The effect of user distribution on a linear Cellular Multiple-Access Channel

Abstract

The Gaussian cellular multiple-access channel (GCMAC) has been the starting point for studying the Shannon-theoretic limits of cellular systems. In 1994, a simple infinite GCMAC was initially introduced by Wyner and was subsequently extended by researchers to incorporate flat fading environments and power-law path loss models. However, Wyner-like models, preserve a fundamental assumption, namely the symmetry of User Terminals (UTs). In this paper, we investigate the effect of this assumption on the sum-rate capacity limits, by examining the case of distributed and thus asymmetric UTs. The model under investigation is a GCMAC over a linear cellular array in the presence of power-law path loss and flat fading. In this context, we study the effect of UT distribution for cell-centre and cell-edge UTs and we show that its effect is considerable only in the case of low cell density.