Signal Processing Circuit Design Based On Embedded System And Research On Anti-chaff Interferenc

Millimeter wave is characterized by high working frequency and strong penetrating ability.Based on this,millimeter wave fuze ranging system owns many relevant advantages,e.g.,all-weather operation,precise ranging,and real time,which are very important in modern war.As one of the most mature passive jamming forms,chaff has always been widely used in the battlefield.Chaff jamming may compromise the distance performance of millimeter wave fuze ranging system seriously,and therefore,it is very important to carry out relevant studies focusing on anti-chaff jamming of millimeter wave fuze.The following are some work the study did concerning millimeter wave distance fuze signal processing,chaff jamming and anti-chaff jamming:1.The overall structure and working principle of millimeter wave linear frequency modulated distance fuze system were analyzed,and relevant parameters of the system were determined according to the design requirements.2.The software for millimeter wave frequency modulated distance fuze signal processing system based on STM32F7 was designed,including intermediate frequency signal acquisition,FIR filter,FFT algorithm and executive level control signal,and etc.The experimental results for the system were good,with small distance error and good real-time performance,and the design requirements were met.The design and making of intermediate frequency amplifier were realized,with gain 18.1dB at 500 KHz,and the amplification of intermediate frequency signal was realized.3.The chaff motion model and echo signal were analyzed.Firstly,the basic characteristics of chaff were investigated,and the principles for selection of relevant parameters were analyzed.A dynamic diffusion model of chaff cloud was established based on an analysis on single chaff trajectory.The scattering electric field of a single chaff was analyzed,and the echo signal modeling for chaff cloud was completed.An anti-chaff jamming method based on FCM algorithm was proposed.An anti-chaff jamming experiment was designed and completed with chaff echo signal stored in the microcontroller and scattering intensity ratio used as the input data set.The experimental results were good.4.A chaff echo database was established.A large number of simulated chaff echo data obtained by simulation were stored by the MySQL WorkBench platform for the convenience of data management and search.At last,an anti-chaff jamming experiment was designed and completed preliminarily using the data in database,with waveform entropy value as the characteristic quantity.