Fully polarimetric radiometer system for airborne remote sensing
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Doctoral thesis (article-based)
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Report / Helsinki University of Technology, Laboratory of Space Technology, 53
AbstractAs a result of the increasing interest in polarimetric microwave radiometer measurements, a fully polarimetric radiometer system was developed and thoroughly tested in this work. The system is primarily designed for airborne remote sensing; however, ground-based and laboratory measurements are possible as well. The feasibility of the system for remote sensing was demonstrated in laboratory measurements and in an airborne experiment. The system comprises a polarimetric radiometer at 36.5 GHz (the Fully Polarimetric Radiometer) and a passive calibration standard (the Fully Polarimetric Calibration Standard). This work is the first successful demonstration of a polarimetric remote sensing radiometer that is based on analog direct cross-correlating architecture; analog multipliers were used as correlating elements. Compared to other possible polarimetric radiometer topologies, the applied solution possesses several advantages, e.g., the simple structure of both the receiver and the correlator, which is beneficial in terms of reliability, costs, mass, size, and power consumption. A novel fully polarimetric end-to-end calibration technique was developed. The theoretical background of the technique is thoroughly studied, the mathematics necessary to determine the a priori Stokes vectors and error analysis are derived, and a calibration matrix inversion technique is presented. Using the principles presented, fully polarimetric calibration standards were developed at 10.6 GHz and 36.5 GHz and their function demonstrated. The uncertainties associated with the practical implementation of fully polarimetric calibration standards for wind vector remote sensing are discussed. Using the developed radiometer system, an airborne experiment was conducted over the Gulf of Finland. Polarimetric dataset obtained for a semi-enclosed sea composed of brackish water is presented. The results suggest that the relationship between the wind vector and the Stokes parameters may vary locally.
calibration, correlators, polarimetry, radiometers, remote sensing, wind, wire grids
- Additional errata file available.
- Lahtinen J., Gasiewski A. J., Klein M. and Corbella I., 2003. A calibration method for fully polarimetric microwave radiometers. IEEE Transactions on Geoscience and Remote Sensing 41, No. 3, pages 588-602. [article1.pdf] © 2003 IEEE. By permission.
- Lahtinen J. and Hallikainen M., 1999. Fabrication and characterization of large free-standing polarizer grids for millimeter waves. International Journal of Infrared and Millimeter Waves 20, No. 1, pages 3-20.
- Lahtinen J. and Hallikainen M., 2003. HUT Fully Polarimetric Calibration Standard for microwave radiometry. IEEE Transactions on Geoscience and Remote Sensing 41, No. 3, pages 603-611. [article3.pdf] © 2003 IEEE. By permission.
- Koistinen O., Lahtinen J. and Hallikainen M., 2002. Comparison of analog continuum correlators for remote sensing and radio astronomy. IEEE Transactions on Instrumentation and Measurement 51, No. 2, pages 227-234. [article4.pdf] © 2002 IEEE. By permission.
- Lahtinen J., Pihlflyckt J., Mononen I., Tauriainen S., Kemppinen M. and Hallikainen M., 2003. Fully polarimetric microwave radiometer for remote sensing. IEEE Transactions on Geoscience and Remote Sensing 41, No. 8, pages 1869-1878. [article5.pdf] © 2003 IEEE. By permission.