The Transmitting Systme Design Of Distributed Radar Target Information

Netted distributed radar is a new radar system in response to the “modern four threats” like electronic interference, anti-radiation missile etc. It is born under the trends of military electronic equipment becoming systematic and integrative. The radar in net does not only keep its own feature, but also can show systematic effect by sharing information resources. But when the radar in net sends data to the data processing center, the signal will be disturbed and fade for the native noise of the channel and surrounding interference. Therefore, to ensure reliable and efficient transmitting between the single radar in net and the center is a key problem.The distributed radar net with multiple transceiver stations and one data processing center will be discussed, and the reliable communicating method and anti-jamming technology will be further researched in this thesis. A FPGA design scheme of transmission system between the dots of radar net and the center will be proposed to realize the researched method. The main work is as follows:1. study the commonly used methods of frame synchronization, and choose the appropriate detecting method and parameters according to the data structure of this design. Then the FPGA design and simulation are given.2. In-depth understanding of the technology to keep information transmission reliable and the theory of error control coding. After deep study the convolution coding and Viterbi decoding, the parameter of convolution code like constraint length, rate of encoding and backtracking depth is determined according to the subject needs. Then the design and simulation based on FPGA are shown3. the study of the principles, features, system model of spread spectrum communication is Completed. The common pseudo-random code is also in analysis and comparison. The direct sequence spread spectrum system is the key part of this paper. After study of the spectrum communication synchronization and minimum shift keying(MSK) modulation and demodulation, the DSS system design and simulation based on FPGA is finished.4. We use the Simulink to build the transmitting system and do analysis and simulation of sub model. The anti-interference performance of convolution code and DSS system is the key research. When analysis is finished, we use the Verilog, QuartussII9.0 to design the system and sub model. At last the simulation of design will be given on Modelsim. We compare the simulation result with the Simulink result to verify the feasibility and correctness of the project.