Sar Calibration: An Overview

IEEE Transactions on Geoscience and Remote Sensing

Volumn 30, Issue 6, 1992, Pages 1107-1121

  Freeman, Anthony ^a  

^a CALIFORNIA INSTITUTE OF TECHNOLOGY   (United States)

Author keywords

calibration; image quality polarimetrv; interferometry; SAR

Indexed keywords

EID: 84947662402     PISSN: 01962892     EISSN: 15580644     Source Type: Journal    
DOI: 10.1109/36.193786     Document Type: Article

References (127)

1. C. A. Wiley, “Pulsed doppler radar methods and apparatus,” U.S. Patent 3,196,436, filed Aug. 13, 1954, patented July 20, 1965.
2. W. T. K. Johnson, “Magellan Imaging Radar Mission to Venus,” Proc. IEEE, Vol. 79, No. 6, pp. 777–790, June 1991.
3. E. P. W. Attema, “The Active Microwave Instrument On-Board the ERS-1 Satellite,” Proc. IEEE, Vol. 79, No. 6, pp. 791–799, June 1991.
4. Y. Nemoto, H. Nishino, M. Ono, H. Mizutamari, K. Nishikawa, and K. Tanaka, “Japan Earth Resources Satellite-1 Synthetic Aperture Radar,” Proc. IEEE, Vol. 79, No. 6, pp. 800–809, June 1991.
5. R. L. Jordan, B. L. Huneycutt, and M. Werner, “The SIR-C/X-SAR Synthetic Aperture Radar System,” Proc. IEEE, Vol. 79, No. 6, pp. 827–838, June 1991.
6. R. K. Raney, A. P. Luscombe, E. J. Langham, and S. Ahmed, “RADARSAT,” Proc. IEEE, Vol. 79, No. 6, pp. 839–849, June 1991.
7. C. Elachi, E. Im, L. E. Roth, and C. L. Werner, “Cassini Titan Radar Mapper,” Proc. IEEE, Vol. 79, No. 6, pp. 867–880, June 1991.
8. J. P. Ford et al., “Seasat views North America, the Caribbean and Western Europe with imaging radar,” JPL pub. no. 80–67, Nov. 1980.
9. A. Freeman, T. C. Curlander, P. D. Dubois, and J. D. Klein, “SIR-C Calibration Workshop Report,” JPL Center for Radar Studies pub. no. 88–003, JPL Pub. # D-6165, Nov. 1988.
10. F. T. Ulaby, R. K. Moore, and A. K. Fung, Microwave Remote Sensing: Active and Passive, Vol. ’s I, II and III. Reading, MA: Addison-Wesley, 1981–1989.
11. F. T. Ulaby and C. Elachi, Eds., Radar Polarimetry for Geoscience Applications.Norwood, MA: Artech House, 1990.
12. R. K. Raney, “SAR response to partially coherent phenomena,” IEEE Trans. Antennas Propagat., Vol. AP-28, 777–787, Nov. 1980.
13. R. K. Raney, “Transfer functions for partially coherent SAR systems,” IEEE Trans. Aerosp. Electron. Syst., Vol. AES-19, No. 5, pp. 740–749, Sept. 1983.
14. R. K. Moore, “Tradeoff between picture element dimensions and Noncoherent Averaging in Side-looking Airborne Radar,” IEEE Trans. Aerosp. Electron. Syst., Vol. AES-15, No. 5, pp. 697–708, Sept. 1979.
15. F-K. Li, C. Croft, and D. N. Held, “Comparison of Several Techniques to obtain Multiple-look SAR imagery,” IEEE Trans. Geosci. Remote Sensing, vol. GE-21 no. 3, 370–375, July 1983.
16. J. S. Zelenka, “Comparison of continuous and discrete mixed-integrator processors,” J. Opt. Soc. Amer., Vol. 66, No. 11, pp. 1295–1304, Nov. 1976.
17. J. S. Lee, “Speckle suppression and analysis of Synthetic Aperture Radar images,” Opt. Eng., Vol. 25, No. 5, pp. 636–643, May 1986.
18. J. S. Lee, M. R. Grunes, and S. A. Mango, “Speckle reduction in multipolarization, multifrequency SAR imagery,” IEEE Trans. Geosci. Remote Sensing, vol. 29, pp. 535–544, July 1991.
