TABLE OF CONTENTS Characteristics of future mobile/wireless radio networks will be quite different to those of current networks. Compared to a uniform spatial distribution of, say, voice traffic in a GSM cell, a much more nonuniform traffic will be witnessed in future networks in terms of spatial distribution within the cell of voice and data, in particular with even higher demands for a much broader bandwidth stretching from low to high bit rates for higher mobility. At the same time, the more we move to higher frequencies, the more the range of the cell shrinks compared to current systems (e.g., GSM cells). This means that in order to cover the same geographical area, more BSs need to be deployed, which leads to much higher deployment costs for operators. Apart from those new needs, future network deployments will need to solve more adequately the problems that exist in current conventional network deployments and that are related to the issue of coverage; either extend/stretch the coverage of cells or provide better coverage in shadowed areas within a cell in terms of, say, better QoS. The above needs/requirements will need to be addressed either by new technologies (for instance, new air interface with conventional cellular architectures) or by novel concepts that will introduce new network elements and architectures.
One of those concepts that can address capacity and coverage issues is that of relaying. Relaying has attracted a lot of interest in recent years mainly through research...
