Mode S Transponder Receiver Digital Processing System Design

The MSSR Mode S technology,which was introduced firstly for the purpose of Air Tranfic Control(ATC) system,is based on the individually addressing and selective interrogation technology.The Mode S can overcome many problems exist in Mode A/C,such as signal interference, limited aircraft identification,garble and fruit,and provides the ability to build digital data link.Many countries and organizations do them best to support researches about the communication,navigation and surveillance technology,which are all based on the Mode S,and many productions have been adopted step by step by the International Civil Aviation Organization(ICAO) .So,to research the key technologies of Mode S will contribute a lot to the development of domestic aviation system,especially for the Air Control System, Identification Friend Foe and Navigation System.A kind of MSSR Mode S plot extractor system based on FPGA+DSP architecture is introduced in this paper.This system adopt three algorithms to get information of Mode S reply correctly in high dense A/C jamming environments,which are preamble detecting algorithm,codes getting algorithm based on multi-samples and multi-parameters,and error detection and correction algorithm based on confidence analyzing.In this project,the author take part in the research of algorithm,system architecture design,and system hardware design.At the same time,the author mainly charge the research of simpling the preamble detecting algorithm for implementing and then implement the simpled preamble detecting algorithm on the FPGA.Finally, the system's main functions were simulated and tested by author.