Speaker:
Title:
The capacity of the binary-input random code division multiple-access channel
Abstract:
Communication through a mutiple-access gaussian channel using a random code division scheme will be discussed. When the input signal is gaussian the capacity can be calculated from the spectral distribution of random matrices related to the code division scheme. However for binary or other discrete input signals it is not known how to use random matrix methods. It will be explained how it is possible to apply interpolation methods, developed in recent years in the context of spin-glasses, to provide a tight bound on the capacity. The bound matches a formula obtained by Tanaka thanks to the replica trick.