A phase unwrapping method based on phase quality fusion estimation and information filtering

doi:10.11947/j.AGCS.2024.20230247.

Abstract

Abstract:

The LuTan-1 (LT-1) L-band differential interferometric synthetic aperture radar (SAR) system is China's first fully polarized L-band civil SAR satellite constellation, which will extensively monitor and supervise natural resources.One of the main tasks of this satellite constellation is producing a digital elevation model (DEM). As we all know, phase unwrapping is one of the key factors affecting the accuracy of DEM inversion.However, the low accuracy of unwrapping results in areas with high noise and large gradient changes has always been a bottleneck for phase unwrapping. To address the problem, this paper proposes an iterative approach for information filtering and unwrapping that uses the phase quality fusion strategy. First, the coherence, phase gradient, noise component, and interferometric fringe edge of the interferogram are estimated and fitted to guide the unwrapping path to improve the precision of the PU result. Then, during the iteration process, a central differential information filter is used to obtain quasi-real-time state estimation of the unwrapped phase, improving the PU model's robustness. Finally, experimental verification was conducted through TerraSAR-X/TanDEM-X binary star and LT-1 A/B binary star SAR data, and the results showed that the proposed PU approach in this paper is approximately 65.3% more accurate than the statistical cost flow algorithm and about 13.6% more accurate than the unscented information filter unwrapping algorithm. In addition, the experimental results not only confirm the effectiveness of the proposed method but also demonstrate that the LT-1 helix bistatic formation can achieve the expected results for high-precision terrain reconstruction, providing a high-precision data source for the generation of DEM products covering the cloudy and rainy regions of China.

Key words: LuTan-1, DEM, phase unwrapping, phase quality estimation, information filtering

CLC Number:

P237

Yandong GAO, Nanshan ZHENG, Yansuo ZHANG, Shijin LI, Huachao YANG, Hefang BIAN, Qiuzhao ZHANG, Shubi ZHANG, Yu TIAN. A phase unwrapping method based on phase quality fusion estimation and information filtering[J]. Acta Geodaetica et Cartographica Sinica, 2024, 53(10): 1910-1919.

