Based On Multi-Channel DVB-C Channel Coding And Modulation System Research And Design

Along with the numeral broadcast television industry and the Internet industry high speed fusion development, many services interlock complexly, emerge one after another incessantly, This the equipment overall performance set a higher request to the broad electricity system front end.The traditional modulation system already cannot satisfy the present each kind of service development the demand, in particular in the equipment management and the maintenance aspect, could be quite complex. This article combines digital signal processing technology and relevant industry standards, design a multi-channel coding and modulation for DVB-C channel system, the system schema design is simple, and can achieve full coverage of national cable network frequency, greatly saves the investment costs in the construction of the network.The paper first to realized the multichannel DVB-C channel coding and the modulation system basic theory has carried on the description, with emphasis elaborated this system realization method. Then described has flowed the input from MPEG-2 TS to start, process channel code processing, baseband filter processing and multichannel numeral radio frequency modulation and so on realization process; Finally introduced this system research and development test environment and some research and development achievement and so on. This article uses the slip frequency frequency conversion technology, filters out the clutter including the digital filter technology; On the construction, uses programmable logical array (FPGA) to output the fine harmonious parameter for the D/A converter, guaranteed DAC outputs the perfect orthogonal IQ signal, actuates the modulator work in the 50MHZ-1GHz frequency band, the test result to indicate this system can satisfy 96 channel DVB-C channel coding and the modulation system performance requirement.