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In this paper we study the effect of Base Station (BS) and User Terminal (UT) shadowing correlation on the capacity of the Gaussian Cellular Multiple Access Channel. We also build a Monte Carlo simulator using realistic system parameters and distance dependent shadowing correlation estimation models. We are able to properly verify the theoretical analysis and we provide an insight on the maximum achievable capacity for real cellular systems.

Capacity can be increased by exploiting the space dimension inherent to any wireless communication system. Recent information theoretic results show that simultaneous use of multiple receive and multiple transmit antennas can offer dramatic increase in capacity. In this paper each cell-site receiver and each user terminal is assumed to be equipped with multiple antennas. Then,under a per transmit antenna power constraint, a closed form expression for the optimum capacity is found using the well known Wyner's model. The results show that even one antenna per-user is enough to achieve the limit and offer an insight in the behavior of the capacity for a Gaussian cellular Multiple-access Channel (GCMAC) with MIMO in different fading environments.

Abstract-With the emergence and continuous growth of wireless data services, the value of a wireless network is not only defined by how many users it can support, but also by its ability to deliver higher data rates. Information theoretic capacity of cellular systems with fading is usually estimated using models originally inspired by Wyner's Gaussian Cellular Multiple Access Channel (GCMAC). In this paper we extend this model to study the cellular system with users distributed over the cellular coverage area. Based on the distance from the cellsite receiver, users are grouped as tiers, and received signals from each tier are scaled using a distance dependent attenuation factor. The optimum capacity in fading environment is then found by calculating the path-loss for users in each tier using a specific path-loss law and some interesting insights are derived. The results correspond to a more realistic model which boils down to Wyner's model with fading, with appropriate substitutions of parameter values. The results are verified using Wyner's model with fading and Monte-Carlo simulations. Insights are provided for the real world scenarios.

Abstract-We derive an analytical formula for the sum rate of the uplink of a linear network of cells when clustered joint processing is adopted among the base stations in a generalised fading environment. An inter-cluster interference allowance scheme is considered and various user power allocation profiles are investigated in terms of optimal achievable sum rate to highlight that cell-based power allocation is preferable to cluster-based. The contribution of each base station on the cluster sum rate is investigated and its importance is discussed. Numerical results are produced for a real-world scenario showing how medium density systems are the most viable case for clustered system design by achieving > 80% of the global cooperation capacity.