Research On Anti-interference Technology And Miniaturized Circuit Design Of Frequency Modulation Ranging Fuz

The radio fuze can control the explosive point of the missile,and it is becoming more and more implacable in information warfare.The LFM fuze has the advantages of simple structure,low cost,and miniaturization.It has been concerned a lot by researchers.According to a specific project’s demand for a miniaturized fuze with anti-information jamming capability,this article researched the anti-jamming technology of LFM fuze and designs the signal processing circuit of miniaturized LFM fuze.Firstly,this paper researched the short-range detection technology of LFM fuze.The velocity measurement method uses the time-domain under-sampling method,and the height measurement method uses Doppler frequency to correct the difference frequency and then deduces the missile height.The simulation results show that the velocity measurement error is less than 2m/s,the height measurement error is less than 0.1m,and the fuze can output a start signal at a preset height of 10 m.Secondly,aiming at the blanketing jamming of noise amplitude modulation interference,the fractional domain filter algorithm based on the Fractional Fourier Transform is proposed.The signal to jamming ratio required for the missile “misfire” before anti-jamming is-8.2d B,the signal to jamming ratio after adopting the anti-jamming method is-19.2d B,indicating that the fractional domain filter algorithm can effectively combat blanketing jamming.Thirdly,aiming at the problem that sawtooth FM interference,fixed false target forwarding interference,and interval forwarding interference can deceive the fuze to make the missile "explode early",the increased rate detection algorithm is proposed.The simulation shows that the above interference cannot meet the increased rate detection,and the missile no longer "explode early".The ground target echo can meet the increased rate detection so that the fuze can output the start signal correctly,which shows that the increased rate detection can effectively combat deceptive jamming.Fourthly,the signal processing hardware and software of the miniaturized fuze are designed.We drew the circuit board,processed and debugged it.The final PCB has a diameter of only 35 mm and a height of only 24 mm.Based on the Verilog HDL language,the functions of fractional domain filtering,quadrature demodulation,velocity & height measurement,amplitude extraction,and explosion control are implemented.Which makes the fuze designed in this paper have a short-range detection function and electronic counter-countermeasures ability.Finally,this paper built a fuze countermeasure experiment platform for semi-physical simulation and completed the ground target echo experiment,anti-deceptive jamming experiment,and anti-blanketing jamming experiment.The experimental results further verify the effectiveness and feasibility of the anti-jamming method proposed in this paper.