Inter-pulse amplitude-frequency-phase agile design for cognitive radar

• Published in: Signal processing Vol. 223; p. 109557
• Main Authors: Li, Yin, Yu, Xianxiang, Fan, Tao, Wang, Wenmin, Wu, Yuanhao, Cui, Guolong, Kong, Lingjiang
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.10.2024
• Subjects: Amplitude-frequency-phase agile design; Cognitive radar; Coordinate descent (CD); Doppler sidelobe level; Coordinate descent (CD); Cognitive radar; Doppler sidelobe level; Amplitude-frequency-phase agile design
• ISSN: 0165-1684
• DOI: 10.1016/j.sigpro.2024.109557

This article deals with the joint design of inter-pulse amplitude, phase and frequency to detect coexisting strong and weak targets in the presence of interference for cognitive radar. First, an amplitude–frequency-phase agile (AFPA) signal model and the corresponding coherent processing method based on phase compensation and non-uniform discrete Fourier transform (NUDFT) are developed. Then, two waveform design criteria, namely the weighted integrated sidelobe level (WISL) and weighted peak sidelobe level (WPSL), are considered to reduce the high sidelobe level in Doppler domain. The waveform is subject to peak-to-average ratio (PAR) constraint to align with current hardware specification, as well as spectrum and signal-to-noise ratio (SNR) loss constraints to enhance interference suppression capabilities. Subsequently, two polynomial-time iterative optimization algorithms are proposed for each of the resulting two non-convex problems. One integrates coordinate descent (CD) and first-order Taylor expansion convex approximation (FTECA), while the other incorporates CD and alternating direction method of multipliers (ADMM), thus updating frequency code and amplitude-phased code alternatively. Finally, numerical simulations demonstrate that the proposed method exhibits significantly better detection performance in the scenario where strong targets are accompanied by weak targets compared to the compressive sensing (CS) approach. •Inter-pulse amplitude, frequency and phase agile waveform.•Inter-pulse agile design via CD-FTECA algorithm for minimizing WISL.•Developing a CD-ADMM framework to track the non-convex problem of minimizing WPSL.