The propagation channel is a vital but invisible part of any wireless communications system. As wavelengths get shorter, multipath effects become more pronounced, causing small scale fading in narrowband channels, and inter-symbol interference in wideband systems because of delay spread in the channel impulse response. Multipath propagation becomes more pronounced as the wavelength decreases, and at the frequencies around 2GHz assigned for 3rd. generation cellular 'phones and personal communication services, multipath is pervasive, and very dependent on the built environment and topography. Multipath makes non-line-ofsight (NLOS) operation possible, but also introduces a degree of randomness and unpredictability which complicates radio system design. System designers, and researchers pursuing improved methods of communicating information need realistic channel statistics and models to progress. At the start of this thesis project, no wideband outdoor propagation data had ever been published for the Australian environment The primary objective of the project was to develop and build wideband channel-sounding instrumentation operating at 1.89GHz, and to investigate propagation conditions in a variety of cities and locations, to allow the comparison of multipath behaviour in the Australian environment with results from overseas countries.