Design and Characteristic Analysis of P4-Costas Composite Modulation Signal

The low probability of intercept (LPI) radar waveforms can reduce the effectiveness of enemy electronic interference. Composite modulation signals combine two or more modulation techniques, improving the LPI capability of the signal as well as its resistance to various types of interference. By using frequency and phase composite modulation, the spectrum can be expanded, the power spectral density can be reduced, and the signal can be more difficult to intercept. Current modulation radar waveforms exhibit certain low probability of intercept characteristics, but further improvement and enhancement are needed. This paper designs a radar waveform based on the composite modulation of linear frequency modulation (LFM), P4 code, and Costas code to enhance the LPI performance of radar emissions. Simulation experiments verify that, compared to radar waveforms with LFM and Barker code composite modulation, this new radar waveform performs better in terms of LPI characteristics and also shows improved anti-jamming capability.