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Comparison of dielectric models and evaluation of the penetration depth of L-band S-band (NISAR mission) microwave SAR signals into the ground

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Abstract

Here we study the effect of soil texture, incidence angle and soil moisture content on the penetration depth of microwave pulses into the ground. In doing so, we have compared the penetration depth of SAR signals in soil using the Dobson empirical, Dobson semi-empirical and Hallikainen empirical model over samples collected at three different locations in Bhopal, Madhya Pradesh, India. We observed all these models results in different penetration depth for the same set of soil parameters at the same frequency. Further, we explored the potential of the proposed L- and S-band sensor of the upcoming NISAR mission for the estimation penetration depth in soil at different incident angles. According to the NISAR mission science user handbook, the frequency used for L- and S-band SAR systems are 1.25 GHz and 3.22 GHz respectively with variation in the incident angle of 33 degrees to 47 degrees respectively.
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