| With the vigorous development of China's aerospace industry, the number of satellites in orbit is increasing, the requirements in satellite measurement precision and collaborative is increasing greatly. The existing microwave unified TT&C system show its limitations. The Spread Spectrum TT&C system has already become the future development trend of TT&C. It has good anti-jamming capability, good concealment capability, low probability to be intercepted, and it can be any location. Taking it as the background, the thesis studies the synchronization of Spread spectrum TT&C system, analyzes the slippage correlation acquisition algorithm based on FPGA platform, and put forward solutions proposed to weak high dynamic signal acquisition. Main research results are showed as follow.1. The principle of Spread spectrum TT&C system is studied. Based on the basic theory of spread spectrum technology, the speed, distance, time difference, frequency difference measurement method in the non-coherent mode is derived.2. By comparing three typical methods to capture, it concluded that slippage correlation capture algorithm is able to meet the requirements of the weak high dynamic signal acquisition. It has 32 parallel slip, the integration time is 0.8ms, the normalized threshold is Rg′= 16.8, and the detection probability and false alarm probability are 0.992 and 0.0002, respectively.3. The proposed key technologies are implemented on the FPGA platform for a TT&C transponder. The software is simulated and optimized by using ISE, Chipscope, etc.4. The program is tested and validated by ground test equipment. The result shows that capture time is not more than 6s, acquisition probability exceeds 0.9, and false alarm probability is less than 0.001.
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