The Research And Development Of FH Data Communication Based On Special AIS Data Transceiver

Special AIS data transceiver is a wireless communication device which not onlyhas AIS (Automatic Identification System) function, but also provides functions ofspecial target identification, navigation and communication with special objects. Itemploys two independent radio channels which are AIS channel and special FH datachannel. The FH data communication function determines the performance of thespecial channel. Currently, the technology of FH data communication has been appliedin many communication domains. In this system, the key technical point is to achieve alow BER FH data communication working in TDMA (time division mulptiple access)networking.The background of the project and the application value are presented in the firstchapter of this dissertation. In the second chapter, it introduces the theory of SpecialAIS data transceiver, working flows of AIS channel and special channel, and the basictheory of TDMA networking. After that, the hardware’s structure and the fuctions ofeach module are given.The third and fourth chapters contain emphasis of this dissertation，which discussthe hardware design and the key technologies of implementing the FH datacommunication. In hardware design, a usual and flexible structure is used, as the corechips adopt FPGA and ARM. The ARM chip is used as control unit taking charge ofthe communication between ports, controlling the state of transceiver, managing theparameters of FH. And the FPGA chip is used as signal processing unit, providingfunctions such as generating and managing time sequences, processing FH operations,managing the synchronization and coding and decoding. The combination of ARM andFPGA produces a more flexible and effective system.For the key technologies, according to the character of FH data communication inTMDA networking, the implementations of synchronization of TDMA networking, FHand coding are given respectively. As the base of communication, the synchronizationof networking including the design of time slot and the achievement of time slotsynchronization are presented. The synchronization is a key technology of FH communication. This project adopts the method of synchronization head. In thisdissertation, the format of synchronization head is given. Furthermore, analysises ofthe performance of correlation code, the capture probability and false probability aregiven.