AbstractMillimeter radiowave systems offer an excellent means of creating a user and environment friendly scalable system that can be tailored economically as well as technically to small and large communities and provide a number of different services. In fact, the convergence of broadcast, communication and data services will have a near perfect platform in millimeter wave radio. The millimeter wave band is suited for broadband services because of the large available bandwidth, high frequency reuse and the reduced size of radiating and receiving antennas and electronic components.
For the development of a wireless system operating at millimeter wave frequencies, in depth knowledge of the radio wave propagation aspects is essential. For broadband services systems it compromises the analysis of both path loss for the estimation of cell coverage and impulse response for the evaluation of the wideband radio channel characteristics. A considerable amount of work has been documented in these two areas in the past concerned with modelling and measurements in indoor and outdoor scenarios. However, there is a lack of theoretical statistical models and experimental data dealing with the operation of such links.
This thesis presents a novel analytical statistical model, which assumes that the received signal is the superposition of the direct field and a finite sum of scattered fields. The scattering fields can be obtained using the tangent-plane (Kirchhoff) approximation over an infinite surface and plane wave incidence. This method assumes that at each point of the scattering surfaces, the wave field may be represented in the form of the sum of the incident field, which is the field of the assigned sources in infinite, empty space, and the field reflected according to the laws of geometrical optics from the plane which is tangential to the scattering surface at each point. Simulation of the radio channel based on this model assume that the variability in signal level arising from random choice of scattering centers is statistically similar to the signal variability experienced due to receiver displacement in measurements. The performance of the model has been evaluated in an extensive experimental programme, which was part of this research. Preliminary results of this project have been published in the IEE Proceedings on Microwaves, Antennas & Propagation.
|Date of Award||Feb 2007|
|Supervisor||Jurgen Richter (Supervisor)|