Computational Techniques for the Analysis and Design of Digital Communication Systems

摘要

In this report we introduce some computational techniques for the analysis and design of digital communication systems, possibly operating over a nonlinear channel (a typical example is a digital satellite system, with the transponder amplifier working at or near saturation for better efficiency). We first consider evaluation of error probabilities when the disturbances are only incompletely known. Then we describe a combined simulation-and-analytical technique to evaluate the power density spectrum of a digital signal passed through a nonlinear channel. Next, we consider the problem of designing and evaluating the performance of the optimum linear receiving filter for transmission over a nonlinear channel. Finally, we consider Ungerboeck codes; a new class of multidimensional codes is introduced, its applications discussed, and an important property concerning their power spectral densities is shown. Keywords: Digital communication systems; Nonlinear channels; Channels with memory; Error probability-Ungerboeck codes; Computation of power spectra; and Optimum receiver filter.