An efficient coherent integration method for RFPA radar signals in high-speed and multi-target scenarios

TY - JOUR

T1 - An efficient coherent integration method for RFPA radar signals in high-speed and multi-target scenarios

AU - Chen, Yijiang

AU - Wei, Guohua

AU - Bai, Jiahao

AU - Wang, Xu

N1 - Publisher Copyright: © 2025 Elsevier Inc.

PY - 2026/3/1

Y1 - 2026/3/1

N2 - Although random frequency and pulse repetition interval (PRI) agile (RFPA) radar signals provide strong electronic counter-countermeasures (ECCM) capabilities, coherent integration under high-speed and multi-target scenarios remains a critical but insufficiently explored challenge. We propose an efficient coherent integration method termed RFPA-KT-NUFFT, which combines Keystone transform (KT) and nonuniform fast Fourier transform (NUFFT). The truncated-sinc-interpolation-based KT exploits low computational complexity to correct range migration and decouple the interdependencies between frequency and PRI. Next, a tailored phase compensation function is developed to harness the frequency-agile bandwidth, thereby enabling high range resolution and facilitating multi-target separation. Finally, NUFFT efficiently handles the nonuniform slow-time sampling for coherent integration. Monte Carlo experiments with a 500-sequence agile waveform library demonstrate that the proposed method significantly reduces runtime while maintaining integration performance comparable to existing optimal methods, offering a viable solution that achieves a favorable trade-off between performance and efficiency in high-speed and multi-target scenarios.

AB - Although random frequency and pulse repetition interval (PRI) agile (RFPA) radar signals provide strong electronic counter-countermeasures (ECCM) capabilities, coherent integration under high-speed and multi-target scenarios remains a critical but insufficiently explored challenge. We propose an efficient coherent integration method termed RFPA-KT-NUFFT, which combines Keystone transform (KT) and nonuniform fast Fourier transform (NUFFT). The truncated-sinc-interpolation-based KT exploits low computational complexity to correct range migration and decouple the interdependencies between frequency and PRI. Next, a tailored phase compensation function is developed to harness the frequency-agile bandwidth, thereby enabling high range resolution and facilitating multi-target separation. Finally, NUFFT efficiently handles the nonuniform slow-time sampling for coherent integration. Monte Carlo experiments with a 500-sequence agile waveform library demonstrate that the proposed method significantly reduces runtime while maintaining integration performance comparable to existing optimal methods, offering a viable solution that achieves a favorable trade-off between performance and efficiency in high-speed and multi-target scenarios.

KW - Coherent integration

KW - Keystone transform

KW - Multi-target

KW - Non-uniform fast fourier transform

KW - Random frequency and pulse repetition interval agile

UR - https://www.scopus.com/pages/publications/105025692900

U2 - 10.1016/j.dsp.2025.105838

DO - 10.1016/j.dsp.2025.105838

M3 - Article

AN - SCOPUS:105025692900

SN - 1051-2004

VL - 171

JO - Digital Signal Processing: A Review Journal

JF - Digital Signal Processing: A Review Journal

M1 - 105838

ER -