volume | PIER Journals

Abstract

Processing over-the-horizon radar (OTHR) signals is challenging due to appearance of several very close components in the time-frequency plane, strong noise and clutter, multipath propagation, and aliasing. We propose a two-stage procedure for estimating multipath signal components from the received mixture. In the first stage, the instantaneous frequency is estimated from the time-frequency representation of the received signal. The random samples consensus algorithm is applied to the instantaneous frequency estimate to improve the robustness of the procedure against various effects in the underlying signals. In the second stage, the MUSIC algorithm is applied to the dechirped and downsampled signal. The effectiveness of the proposed approach is verified using real-life signals.

1. Fabrizio, G. A., High Frequency Over-the-Horizon Radar: Fundamental Principles, Signal Processing, and Practical Applications, Mc-Graw Hill Education, 2013.

2. Lan, H., Y. Liang, Q. Pan, F. Yang, and C. Guan, "An EM algorithm for multipath state estimation in OTHR target tracking," IEEE Transactions on Signal Processing, Vol. 62, No. 11, 2814-2826, 2014.
doi:10.1109/TSP.2014.2318134 Google Scholar

3. Romeo, K., Y. B.-Shalom, and P. Willett, "Detecting low SNR tracks with OTHR using a refraction model," IEEE Transactions on Aerospace and Electronic Systems, Vol. 53, No. 6, 3070-3078, Dec. 2017.
doi:10.1109/TAES.2017.2726918 Google Scholar

4. Thayaparan, T., R. Riddolls, and K. Shimotakahara, "Frequency monitoring system for over-the-horizon radar (OTHR) in Canada," Proc. of IRS, May 2016, DOI: 10.1109/IRS.2016.7497370. Google Scholar

5. Headrick, J. and M. Skolnik, "Over-the-horizon radar in the HF band," Proceedings of the IEEE, Vol. 62, 664-673, Jun. 1974.
doi:10.1109/PROC.1974.9506 Google Scholar

6. Zhang, Y., M. Amin, and G. Frazer, "High-resolution time-frequency distributions for manoeuvring target detection in over-the-horizon radars," IEE Proceedings Radar, Sonar and Navigation, Vol. 150, 299-304, Aug. 2003.
doi:10.1049/ip-rsn:20030672 Google Scholar

7. Wang, G., X.-G. Xia, B. Root, V. Chen, Y. Zhang, and M. Amin, "Manoeuvring target detection in over-the-horizon radar using adaptive clutter rejection and adaptive chirplet transform," IEE Proceedings Radar, Sonar and Navigation, Vol. 150, 292-298, Aug. 2003.
doi:10.1049/ip-rsn:20030700 Google Scholar

8. Ioana, C., Y. Zhang, M. Amin, F. Ahmad, G. Frazer, and B. Himed, "Time-frequency characterization of micro-multipath signals in over-the-horizon radar," Proc. of Radar Conf., May 2012. Google Scholar

9. Djurović, I., S. Djukanović, M. G. Amin, Y. D. Zhang, and B. Himed, "High-resolution time-frequency representations based on the local polynomial Fourier transform for over-the-horizon radars," Proc. of SPIE, Vol. 8361, May 2012, doi: 10.1117/12.919954. Google Scholar

10. Stanković, L. J., I. Djurović, S. Stanković, M. Simeunović, and M. Daković, "Instantaneous frequency in time-frequency analysis: Enhanced concepts and performance of estimation algorithms," Digital Signal Processing, Vol. 35, 1-13, Dec. 2014.
doi:10.1016/j.dsp.2014.09.008 Google Scholar

11. Djurović, I., "A WD-RANSAC instantaneous frequency estimator," IEEE Signal Processing Letters, Vol. 23, No. 5, 757-761, May 2016.
doi:10.1109/LSP.2016.2551732 Google Scholar

12. Djurović, I., "QML-RANSAC: PPS and FM signals estimation in heavy noise environments," Signal Processing, Vol. 130, 142-151, Jan. 2017.
doi:10.1016/j.sigpro.2016.06.022 Google Scholar

13. Sheng, H., Y. Gao, B. Zhu, K. Wang, and X. Liu, "Feature extraction of SAR scattering centers using M-RANSAC and STFRFT-based algorithm," EURASIP Journal on Advances in Signal Processing, Vol. 2016, No. 1, 46, 2016.
doi:10.1186/s13634-016-0345-z Google Scholar

14. Djurović, I. and L. J. Stanković, "An algorithm for the Wigner distribution based instantaneous frequency estimation in a high noise environment," Signal Processing, Vol. 84, 631-643, Mar. 2004.
doi:10.1016/j.sigpro.2003.12.006 Google Scholar

15. Conru, C., I. Djurovic, C. Ioana, A. Quinquis, and L. J. Stanković, "Time-frequency detection using Gabor filter bank and Viterbi based grouping algorithm," Proc. of IEEE ICASSP, 2005. Google Scholar

16. Stanković, L. J., I. Djurović, A. Ohsumi, and H. Ijima, "Instantaneous frequency estimation by using Wigner distribution and Viterbi algorithm," Proc. of IEEE ICASSP, 2003. Google Scholar

17. Djurović, I., "Viterbi algorithm for chirp-rate and instantaneous frequency estimation," Signal Processing, Vol. 91, No. 5, 1308-1314, May 2011.
doi:10.1016/j.sigpro.2010.10.007 Google Scholar

18. Djurović, I. and L. J. Stanković, "STFT-based estimator of polynomial phase signals," Signal Processing, Vol. 92, No. 11, 2769-2774, Nov. 2012.
doi:10.1016/j.sigpro.2012.05.015 Google Scholar

19. Djurović, I. and L. J. Stanković, "Quasi maximum likelihood estimator of polynomial phase signals," IET Signal Processing, Vol. 13, No. 4, 347-359, Jun. 2014.
doi:10.1049/iet-spr.2013.0104 Google Scholar

Dr. Igor Djurovic

Dr. Yimin D. Zhang