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References 28

[1]	唐新明, 李世金, 李涛, 等. 全球数字高程产品概述[J]. 遥感学报, 2021, 25(1):167-181.
	TANG Xinming, LI Shijin, LI Tao, et al. Review on global digital elevation products[J]. National Remote Sensing Bulletin, 2021, 25(1):167-181.
[2]	李涛, 唐新明, 高小明, 等. SAR卫星业务化地形测绘能力分析与展望[J]. 测绘学报, 2021, 50(7):891-904. DOI:. doi: 10.11947/j.AGCS.2021.20200199
	LI Tao, TANG Xinming, GAO Xiaoming, et al. Analysis and outlook of the operational topographic surveying and mapping capability of the SAR satellites[J]. Acta Geodaetica et Cartographica Sinica, 2021, 50(7):891-904. DOI:. doi: 10.11947/j.AGCS.2021.20200199
[3]	CAI Yonghua, WANG R, YU Weidong, et al. An advanced approach to improve synchronization phase accuracy with compressive sensing for LT-1 bistatic spaceborne SAR[J]. Remote Sensing, 2022, 14(18):4621.
[4]	李涛, 唐新明, 李世金, 等. L波段差分干涉SAR卫星基础形变产品分类[J]. 测绘学报, 2023, 52(5):769-779. DOI:. doi: 10.11947/j.AGCS.2023.20220050
	LI Tao, TANG Xinming, LI Shijin, et al. Classification of basic deformation products of L-band differential interferometric SAR satellite[J]. Acta Geodaetica et Cartographica Sinica, 2023, 52(5):769-779. DOI:. doi: 10.11947/j.AGCS.2023.20220050
[5]	高延东, 卞正富, 张书毕, 等. 自适应局部梯度估计平滑UKF相位解缠算法[J]. 中国矿业大学学报, 2022, 51(5):1007-1015.
	GAO Yandong, BIAN Zhengfu, ZHANG Shubi, et al. Adaptive local gradient estimation smoothing UKF phase unwrapping algorithm[J]. Journal of China University of Mining & Technology, 2022, 51(5):1007-1015.
[6]	YU Hanwen, LAN Yang, YUAN Zhihui, et al. Phase unwrapping in InSAR: a review[J]. IEEE Geoscience and Remote Sensing Magazine, 2019, 7(1):40-58.
[7]	XU Gang, GAO Yandong, LI Jinwei, et al. InSAR phase denoising: a review of current technologies and future directions[J]. IEEE Geoscience and Remote Sensing Magazine, 2020, 8(2):64-82.
[8]	GHIGLIA D C, PRITT M D. Two-dimensional phase unwrapping: theory, algorithms, and software[M]. New York: Wiley, 1998.
[9]	肖枫, 伍吉仓, 刘朝功, 等. 不同质量图在相位解缠算法中的比较分析[J]. 大地测量与地球动力学, 2010, 30(2):80-85.
	XIAO Feng, WU Jicang, LIU Chaogong, et al. Comparison among different quality maps used for phase unwrapping[J]. Journal of Geodesy and Geodynamics, 2010, 30(2):80-85.
[10]	WANG Hai, HU Jun, FU Haiqiang, et al. A novel quality-guided two-dimensional InSAR phase unwrapping method via GAUNet[J]. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2021, 14:7840-7856.
[11]	BIOUCAS-DIAS J M, VALADÃO G. Phase unwrapping via graph cuts[J]. IEEE Transactions on Image Processing, 2007, 16(3):698-709.
[12]	COSTANTINI M. A novel phase unwrapping method based on network programming[J]. IEEE Transactions on Geoscience and Remote Sensing, 1998, 36(3):813-821.
[13]	CHEN C W, ZEBKER H A. Two-dimensional phase unwrapping with use of statistical models for cost functions in nonlinear optimization[J]. Journal of the Optical Society of America A, 2001, 18(2):338-351.
[14]	KRAMER R, LOFFELD O. Phase unwrapping for SAR interferometry with Kalman filtering[C]//Proceedings of 1996 EUSAR Conference. Berlin: VDE-Verlag Gmbh, 1996.
[15]	LOFFELD O, KRAMER R. Local slope estimation and Kalman filtering[C]//Proceedings of 1996 PIERS. Innsbruck: PIERS, 1996.
[16]	KRAMER R, LOFFELD O. Presentation of an improved phase unwrapping algorithm based on Kalman filters combined with local slope estimation[C]//Proceedings of the “Fringe 96” Workshop on ERS SAR Interferometry. Zurich: [s.n.], 1997.
[17]	XIE Xianming, PI Yiming. Phase noise filtering and phase unwrapping method based on unscented Kalman filter[J]. Journal of Systems Engineering and Electronics, 2011, 22(3):365-372.
[18]	GAO Yandong, WANG Guanghui, WANG Geng, et al. Two-dimensional phase unwrapping method using a refined D-LinkNet-based unscented Kalman filter[J]. Optics and Lasers in Engineering, 2022, 152:106948.
[19]	YU Hanwen, LAN Yang. Robust two-dimensional phase unwrapping for multibaseline SAR interferograms: a two-stage programming approach[J]. IEEE Transactions on Geoscience and Remote Sensing, 2016, 54(9):5217-5225.
[20]	XU Wei, CHANG E C, KWOH L K, et al. Phase-unwrapping of SAR interferogram with multi-frequency or multi-baseline[C]//Proceedings of 1994 IEEE International Geoscience and Remote Sensing Symposium. Pasadena: IEEE, 1994: 730-732.
[21]	PASCAZIO V, SCHIRINZI G. Multifrequency InSAR height reconstruction through maximum likelihood estimation of local planes parameters[J]. IEEE Transactions on Image Processing, 2002, 11(12):1478-1489.
[22]	MAO Wenfei, LIU Guoxiang, WANG Xiaowen, et al. Using range split-spectrum interferometry to reduce phase unwrapping errors for InSAR-derived DEM in large gradient region[J]. Remote Sensing, 2022, 14(11):2607.
[23]	MORISHITA Y. Effective unwrapping of complicated phases by exploiting multiple interferograms: a case study of the 2016 Kumamoto earthquake[J]. Earth Planets and Space, 2022, 74(1):33.
[24]	周立凡, 张世奇, 夏瑜, 等. 基于间断自适应MRF的相位解缠算法[J]. 测绘通报, 2020(12):6-10.
	ZHOU Lifan, ZHANG Shiqi, XIA Yu, et al. Phase unwrapping method based on discontinuity adaptive Markov random fields[J]. Bulletin of Surveying and Mapping, 2020(12):6-10.
[25]	SPOORTHI G E, GORTHI R K S S, GORTHI S. PhaseNet 2.0: phase unwrapping of noisy data based on deep learning approach[J]. IEEE Transactions on Image Processing, 2020, 29:4862-4872.
[26]	ZHOU Lifan, YU Hanwen, LAN Yang. Deep convolutional neural network-based robust phase gradient estimation for two-dimensional phase unwrapping using SAR interferograms[J]. IEEE Transactions on Geoscience and Remote Sensing, 2020, 58(7):4653-4665.
[27]	崔海华, 廖文和, 程筱胜, 等. 相位展开算法中质量权值的数学描述与分析[J]. 光学学报, 2010, 30(1):97-104.
	CUI Haihua, LIAO Wenhe, CHENG Xiaosheng, et al. Mathematic descriptions and analysis of quality weighting factors in phase unwrapping algorithms[J]. Acta Optica Sinica, 2010, 30(1):97-104.
[28]	XIE Xianming, DAI Gaoxing. Unscented information filtering phase unwrapping algorithm for interferometric fringe patterns[J]. Applied Optics, 2017, 56(34):9423-9434.