Algorithm Design And Hardware Implementation Of Weak Target Detection

Microwave radar has attracted extensive attention in the security market for its unique advantages,such as strong adaptability and low cost.However,the echo signal of low signal-to-noise ratio,which caused by the low radiated power and the strong background noise,brings great difficulties to radar detection and early warning.According to the actual situation of the detection of security radar,the following work has been done based on the detection of the weak target.1?In order to solve the problem of weak target echo signal in security radar,two solutions including twice mixing and long-term accumulation are used in the paper.As for the former,the advantages and disadvantages of homodyne receiver and super heterodyne receiver are compared and analyzed.An improved radar system structure is designed,which improves the sensitivity of LFMCW radar.2?The mechanism of radar weak target migrating through resolution cell(MTRC)caused by long-term integration is analyzed theoretically in the paper.Degradation in accumulation performance due to MTRC is solved by an algorithm based on Keystone transform.For the engineering problems of multi-objective and multi-ambiguities,the distance compensation algorithm based on Keystone transform is further improved,making it suitable for target detection in multi-target situations.3?On the basis of the application background of the system,the design parameter and frame diagram of the weak target detection system are put forward,and the signal processing board of the system is designed and developed.The debugging and testing of each module of the signal processing board have been completed,and the weak target detection algorithm on board is realized.4?The weak target detection system is verified through the experiment platform.The measured data of the traditional LFMCW radar system and the improved radar system are analyzed and compared.It is proved that the system structure put forward in this paper improves the sensitivity of the radar.Meanwhile,this paper validates the direct MTD detection algorithm and the MTD detection algorithm based on Keystone transform.The experimental results show that the MTD detection algorithm based on Keystone transform can improve the detection ability of weak targets.