Information content of the kernel matrix for the phase function retrieval problem

We investigate the information content of the radiation measurements to be used in the retrieval of the scattering properties of the atmosphere with t he perturbation technique that we previously introduced. Applying this tech nique to different sets of data, we obtained solutions with varying accurac y. An analysis of these solutions shows that selecting linearly independent data in directions corresponding to small values of the scattering angle i ncreases the number of pieces of information. (This result is in accord wit h conclusions reached by other researchers, based on a variety of criteria. ) This information content should be largely independent of the method or m ethods employed to perform the inversion procedure. (C) 1999 Optical Societ y of America.