MICROWAVE IMAGING OF THE BRIGHTNESS TEMPERATURE DISTRIBUTION OF EXTENDED AREAS IN THE NEAR AND FAR-FIELD USING 2-DIMENSIONAL APERTURE SYNTHESIS WITH HIGH-SPATIAL-RESOLUTION
M. Peichl et al., MICROWAVE IMAGING OF THE BRIGHTNESS TEMPERATURE DISTRIBUTION OF EXTENDED AREAS IN THE NEAR AND FAR-FIELD USING 2-DIMENSIONAL APERTURE SYNTHESIS WITH HIGH-SPATIAL-RESOLUTION, Radio science, 33(3), 1998, pp. 781-801
Aperture synthesis is an attractive alternative to conventional passiv
e microwave imaging systems for remote sensing applications. Whenever
a high spatial resolution is desired or the imaging process should wor
k like an optical camera or when microwave remote sensing in the near
field has to be distance adaptive, conventional systems cause a lot of
problems. However, aperture synthesis for practical applications requ
ires a lot of single receivers and correlators. This can cause other p
roblems because of the large number of possible imperfections. To get
an estimation of such effects, the imaging expressions for the apertur
e synthesis principle are developed for the near-and far-field conditi
ons of a real system. To support the theory and to get an estimation o
f the feasibility of this imaging method, a simple experimental system
is described and experimental results of high spatial resolution for
the near and far field are shown. For the near-field case a special re
construction algorithm was developed and is described theoretically an
d validated by the experiments. A discussion of the temperature resolu
tion of aperture synthesis concludes the paper.