Research On Anti-jamming Technologies Of Satellite Tele-control And Tele-measure Communication

As the important tache, telemetry and telecontrol ensures the normal operation of the satellite communication system. How to improve the anti-jamming capability of TT&C (telemetry telecontrol & communication) is a hot and difficult problem in satellite telemetry and telecontrol domain. On the basis of investigating the DS/FH spread spectrum communication systems,key technologies in anti-jam receiver and interference rejection are studied systematically.At the same time the theoretical analysis and simulations are shown in this thesis.The main points are as follows:1,Design a overall structure of anti-jam receiver based on DS/FH.The number of links in satellite telemetry and telecontrol is based on DS/FH, while the design of receiver is the key to improve the anti-jamming capability of TT&C. Whether or not the design for receiver is rationable is directly relative to the distortion of restored signal. The receiver proposed in this paper renders the transmitted signal less susceptible to external Interference, efficiently decreases the distortion of restored signal, and greatly improves the anti-jamming capability.2,design a kind of Long-period sequence spread code.pseudorandom sequence plays a significant role in spread spectrum anti-jamming communication systems. The performance of pseudorandom has the very tremendous influence on the whole system performance. According to practical needs,we design a new kind of Long-period sequence spread code whose operating cycle is longer than a year when the clock rate achieves a 10.23-megahertz. The performance of Long-period sequence spread code is similar to that of the P code,but the operating cycle is longer than that of P code. So it can satisfy the need of satellite tele-control and tele-measure. The experimental result indicates that all the parameters are equal or exceed that of P code.3,Model and simulate the interference signals existing in satellite tele-control and tele-measure channel.The interference of tele-control and tele-measure system stains from various interference platforms,and the interferences from different platforms create different effect on communication. In order to suppress the interferences efficiently, it is necessary to build an suitable environment model. On the basis of investigating the transmission channel of satellite tele-control and tele-measure communication, various kinds of interferences which TT&C instruction might encounter, are analyzed in detail. Based on this, we build the mathematical model of various kinds of interferences,and offers the result of simulation.4,we use computer programming to implement LMS adaptive transversal filter algorithm and Windowed DFT-based transform domain filtered algorithm,and simulate the performance of interference rejection. Aimed at the common Narrowband Interference and Wideband Interference in satellite telemetry and telecontrol, LMS algorithm and DFT algorithm are used to Model and simulate in interference rejection of Narrowband Interference, and to analy the restraint strategy of wideband Interference, respectively.