Brightness Temperatures From Layered Lossy Medium With Rough Surfaces by Combining FDTD and Coherent Methods

The brightness temperatures from layered lossy medium with rough surfaces, where the physical temperature varies with depth, are computed by using the coherent method, with the field distribution computed by using the finite difference time domain method. The major contribution of the proposed method lies in its flexibility to compute the brightness temperatures from a layered medium with rough interfaces and spatially varying physical temperature. The brightness temperatures from a half-space lossy medium are validated by comparing with data in the literature, and the maximum error of the simulation results, as compared with the literature, is 4.7 K (1.6%), which is slightly above the threshold of 1%.