19. A. Moreira, “Improved multilook techniques applied to SAR and SCANSAR imagery,” IEEE Trans. Geosci. Remote Sensing, vol. 29, pp. 529–534, July 1991.
20. EOS SAR Instrument Panel Report, NASA publication, 1988.
21. J. D. Lyden, B. A. Burns and A. L. Maffett, “Characterization of sea-ice types using synthetic aperture radar,” IEEE Trans. Geosci. Remote Sensing, Vol. GE-22, No. 5, pp. 431–439, Sept. 1984.
22. J. C. Curlander, B. Holt, and K. J. Hussey, “Determination of sea-ice motion using digital SAR imagery,” IEEE Trans. Oceanic Eng., vol. OE-10, pp. 358–367, Oct. 1985.
23. F. Leberl et al. “SIR-B stereo-radargrammetry of Australia,” Int. J. Remote Sensing, Vol. 9, No. 5, pp. 997–1012, May 1988.
24. R. M. Goldstein and A. K. Gabriel, “Crossed orbit interferometry: Theory and experimental results from SIR-B,” Int. J. Remote Sensing, Vol. 9, No. 5, pp. 857–872, May 1988.
25. R. Kwok, private communication.
26. P. D. Dubois et al., “SIR-C science calibration requirements,” Proc. IGARSS ’89 (Vancouver, BC), Canada, July 1989.
27. R. K. Raney, “Synthetic aperture imaging radar and moving targets,” IEEE Trans. Aerosp. Electron. Syst., vol. AES-7, pp. 499–505, May 1971.
28. W. M. Brown, “Synthetic Aperture Radar,” IEEE Trans. Aerosp. Electron. Syst., vol. AES-3, pp. 217–229, Mar. 1967.
29. J. H. Mims and J. L. Farrell, “Synthetic aperture imaging with maneu-vers,” IEEE Trans. Aerosp. Electron. Syst., vol. AES-8, pp. 410–418, July 1972.
30. J. C. Kirk, Jr., “Motion compensation for synthetic aperture radar,” IEEE Trans. Aerosp. Electron. Syst., Vol. AES-11, pp. 338–348 May 1975.
31. S. Quegan, “Interpolation and sampling in SAR images,” IEEE Trans Geosci. Remote Sensing, Vol. 28, July 1990.
32. S. Quegan and J. Lamont, “Ionospheric and tropospheric effects on synthetic aperture radar performance,” Int. J. Remote Sensing, vol. 7, no. 4, pp. 525–539, 1986.
33. A. Freeman, “Calibration and image quality assessment of the NASA/JPL Aircraft SAR during Spring 1988,” JPL Pub. #D-7197, Feb. 1990.
34. S. Bruzzi, J. P. Guignard, and T. K. Pike, “Quality assessment of remote-sensing data: The SAR case,” ESAJ., vol. 6, pp. 271–279, 1982.
35. R. H. Mitchel and S. Marder, “SAR image quality considerations,” Opt. Eng., Vol. 21, No. 1, Jan./Feb. 1982.
36. G. E. Keyte and M. J. Pearson, “An assessment of Seasat-SAR image “” quality, in satellite microwave remote sensing,” T. D. Allan, Ed. England: Ellis Norwood, 1983, ch. 11, pp. 187–209.
37. M. R. B. Forshaw, A. Haskell, P. F. Miller, D. J. Stanley, and J. R. G. Townshend, “Spatial resolution of remotely sensed imagery: A review paper,” Int. J. Remote Sensing, vol. 4, no. 3, pp. 497–520, 1983.
38. T. K. Pike, “SAR image quality: A review,” DFVLR Rep. 85–07, 1985.
39. “SAR Data Quality Assessment and Rectification,” Final Rep., vol. 2, GEC-Marconi Research Laboratories, under ESA contract # 6635/86/HGE-I, Mar. 1988.
40. S. Quegan, “Measurement of geometric distortion in airborne SAR images,” Proc. IGARSS ’84 (Strasbourg, France), Aug. 27–30, pp. 595–599, 1984.
41. D. Blacknell, A. Freeman, R. G. White, and J. W. Wood, “The prediction of geometric distortion in airborne SAR imagery from autofocus measurements,” IEEE Trans. Geosci. Remote Sensing, vol. GE-25, pp. 775–782, Nov. 1987.
