Design And Analysis On Signal Waveform For LPI Radar

The Low Probability ofIntercept (LPI) technique is one effective way onconter-reconnaissance and anti-jamming for radar. To improve the performance of the LPI radarin conter-reconnaissance and anti-jamming, a design scheme for LPI radar is proposed. Thesignal waveform and its detection are studied. The detection, conter-reconnaissance andanti-jamming performances of the LPI radar are analyzed. The main work consists of thefollowing parts.A design scheme of LPI rarda is proposed. Firstly, the working mcchanism of four typicalradars are analyzed and their advantages and disadvantages are discussed. Based on the idea thatusing camouflage deception signaladopting multi-channel transmitter, selectively receivingwaveform, a scheme for LPI radar is designed.Two signal for the working channel and a signal waveform for the camouflage deceptionchannel are designed, based on the analysis of several typical waveforms forcounter-reconnaisance and anti-jamming. The two working channel signal waveformsrespectively adopt the modulating of the linear frcquency moency dulation withthepseudorandom code phase modulation and the modulating of the frequency agility with thepseudorandom code phase modulation. the The modulation offrequency agility with theoseudorandom code phase modulation and the random plse position modulation is used for thecamouflage deception channel. The time-frequency domain characteristics, the ambiguityfunction of the two working channel signal waveforms are analyzed, and the time-frequencydomain characteristics are analyzed for the camouflage deception signal and the mixedtransmitting signal waveforms of the three channels. The results show that the two workingsignal waveforms approximately”thumbtack” type ambiguity function and better rangeresolution and velocity resolution. The mixed transmitting signal waveform shows clutter andnon-regularity, which makes the radar waveform more deception and complexity.The signal processing technique of LPI Radar is studied. Based on the characteristics of theLPI radar, the methods on waveform selective processing are analyzed. A range measurementmethod using the correlation of code shift is proposed, and the rader range measurcmentaccuracy is improved. The different Doppler frequency tracking algorithms are managed basedon the different frequencies of the LPI radar, and the velocity measurement accuracy isadapted.The counter-reconnaissance and anti-jamming performances of the radar are amalyzed. Theindexes on the performances of counter-reconnaissance and anti-jamming are taken to measurethat of the LPI radar. The computation and simulation results show that the LPI radar has morebetter counter-reconnaissance and anti-jamming performance.