Abstract:
This thesis presents a method for analysing the performance of a wireless in-building communication system operating in a three-dimensional environment. Performance analysis allows insight to be gained into the way systems should be designed and planned. Cochannel interference is shown to be a fundamental and limiting factor governing the performance of high capacity in-building systems and must be thoroughly understood for systems to operate reliably in the flexible and uncoordinated environment of a central business district. The approach used in this thesis to analyse the performance relies heavily on mathematical models. Outage probability is used to assess the impact of cochannel interference on the performance of a system. A technique is presented that allows the quality of reception over the entire service region to be considered. This is achieved by determining the cumulative distribution of outage probability over the floor which, as a measure, takes into account the likelihood of poor performance due to both the statistical properties of the channel and the spatial distribution of receiver locations. This approach differs from previous analytical treatments where typically only a single location in the service region is considered. The effect of multiple cochannel interferers distributed throughout the three-dimensional in building environment is also investigated in this thesis. Various base station deployment strategies and techniques to reduce cochannel interference are studied in this thesis. It is shown that simple base station deployment strategies, such as a single base station per floor, may not be able to comply with minimum interference requirements, even for large vertical reuse distances. As a result, techniques such as power control, diversity reception and distributed antennas are investigated to determine their effectiveness in reducing cochannel interference to acceptable levels. It is also shown that the expected reception qualities in a range of buildings is large indicating that the system performance and capacity are highly sensitive to the propagation parameters and geometric properties of the building.