42. D. Blacknell, A. Freeman, S. Quegan, I. A. Ward, I. P. Finley, C. J. Oliver, R. G. White, and J. W. Wood, “Geometric accuracy in airborne SAR images,” IEEE Trans. Aerosp. Electron. Syst., Vol. 25, No. 2, pp. 241–258, Mar. 1989.
43. S. M. Madsen and S. Pang, “Improved geometric calibration for SIR-C data,” Proc. IGARSS ’91 (Espoo, Finland), June 1991.
44. S. M. Madsen, “Speckle Theory: Modeling, analysis and applications related to synthetic aperture radar data,” Ph.D. thesis LD 62, Electromagnetics Institute, Technical University of Denmark, Lyngby, 1986.
45. J. W. Goodman, “Statistical properties of laser speckle patterns,” in Laser Speckle and Related Phenomena (vol. 9 of Topics in Applied Physics), J. C. Dainty, Ed. New York & Berlin: Springer Veflag 1975.
46. A. Freeman and J. C. Curlander, “Radiometric correction and calibration of SAR images,” Photogrammetr. Eng. and Remote Sensing, Vol. 55, No. 9, pp. 1295–1301, Sept. 1989.
47. N. C. Currie, Ed., Techniques of Radar Reflectivity Measurement. Norwood, MA: Artech House, 1984.
48. P. Hoogeboom, P. Binnenkade, and L. M. M. Veugen, “An algorithm for radiometric and geometric correction of digital SLAR DATA,” IEEE Trans. Geosci. Remote Sensing, vol. GE-22, pp. 570–576, 1984.
49. S. D. Wall and J. C. Curlander, “Radiometric calibration analysis of SIR-B imagery,” Int. J. Remote Sensing, Vol. 9, No. 5, pp. 891–906, May 1988.
50. R. W. Larson, P. L. Jackson, and E. S. Kasischke, “A digital calibration method for synthetic aperture radar systems,” IEEE Trans. Geosci. Remote Sensing, vol. 26, pp. 753–763, Nov. 1988.
51. R. W. Larson, D. T. Politis, and J. L. Walker, “SAR calibration: A technology review,” in Radar Calibration, Proc. of the EARSel Workshop (Alpbach, Austria), Dec. 1982, ESA SP-193, Feb. 1983.
52. D. N. Held, “Amplitude calibration of spaceborne SAR’s in radar calibration,” Proc. of the EARSel Workshop (Alpbach, Austria), Dec. 1982, ESA SP-193, Feb. 1983.
53. J. C. Curlander, “Radiometric calibration of the SIR-C System,” in Progress in Imaging Sensors, Proc. ISPRS Symposium (Stuttgart), Sept. 1986, ESA SP-252, Nov. 1986.
54. R. C. Beal, A. D. Goldfinger, D. G. Tilley, and W. J. Geckle, “System calibration strategies for spaceborne SAR,” JHU/APL Rep. CP-084, Johns Hopkins University, Dec. 1981.
55. E. S. Kasischke and D. J. Gineris, “Further results of radiometric calibration of a multifrequency airborne SAR system,” in Proc. IGARSS ’89 Symposium (Vancouver, BC), July 1989.
56. P. Hoogeboom, “Preprocessing of side-looking airborne radar data,” Int. J. Remote Sensing, vol. 4, no. 3, pp. 631–637, 1983.
57. A. Freeman, “SIR-C calibration: An overview,” JPL Rep. #D-6997, Feb. 1990.
58. L. M. H. Ulander, R. K. Hawkins, C. E. Livingstone, and Lukowski, “Absolute calibration of the CCRS SAR,” IEEE Trans. Geosci. Remote Sensing, Vol. 29, pp. 99. 922–933, 1991.
59. A. Freeman, Y. Shen, J. J. Van Zyl, and J. D. Klein, “Calibration of NASA/JPL DC-8 SAR data,” Proc. IGARSS ’91 (Espoo, Finland), June 1991.
60. A. L. Bogush, Radar and the Atmosphere. Norwood, MA: Artech House, 1989.
61. A. Freeman, C. Werner, and Y. Shen, “Calibration of multipolarization imaging radar,” Proc. IGARSS ’88, pp. 335–339, 1988.
62. A. Freeman, Y. Shen, and C. L. Werner, “Polarimetric SAR calibration experiment using active radar calibrators,” IEEE Trans. Geosci. Remote Sensing, Vol. 28, Mar. 1990.
