Research And Implement A New Kind Of Modem Technology

Nowadays, updating the performance of optical communications system via coding and modulation technology such as FEC, QPSK, DQPSK etc become more and more popular and realistic. Currently, most of modulation technique in fiber adopt ASK or OOK and the data controls the switch-on and switch-off of beam of light. The modulation technique like DPSK and DQPSK is tested and adopted recently to solve kinds of dispersion issue. Even the several decades old modulation technique—dual binary modulation is becoming valuable, and these modulation techniques expand the 40Gbits/s optical transmission. We expect more and more kind of modulation techniques will be researched and developed during the period of optical communications system processing to 40Gbits/s even 100Gbits/s.Digital communication has become much more important and the network is developing toward to broadband multi-media digital network including data, voice, picture and video. Therefor, the modulation technique is switching from analog to digital. In this paper, a new kind of digital modulation—Non-Orthogonal Multi-Carriers Modulation(NO-MCM) is researched and validated combining with broadband access technology xDSL. And also complete the data processing including FEC(Reed-Solomon coding), scrambling, interleaving, constellation mapping, cyclic prefix etc and facilitate the study on access technology in the future through comparing the local access technology such as DSL and FTTH.In this paper, the circuit control system design mainly about the development of software& hardware system of DSP& FPGA is implemented. The system complete a real data transmission in a cable line (<5m) at the speed(>10Mbps) and the Bit Error Rate(BER) is lower than le-12.