplex process. Two core technologies of this paper, cascade multiplex and EDH processing technology is done within the FPGA. The design of the FPGA chip is Altera company's high-cost Cycloneâ…¢family EP3C25E144C8, use of the EDA platform Quartusâ…¡8.0 implements SDI receiver, digital audio interface, audio data packet detection, cascade multiplex core processing, EDH processing and other function. This design uses FPGA top-down and modular design, first divided the whole system into various functional modules, each module then needs to complete its function, and finally to integrate and optimize the entire system. Use the audio cascade multiplex technology, we put the original audio information of the video and new multiplex audio data re-packaged, then multiplexed in the video line blanking to ensure the lossless audio output. Meet the requirements of TV station production and broadcasting systems.FPGA-based digital audio cascade multiplex system, achieved the full acceptance and lossless audio output. The output sound quality of this system is good, and fast processing speed and ease of system upgrade. Fully reflects the real-time and flexible FPGA design.Has a positive meaning to our country's development of radio and video.