63. S. D. Robertson, “Targets for microwave radar navigation,” Bell Syst. Tech. J., vol. 26, pp. 852–869, 1947.
64. “Optical theory of the corner reflector,” Radiation Laboratory Rep. 433, Mar. 1944.
65. G. T. Ruck, D. E. Barrick, W. D. Stuart, and C. K. Krichbaum, Radar Cross-section Handbook, Vol. 2. New York: Plenum, 1970.
66. M. Keen, “Design criteria on for inclined planar radomes on radar corner reflectors used for spaceborne SAR calibration,” Electron. Lett., Vol. 21, No. 12, June 1985.
67. J. M. Lopez, O. Llopis, and M. A. Perennes, “Radar reflector for microwave remote sensing instruments external calibration,” in Proc. 4th International Colloquium on Spectral Signatures of Objects in Remote Sensing (Aussois, France), ESA SP-287, Apr. 1988.
68. W. C. anderson, “Polarization-dependent scattering properties of trihedral corner reflectors,” J. Electrical & Electronics Eng. (Australia), IE Aust. & IREE. Aust. vol. 5, no. 3, pp. 198–200, Sept. 1985.
69. D. R. Brunfeldt and F. T. Ulaby, “Active radar reflector for radar calibration,” IEEE Trans. Geosci. Remote Sensing, vol. GE-22, pp. 165–169, 1984.
70. P. Hartl and S. Bhagavathula, “An attempt to calibrate airborne SAR imagery using active radar calibrators and ground-based scatterometers,” Proc. IGARSS ’87, pp. 501–508, 1987.
71. K. Komiyuma, “Delayed-action reflector for external calibration of synthetic aperture radar,” Electron. Lett., Vol. 25, No. 7, pp. 468–470, Mar. 1989.
72. Ph. Hartl, F. Heel, W. Keydel, and H. Kietzmann, “Radar calibration techniques including propagation effects,” Adv. Space Research, Vol. 7, No. 11, pp. (11)259-(11)268, 1987.
73. M. C. Dobson, F. T. Ulaby, D. R. Bmnfeldt, and D. N. Held, “External calibration of SIR-B imagery with area-extended and point targets,” IEEE Trans. Geosci. Remote Sensing, Vol. GE-24, July 1986.
74. Y. Shen, J. D. Klein, and A. Freeman, “Tone generators in SAR applications,” Proc. IGARSS ’90 (Washington, DC), p. 1121, May 1990.
75. A. L. Gray, P. W. Vachon, C. E. Livingstone, and T. I. Lukowski, “Synthetic aperture radar calibration using reference reflectors,” IEEE Trans. Geosci. Remote Sensing, Vol. 31, pp 374–383, May 1990.
76. L. M. H. Ulander, “Accuracy of using point targets for SAR calibration,” IEEE Trans. Aerosp. Electron. Syst., vol. 27, pp. 139–148, Jan. 1991.
77. R. K. Moore and M. Hemmat, “Determination of the vertical pattern of the SIR-B Antenna,” Int. J. Remote Sensing, Vol. 9, No. 5, pp. 839–848, May 1988.
78. R. K. Moore, V. S. Frost, H. Westmoreland, D. Frank, and M. Hemmat, “Determining the vertical antenna pattern of a spaceborne SAR by observation of uniform targets,” Proc. IGARSS ’86 (Zurich, Switzerland), Vol. 1, pp. 469–472, 1986.
79. R. K. Hawkins, “Determination of antenna elevation pattern for airborne SAR using the rough target approach,” IEEE Trans. Geosci. Remote Sensing, vol. 28, pp. 896–905, Sept. 1990.
80. R. Bernard and D. Vidal-Madjar, “C-band radar cross-section of the Guyana Rain Forest: Possible use as a reference target for spaceborne radars,” Remote Sensing of the Environment, vol. 27, pp. 25–36, 1989.
81. F. T. Ulaby and M. C. Dobson, Handbook of Radar Scattering Statistics for Terrain. Norwood, MA: Artech House, 1989.
82. P. Blacksmith, R. E. Hiatt, and R. B. Mack, “Introduction to radar cross-section measurements,” Proc. IEEE, vol. 53, pp. 901–920, Aug. 1965.
83. R. B. Dybdal and R. H. Ott, “Coherent RF error statistics,” IEEE Trans. Microwave Theory and Tech., Vol. MTT-34, p. 1413, Dec. 1986.
