FPGA Realization Of Fast Channel Rs+interleaving Composite Coding In Atmospheric Optical Communication

Satallite optical communication deserves to be researched. We can acqurie higher transmission speed and better transmission quality between satellite and satellite, satellite and terrene by setting up laser link. Now, it has draw a lot of attention from all the world, many research departments are doing the research for it when more and more other deparments are planing to join them.Atmospheric optical communition is a important part of satellite optical communication, but atmospheric optical communication is under influences of many factors of atmosphere. And sometimes objects which is in communication procedure may interrupt the link. The intensity of the signal which is attenuated because of long transmission distance demands higher intensity to acquire low BER. The theory of channel coding technology is that some redundancies is added to information codes. So it can make use of the checkout polynomial to correct errors at the sink port. We can enhance the anti-interference ability of information by using this method, it help the system to get low BER rate and coding gain.Firstly, this paper introduces the purpose and application of the satellite free space optical communication and specially analyzes the development status quo of channel coding in FSO system. After introducing the bacis theory of error controlling coding and specially introduces the encoding and decoding arithmetics of Reed Solomon code, it introduces the correlative theories of interlace technology. Then this paper presents a improved interleaving mode basic from traditional interleaving mode and identifies that improved one is better than traditional one. After analyzing the influences of atmosphere on FSO link, this paper establishs a simulation model making use of measured data and carries out some simulation research into channel coding. This work will provide some reference to further research. After that, encoder , decoder of RS(15,9), improved matrix interleaver and deinterleaver are realized respectively in electrocircuit by making use of FPGA. Data buffers and port controllers are also designed and realized to satisfy the need of communticaton system. At last, respectively manoeuvres modularized encoding interleaver and deinterleaving decoder at the transmit port and sink port of channel coding system of atmosphere on FSO link. It is to say, channel coding system is realized in electrocircuit by using FPGA. At last, experiment of interleaved RS code used in atmosphere on FSO link was carried out in the laboratory. It testifies that interleaved RS code will ameliorate the quality of atmosphere on FSO link obviously.