Future Radio Systems

Overview

The research activities in this area encompass both network and transceiver link level issues. A key factor in the design and performance of any wireless communication system is the transmission medium. Link losses will determine operating range whilst multipath dispersion can give rise to fading and intersymbol interference, requiring anti-multipath techniques such as equalisation and diversity. In a cellular communication system, the BS-MS link is not only affected by its own RF channel but also from co-channel and adjacent channel signals (and their associated RF channels). Further, in CDMA systems, power control is a key issue in optimising capacity.

Thus, in order to optimise capacity (with due regard to deployment costs), knowledge of the propagation medium is required. A parametric analysis of network capacity as a function of planning uncertainties (i.e. incorrect assumptions regarding channel behaviour) for second generation systems was been undertaken as part of a PhD thesis (supported by BT Labs under the VURI on Mobility). In parallel with this activity, a number of channel measurement systems have been developed to support fundamental electromagnetic propagation research at the University of Birmingham with the group headed by Dr. Costas Constantinou. Field measurements taken by the Oxford/VURI team have also been used by VURI members at the University of Bristol in assessing UMTS microcellular performance.