84. C. C. Wackerman and E. S. Kasischke, “The effect of calibration errors on measuring the radar cross-section of diffuse targets with SAR,” in Proc. IGARSS ’89 (Vancouver, BC), pp. 261–263, July 1989.
85. R. E. Stovall, “Statistical technique for radar amplitude calibration,” IEEE Trans. Aerosp. Electron. Syst., vol. AES-15, pp. 815–823, Nov. 1979.
86. “Radar calibration,” in Proc. of the EARSeL Workshop (Alpbach, Austria), Dec. 1982, ESA SP-193, Feb. 1983.
87. R. B. Dybdal, “Radar cross section measurements,” Proc. IEEE, Vol. 75, No. 4, pp. 498–516, Apr. 1987.
88. E. S. Kasischke and G. W. Fowler, “A statistical approach for determining radiometric precision and accuracies in the calibration of synthetic aperture radar imagery,” IEEE Trans. Geosci. Remote Sensing, Vol. 27, July 1989.
89. D. N. Held et al., “The NASA/JPL multifrequency, multipolarization airborne SAR system,” Proc. IGARSS ’88 (Edinburgh, Scotland), pp. 345–349, 1988.
90. R. Sullivan et al., “Polarimetric X/L/C-band SAR,” Proc. IEEE National Radar Conf. (Ann Arbor, MI), pp. 9–14, 1988.
91. K. Carver et al., “Shuttle Imaging Radar-C Science Plan,” JPL Pub. #86-29, 1986.
92. P. C. Dubois and L. Norikane, “Data volume reduction for imaging radar polarimetry,” Proc. IGARSS ’87 (Ann Arbor, MI), pp. 691–696, 1987.
93. J. J. Van Zyl, C. H. Papas, and C. Elachi, “On the optimum polarizations of incoherently reflected waves,” IEEE Trans. Antennas Propagat., vol. AP-35, pp. 818–825, 1987.
94. H. A. Zebker, J. J. Van Zyl, and D. N. Held, “Imaging radar polarimetry from wave synthesis,” J. Geophys. Res., vol. 92, pp. 683–701, 1987.
95. J. J. Van Zyl, “Calibration of polarimetric radar images using only image parameters and trihedral corner reflector responses,” IEEE Trans. Geosci. Remote Sensing, vol. 28, pp. 337–348, May 1990.
96. K. Sarabandi, L. E. Pierce, and F. T. Ulaby, “Calibration of a polarimetric imaging SAR,” preprint, IEEE Trans. Geosci. Remote Sensing, vol. 30, May 1992.
97. P. S. Livingston and D. J. Kaplan, “Radar calibration procedure,” Tech. Note 1432, Naval Ocean Systems Center, San Diego, CA, Nov. 1985.
98. R. M. Barnes, “Antenna polarization calibration using in-scene reflectors,” Lincoln Laboratory Tech. Rep. TT-65, Sept. 1986.
99. M. A. Woods, “A calibration procedure for a coherent scattering matrix radar,” Royal Signals and Radar Establishment, Memorandum 3889, May 1986.
100. E. M. Kennaugh, “Polarization properties of corner reflectors with modified walls,” Ohio State University, Rep. 612–6, Jan. 1957.
101. E. M. Kennaugh and C. Chang, “Design and theoretical performance of reactive-wall corner reflectors,” Ohio State University Tech. Rep. NOW 64-0215-D, Jan. 1965.
102. H. A. Yueh, J. A. Kong, R. M. Barnes, and R. T. Shin, “Calibration of polarimetric radars using in-scene reflectors,” J. Electromagnetic Waves and Applications.
103. M. W. Whitt, F. T. Ulaby, P. Polatin, and V. V. Liepa, “A general polarimetric radar calibration technique,” IEEE Trans. Antennas Propagat., vol. 39, pp. 62–67, Jan. 1991.
104. A. Freeman, “A new system model for radar polarimeters,” IEEE Trans. Geosci. Remote Sensing, vol. 29, pp. 761–767, Sept. 1991.
105. M. Borgeaud, R. T. Shin, and J. A. Kong, “Theoretical models for polarimetric radar clutter,” J. Electromagnetic Waves and Applications, vol. 1, pp. 67–86, 1987.
106. J. D. Klein, “Calibration of complex quadpolarization SAR images using backscatter correlations,” submitted to IEEE Trans. Aerosp. Electron. Syst., 1989.
