分布式小衛(wèi)星合成孔徑雷達(dá)三維地形成像的最優(yōu)垂直軌跡基線
The Optimal Across-Track Baseline of Distributed Small Satellites Synthetic Aperture Radar for Terrain Elevation Measurement
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摘要: 分布式小衛(wèi)星合成孔徑雷達(dá) (DSS-SAR)中垂直軌跡基線和沿軌跡基線同時(shí)存在、相互耦合，且具備多個(gè)基線，因此與單星SAR干涉相比，DSS-SAR三維地形成像最優(yōu)垂直軌跡基線的確定更為復(fù)雜。該文提出了一種確定DSS-SAR三維地形成像最優(yōu)垂直軌跡基線的新方法。該方法根據(jù)DSS-SAR干涉復(fù)圖像對(duì)的相位差的統(tǒng)計(jì)特性，推導(dǎo)了DSS-SAR多基線干涉的干涉相位的克拉美-羅界，并由此求得測(cè)高誤差與垂直軌跡基線之間的關(guān)系式，令測(cè)高誤差對(duì)垂直軌跡基線的導(dǎo)數(shù)為零，得出DSS-SAR三維地形成像的最優(yōu)垂直軌跡基線。最后根據(jù)最優(yōu)垂直軌跡基線的計(jì)算式，詳細(xì)分析并推導(dǎo)了由3顆小衛(wèi)星構(gòu)成的不同空間編隊(duì)構(gòu)形DSS-SAR的最優(yōu)垂直軌跡基線，結(jié)果表明，當(dāng)基線數(shù)為1時(shí)，論文推導(dǎo)的DSS-SAR多基線干涉最優(yōu)垂直軌跡基線與已有單星SAR干涉最優(yōu)基線設(shè)計(jì)結(jié)果一致。此分析結(jié)果驗(yàn)證了論文方法的正確性。
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關(guān)鍵詞:
- 分布式小衛(wèi)星;SAR;最優(yōu)基線;編隊(duì)構(gòu)形
Abstract: In distributed small satellites-synthetic aperture radar (DSS-SAR), the correlation of echoes is determined by both across-track and along-track baselines which are coupling, and the multi-baseline interferometry is obtained with multi small satellites SAR images. The optimal across-track baseline of DSS-SAR for terrain elevation measurement is more complicatedly determined than that of conventional SAR interferometry. A novel approach is presented in this paper to determine the optimal across-track baseline of DSS-SAR multi-baseline interferometry. On the basis of the statistical characteristics of phase difference of complex SAR image pair, the DSS-SAR interferometric phase estimation Crammer-Rao bound is deduced. The relationship between terrain height accuracy and across-track baseline is presented from the bound. And then the optimal across-track baseline is derived via derivative calculation. Finally, the optimal across-track baseline in different DSS-SAR configuration with three small satellites is calculated and analyzed. It is showed that the optimal baseline of single across-track baseline interferometry according to this paper is in agreement with that from known single satellite SAR interferometry. The result validates the novel approach proposed by this paper. -
Massonnet D. Capabilities and limitations of the interferometric cartwheel[J].IEEE Trans. on Geoscience and Remote Sensing.2001,39(3):506-[2]Rodriguez E, Martin J M. Theory and design of interferometric synthetic aperture radars. IEE Proc.-F, 1992, 139(2): 147.159.[3]徐華平, 周蔭清, 李春升. 星載干涉SAR中的基線問(wèn)題. 電子學(xué)報(bào), 2003, 31(3): 437439. .[4]Li F K, Goldstein R M. Studies of multibaseline spaceborne interferometric synthetic aperture radars. IEEE Trans. on Geoscience and Remote Sensing, 1990, 28(1): 8896. .[5]Just D, Bamler R. Phase statistics of interferograms with applications to synthetic aperture radars. Applied Optics, 1994, 33(20): 43614368. .[6]徐華平. 分布式小衛(wèi)星合成孔徑雷達(dá)理論與方法研究. [博士位論文], 北京:北京航空航天大學(xué)研究生院，2003年.[7]Lee J S, Hoppel K W, et al.. Intensity and phase statictics of multilook polarimetric and interferometric SAR imagery. IEEE Trans. on Geoscience and Remote Sensing, 1994, 32(5): 10171027. .[8]Lombardo P, Lombardini F. Multi-baseline SAR interferometryfor terrain slope adaptivity. Proceedings of IEEE 1997 National Radar Conference, Syracuse, NY, U.S.A., 1997: 196.201.[9]范特里斯H L著, 毛士藝, 周蔭清, 張其善譯. 檢測(cè)、估計(jì)和調(diào)制理論, 卷I, 檢測(cè)、估計(jì)和線性調(diào)制理論[M]. 北京：國(guó)防工業(yè)出版社, 1983: 72.84.[10]Fiedler H, Krieger G, et al.. Analysis of multistatic configurations for spaceborne SAR interferometry[J].IEE Proc.-Radar Sonar Navig.2003, 150(3):87- -
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