On the Capacity of the DiscreteTime Channel with Uniform Output Quantization
Abstract
This paper provides new insight into the classical problem of determining both the capacity of the discretetime channel with uniform output quantization and the capacity achieving input distribution. It builds on earlier work by Gallager and Witsenhausen to provide a detailed analysis of two particular quantization schemes. The first is saturation quantization where overflows are mapped to the nearest quantization bin, and the second is wrapping quantization where overflows are mapped to the nearest quantization bin after reduction by some modulus. Both the capacity of wrapping quantization and the capacity achieving input distribution are determined. When the additive noise is gaussian and relatively small, the capacity of saturation quantization is shown to be bounded below by that of wrapping quantization. In the limit of arbitrarily many uniform quantization levels, it is shown that the difference between the upper and lower bounds on capacity given by Ihara is only 0.26 bits.
 Publication:

arXiv eprints
 Pub Date:
 January 2009
 DOI:
 10.48550/arXiv.0901.2545
 arXiv:
 arXiv:0901.2545
 Bibcode:
 2009arXiv0901.2545W
 Keywords:

 Computer Science  Information Theory
 EPrint:
 submitted to ISIT 2009