Low Probability Of Intercept Signal Direction Finding Technology

The present of LPI signals brings a new challenge to electronic warfare. The accurate location of source of LPI signals has significant meaning for it. This subject has become one of the hottest issues in radar and communication field.In this paper, the characteristics of common LPI signals are firstly discussed. Most of the LPI signals are low-powered and widebanded. Therefore, the scheme of location should be able to deal with signals with low SNR and wideband, the research starts with enhancing the SNR by using the correlation, and reserving the phase information. Then, several ways of traditional DOA estimation are discussed in detail. Because traditional DOA estimation can only deal with narrowbanded signals and these ways can not deal with coherent signals, so the sheme should be able to deal with coherent signals and widebanded signals in order to estimate accurately. At last, several ways of widebanded DOA estimation are discussed. Not only the low SNR and wideband signals can be estimated accurately, but the coherent signals can also be processed by this sheme.The algorithms in this paper are all simulated and compared. The factors that have impact on accuracy of DOA are also discussed.