Estimation of penetration depth in a random medium using frequency decorrelation of the backscattered field

Frequency decorrelation of co-polarized and cross-polarized fields backscattered from a random medium is shown to be sensitive to the penetration depth and the physical parameters of the medium. The backscatter decorrelation bandwidth is shown to be inversely proportional to the penetration depth. Measurements conducted on snow under wet and dry conditions using 35 and 94 GHz scatterometers showed the sensitivity of the backscatter decorrelation bandwidth to snow wetness, particularly at 94 GHz. The backscatter decorrelation bandwidth can be used to estimate the penetration depth and water content in snow and soil media