Research And Realization Of Jamming Technology Against Pulse Doppler Radar

Pulse Doppler radar is one of the advanced radar systems in modern times, whichuses low side-lobe and high-gain antenna designing, and in the receiving use someanti-jamming technology, such as matching receiver, coherent processing, side-lobecancellation, side-lobe banking and so on, which greatly improves radar anti-jammingcapability and significantly reduce pressing jamming and deception jamming effect.Therefore, the research of jamming pulse Doppler radar and other advanced systemradar is an important issue currently facing.This paper firstly introduces the definition of pulse Doppler radar, analyzes thecharacteristics of three different pulse repetition frequency mode, and then introducesthe composition and characteristics of PD radar. The radar waveform design is thefoundation of the entire radar design, and also is the key, this paper introduces threekinds of waveform design, which meet the wide PD radar waveform design. Thesignal processing technology of PD radar is a very complex process, this paper brieflyintroduces some of these technologies and the engineering realization method. According to the analysis, summed up the difficulty of jamming PD radar.In this paper, the research of the jamming method is carried in the low frequencyand MTD work mode of pulse Doppler radar. In this mode, radar transmits linear freq-uency modulation signal to improve range resolution and velocity resolution in thecase of limited transmit power. According to LFM signal, the time delay of repeaterjamming, shift frequency jamming, noise convolution jamming and interrupted-sampling jamming are proposed and studied, and their respective advantages anddisadvantages are analyzed by the result of simulations, and then the improvementschemes are proposed. In the actual combat, single point source interference often donot receive optimal jamming effect, therefore, the two source or multiple pointsources jamming scheme of coordination are used, this paper studies some kinds ofmultiple point source jamming methods.In recent years, as the development of the FPGA and other programmable logicdevices, radar signal processing widely uses the programmable logic devices toimprove the processing speed. Because of the great advantages of FPGA in digitalsignal processing, a jamming signal modulation module as the core of an FPGA-basedis designed and finished. Using VHDL hardware description language, the delay transmit jamming, convolution jamming and interrupted-sampling repeater jammingprogramming are completed and then FPGA simulation is proposed by QuartusII ownsimulation tool, its result and expected results which got by Matlab were compared,the result of comparison shows that the FPGA design are close to the expected results,so the algorithm is correct which can generate jamming signal based on FPGA, andachieve the design objective.