107. A. Freeman, J. J. Van Zyl, J. D. Klein, H. A. Zebker, and Y. Shen, “Calibration of Stokes and scattering matrix format polarimetric SAR data,” IEEE Trans. Geosci. Remote Sensing, Vol. 30, May 1992.
108. J. D. Klein and A. Freeman, “Quadpolarization SAR calibration using target reciprocity,” J. Electromagnetic Waves & Applications, vol. 5, no. 7, pp. 735–751, 1991.
109. K. Sarabandi, F. T. Ulaby, and M. A. Tassoudji, “Calibration of polarimetric radar systems with good polarization isolation,” IEEE Trans. Geosci. Remote Sensing, vol. 28, pp. 337–348, May 1990.
110. M. Whitt and F. T. Ulaby, “A polarimetric calibration technique with insensivity to target orientation,” Proc. IGARSS '90 (Washington, DC), pp. 1089–1092, May 1990.
111. K. Sarabandi and F. T. Ulaby, “A convenient technique for polarimetric calibration of single-antenna radar systems,” IEEE Trans. Geosci. Remote Sensing, vol. 28, pp. 1022–1033, Nov. 1990.
112. H. A. Zebker and Y. Lou, “Phase calibration of imaging radar polarimetric Stokes matrices,” IEEE Trans. Geosci. Remote Sensing, vol. 28, pp. 246–252, Mar. 1990.
113. D. R. Sheen, A. Freeman, and E. S. Kasischke, “Phase calibration of polarimetric radar images,” IEEE Trans. Geosci. Remote Sensing, vol. 27, pp. 719–731, Nov. 1989.
114. L. C. Graham, “Synthetic interferometer radar for topographic mapping,” Proc. IEEE, Vol. 62, No. 6, pp. 763–768, June 1974.
115. H. A. Zebker and R. M. Goldstein, “Topograpic mapping from interferometric SAR observations,” J. Geophys. Res., Vol. 91, no. B5, pp. 4993–4999, Apr. 1986.
116. H. Hirosawa and N. Kobayashi, “Terrain height measurement by synthetic aperture radar with an interferometer,” Int. J. Remote Sensing, vol. 7, pp. 339–348, 1986.
117. R. M. Goldstein, H. A. Zebker, and C. Werner, “Satellite radar interferometry: Two-dimensional phase unwrapping,” Radio Sci., vol. 23, pp. 713–720, 1988.
118. F-K. Li and R. M. Goldstein, “Studies of multibaseline spaceborne interferometric synthetic aperture radars,” IEEE Trans. Geosci. Remote Sensing, vol. 28, pp. 88–97, 1990.
119. R. K. Raney and P. W. Vachon, “A phase-preserving SAR processor,” Proc. IGARSS ’89 (Vancouver, BC), pp. 2588–2591, 1989.
120. R. Bamler, “A systematic comparison of SAR focussing algorithms,” Proc. IGARSS '91, Espoo, Finland, pp. 1005–1009, June 1991.
121. J. J. Anton, B. Friedlander, and J. P. Marsh, “An interferometric approach to SAR imagery of scenes with motion,” Proc. 13th ASILOMAR Conf. on Circuits, Systems and Computers, pp. 584–588, Nov. 1979.
122. M. Fujita et al., “SIR-B experiments in Japan: Sensor calibration and oil pollution detection over ocean,” IEEE Trans. Geosci. Remote Sensing, Vol. GE-24, July 1986.
123. M. Fujita, H. Naito, and N. Fugono, “SIR-B image calibration by a corner reflector array,” Int. J. Remote Sensing, Vol. 9, No. 5, pp. 849–856, May 1988.
124. D. G. Corr and A. M. Smith, “Experience gained from calibration of the SAR-580 system,” in Radar Calibration, Proc. of EARSel Radar Calibration Workshop, Alpsbach, Austria, Dec. 1982, ESA SP-193, Feb. 1983.
125. A. Freeman, “Calibration experiments with DC-8 SAR data,” in Proc. of theAIRSAR Workshop, JPL, Pasadena, CA, July 1990.
126. E. S. Kasischke, “Practical SAR radiometric calibration measurements and experiments,” Proc. IGARSS ’89 Symposium, Vancouver, B C, July 1989.
127. A. J. Sieber and W. Noack, “Results of an airborne SAR experiment over a SIR-B test Site in Germany,” ESA Journal, vol. 10, pp. 291–310, 1986.