The Design And Implementation Of Three Channel MTI Signal Processing

Radar has a wide range of application in aerospace, meteorology, defense, etc. With the continuous progress and development of science and technology, modern radar with higher technology is needed by modern electronic and information warfare. Modern radar is affected by complex natural environment and integrated electronic device interference and other circumstances, which requires us to improve accurate detection and anti-jamming technology in complex environments. At the same time, with the rapid development of information processing technology based on software radio technology, theoretical studies on radar performance is greatly extended; the cost of radar technology research and production have been greatly reduced; the range of applications of radar has been greatly expanded.The signal processing is an important part of the radar system. Combined with the author’s research work, this paper studies Moving Target Indication(MTI), clutter map processing, noncoherent integration processing and Constant False-Alarm Rate(CFAR) processing technology. This paper introduces the design of MTI filter bank based on Least Squares method, staggered MTI filter based on Zero allocation method and shows the frequency response of the filter design. Combined with MATLAB simulation, this paper has a detailed analysis of MTI filter processing and then adaptive MTI processing results are given based on weighting coefficient method. Then the design of three-channel MTI process, workflow, and DSP programming are introduced. Three-channel MTI includes normal channel, ground clutter processing channel and dynamic clutter processing channel. Synthetic guidelines are given about three-channel test results according to engineering practice.The design of workflow describes data transfer between DSPand DSP, FPGA, SDRAM as well as the timing of each module of MTI processing in a single PRT. The interrupt service routine and the main program is introduced in DSP programming. The interrupt service routine contains an external interrupt service routine triggered by FPGA and a DMA interrupt service routine. The interrupt service routine controls the data transmission and the work mode. After the interrupt service routine, the main program completes the digital signal processing according to the work mode. Based on the measured data, this paper shows the comparative results before and after MTI processing, which proves three-channel MTI of practical use in clutter suppression. Finally, the corresponding solution to the two problems in the algorithm is put forward. According the characteristics of DSP assembler instruction, a logarithm operation is achieved by a Maclaurin series decomposition. According to the characteristics of tangent operation, an arctangent operation is achieved by angle range transformation and Chebyshev series decomposition. Both operations have the characteristics of high precision and are easy to achieve.