The Study Of Terminal-Guided Radar Detectors In Anti-Ship Missile

During a scan of pulsed scanning radar, the returns are a train of pulses modulated by the antenna beam shape which is normally referred to as antenna beam-shape loss, therefore the radar detection performance is reduced. To use all energy of target returns, non-coherent(video) integration is often implemented after the envelope detector to improve the radar sensitivity. The optimum integration weighting is proportional to antenna gain.Radar detectors (integrators) can accomplish pulsed integration and are commonly employed in terminal guided radar of anti-ship missile. Some detectors which are commonly put into practice are firstly analyzed with their fundamentals, detection capability, stability and angular accuracy and then the realization of these detectors are presented. A new discrete method is provided to get the approximation PDF of system output because the output PDF is difficultly obtained when a linear shift invariant system is excited with noise only. So, the detection threshold can be easily obtained on the basis of the PDF of output system.To improve the performance of radar integration, a novel tri-pole filter is proposed as a video integrator which is implemented using parallel form structure because of its faster running and less integration error than other structures. The genetic algorithm (GA) is a stochastic searching method which provides global search capability and avoids local minima problem. Coefficients optimization of tri-pole filter is accomplished using GA in order that the tri-pole filter's impulse response can approximate optimum weighting. A new fitness function in time domain is presented which is used to evaluate the similarity between the impulse response of tri-pole filter and optimum integration weighting. Consequently, the design of IIR filter in time domain is realized using this fitness function.For the sake of needs of comparison with output SNR in different radar detectors, a unitized output SNR definition is introduced and a formula through which the output variance of IIR filter can be calculated is presented. Subsequently, the theoretical analysis results of all radar detectors are given...