volume | PIER Journals

Abstract

An improved range-Doppler algorithm (RDA) is proposed to reconstruct images from synthetic aperture radar (SAR) data received at high squint angles. At a higher squint angle, a larger synthetic aperture is required to receive sufficient amount of data for image reconstruction, and the range migration also becomes more serious, which demands more computational load and larger memory size. The proposed method can generate better SAR images with less computational load and memory than the conventional RDA, which is verified by simulations.

1. Wang, W., W.-H. Wu, W. Su, R.-H. Zhan, and J. Zhang, "High squint mode SAR imaging using modified RD algorithm," IEEE China Summit Int. Conf. Signal Inform. Process., 589-592, Beijing, China, Jul. 2013.

2. Chen, S., S.-I. Zhang, H.-C. Zhao, and Y. Chen, "A new chirp scaling algorithm for highly squinted missile-borne SAR based on FrFT," IEEE J. Select. Topics Appl. Earth Observ. Remote Sensing, Vol. 8, No. 8, 3977-3987, Aug. 2015.
doi:10.1109/JSTARS.2014.2360192

3. Li, Z.-Y., Y. Liang, M.-D. Xing, Y.-Y. Huai, Y.-X. Gao, L.-T. Zeng, and Z. Bao, "An improved range model and omega-K-based imaging algorithm for high-squint SAR with curved trajectory and constant acceleration," IEEE Geosci. Remote Sensing Lett., Vol. 13, No. 5, 656-660, May 2016.
doi:10.1109/LGRS.2016.2533631

4. Li, W. and J. Wang, "A new improved step transform algorithm for highly squint SAR imaging," IEEE Geosci. Remote Sensing Lett., Vol. 8, No. 1, 118-122, Jan. 2011.
doi:10.1109/LGRS.2010.2053837

5. Wu, Y., G.-C. Sun, X.-G. Xia, M. Xing, J. Yang, and Z. Bao, "An azimuth frequency non-linear chirp scaling (FNCS) algorithm for TOPS SAR imaging with high squint angle," IEEE J. Select. Topics Appl. Earth Observ. Remote Sensing, Vol. 7, No. 1, 213-222, Jan. 2014.
doi:10.1109/JSTARS.2013.2258893

6. An, D.-X., X.-T. Huang, T. Jin, and Z.-M. Zhou, "Extended two-step focusing approach for squinted spotlight SAR imaging," IEEE Trans. Geosci. Remote Sensing, Vol. 50, No. 7, 2889-3000, Jul. 2012.
doi:10.1109/TGRS.2011.2174460

7. Xu, H., J. Gao, and J. Li, "A variable PRF imaging method for high squint diving SAR," Progress In Electromagnetics Research, Vol. 135, 215-229, 2013.
doi:10.2528/PIER12112304

8. Liang, Y., Z.-Y. Li, L. Zeng, M.-D. Xing, and Z. Bao, "A high-order phase correction approach for focusing HS-SAR small-aperture data of high-speed moving platforms," IEEE J. Select. Topics Appl. Earth Observ. Remote Sensing, Vol. 8, No. 9, 4551-4561, Sep. 2015.
doi:10.1109/JSTARS.2015.2459765

9. Ma, C., H. Gu, W.-M. Su, X.-H. Zhang, and C.-Z. Li, "Focusing one-stationary bistatic forward-looking synthetic aperture radar with squint minimisation method," IET Radar Sonar Navig., Vol. 9, No. 8, 927-932, Sep. 2015.
doi:10.1049/iet-rsn.2014.0499

10. Moreira, A., "Real-time synthetic aperture radar (SAR) processing with a new subaperture approach," IEEE Trans. Geosci. Remote Sensing, Vol. 30, No. 4, 714-722, Jul. 1992.
doi:10.1109/36.158865

11. Zeng, T., Y. Li, Z. Ding, T. Long, D. Yao, and Y. Sun, "Subaperture approach based on azimuth-dependent range cell migration correction and azimuth focusing parameter equalization for maneuvering high-squint-mode SAR," IEEE Trans. Geosci. Remote Sensing, Vol. 53, No. 12, 6718-6732, Dec. 2015.
doi:10.1109/TGRS.2015.2447393

12. Huang, P.-P., W. Xu, and S.-Y. Li, "Spaceborne squinted multichannel synthetic aperture radar data focusing," IET Radar Sonar Navig., Vol. 8, No. 9, 1073-1080, Feb. 2015.
doi:10.1049/iet-rsn.2013.0332

13. Chen, J.-A., J.-D. Zhang, X.-Y. Qiu, and X.-W. Tang, "A modified subaperture imaging algorithm for squinted sliding spotlight SAR," IET Int. Radar Conf., Hangzhou, China, Oct. 2015.

14. Cumming, I. G. and F. H. Wong, Digital Processing of Synthetic Aperture Radar Data, Artech House, 2005.

Dr. Po-Chih Chen

Prof. Jean-Fu Kiang