Generalised information theory for inverse problems in signal processing

A powerful technique for the solution of a number of experimental in verse problems, described by an underlying first-kind Fredholm equation is presented. Such problems include, for example, diffraction-limited imaging and the analysis of laser light scattering data. The technique requires the construction of the `singular system¿¿ of the propblem which then provides exact orthonormal bases both for the description of sampled and truncated measured data and for the reconstructed continuous object `solution¿¿ of the inversion. The singular-system approach may ber regarded as a theory of information which generalises in several directions the well known classical concepts of Shannon and Nyquist.