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Soundscape has been growing as a research field associated with acoustics, urban planning, environmental psychology and other disciplines since it was first introduced in the 1960s. To assess soundscapes, subjective validation is frequently integrated with soundscape reproduction. However, the existing soundscape standards do not give clear reproduction specifications to recreate a virtual sound environment. Selecting appropriate audio rendering methods, simulating sound propagation, and synthesising non-point sound sources remain major challenges for researchers. This thesis therefore attempts to give alternative or simplified strategies to reproduce a virtual sound environment by suggesting binaural or monaural audio renderings, reflection modelling during sound propagation, and less synthesis points of non-point sources. To solve these unclear issues, a systematic review of original studies first examines the ecological validity of immersive virtual reality in soundscape evaluation. Through recording and reproducing audio-visual stimuli of sound environments, participants give their subjective responses according to the structured questionnaires. Thus, different audio rendering, reflection modelling, and source synthesis methods are validated by subjective evaluation. The results of this thesis reveal that a rational setup of VR techniques and evaluation methods will be a solid foundation for soundscape evaluation with reliable ecological validity. For soundscape audio rendering, the binaural rendering still dominates the soundscape evaluation compared with the monaural. For sound propagation with consideration of different reflection conditions, fewer orders can be employed during sound reflection to assess different kinds of sounds in outdoor sound environments through VR experiences. The VR experience combining both HMDs and Ambisonics will significantly strengthen our immersion at low orders. For non-point source synthesis, especially line sources, when adequate synthesis points reach the threshold of the minimum audible angle, human ears cannot distinguish the location of the synthesised sound sources in the horizontal plane, thus increasing immersion significantly. These minimum specifications and simplifications refine the understanding of soundscape reproduction, and the findings will be beneficial for researchers and engineers in determining appropriate audio rendering, sound propagation modelling, and non-point source synthesis strategies.

Forward Scatter Radar (FSR) is a subclass of the bistatic radar, where the received target signal occurs mainly due to the direct path signal shadowing by the target body. Employing a separate deployed transmitter and receiver at considerable distance, the FSR can achieve a number of advantages, such as enhanced radar cross section, inherent detection ability of stealth target, reasonably low complexity design of system, more than the conventional monostatic radar. All of these features are attractive to the modern remote sensing systems. This thesis presents the research results of the detection and speed estimation of the ground target in FSR, which is a vital procedure for automatic targets classification. The hardware was designed and assembled by the Microwave Integrated Systems Laboratory (MISL), University of Birmingham. The experimental data used in this thesis have been collected from real field environments at multiple locations and from various targets. The complex automatic target detection and speed estimation algorithm were integrated to achieve higher accuracy. The main problem investigated in this research and the appropriate results are dedicated to automatic target speed estimation in complex FSR operational scenario. The improved and originally proposed algorithms are discussed and shown throughout the chapters in great detail. The measurements are implemented in large load of work and the database is created for the validation of these algorithms.