Title :
An L-band direct-sampling digital radiometer: design and performance evaluation
Author :
Fischman, Mark A. ; England, A.W.
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., Michigan Univ., Ann Arbor, MI, USA
Abstract :
This paper examines the noise characteristics of a direct RF sampling receiver whose architecture is suitable for high resolution aperture synthesis radiometry. The authrs have designed a 1.4 GHz direct-sampling digital radiometer (DSDR) to verify the discrete-time statistical model of the receiver and to evaluate current analog-to-digital converter technology. Several tests characterize the dynamic range and noise-equivalent sensitivity (NEΔT) caused by quantization, finite data sampling, and variations in signal bias. The results of a benchmark case study suggest that, with DSDR configured in a total power mode, a sensitivity of 0.2 K is attainable for Earth remote sensing applications like soil moisture retrieval
Keywords :
geophysical equipment; geophysical techniques; microwave detectors; radiometers; radiometry; remote sensing; terrain mapping; 1.4 GHz; DSDR; L-band; UHF; analog-to-digital converter technology; aperture synthesis radiometry; design; direct RF sampling receiver; direct-sampling digital radiometer; finite data sampling; geophysical measurement technique; land surface; microwave radiometry; noise characteristics; noise-equivalent sensitivity; performance; quantization; remote sensing; soil moisture; terrain mapping; Analog-digital conversion; Apertures; Dynamic range; L-band; Radio frequency; Radiometry; Sampling methods; Signal resolution; Signal synthesis; Testing;
Conference_Titel :
Geoscience and Remote Sensing Symposium, 1999. IGARSS '99 Proceedings. IEEE 1999 International
Conference_Location :
Hamburg
Print_ISBN :
0-7803-5207-6
DOI :
10.1109/IGARSS.1999.773458
