The objective of this research proposal is to develop and evaluate the performance of novel communication techniques based on adaptive antenna and diversity methodologies for transmission of data and images over wireless channels. Adaptive techniques consist of relatively simple computational steps but are quite time consuming as they generally employ iterative procedures to extract the signal from interference. Diversity techniques, on the other hand, require statistical information and may involve complex computational steps especially for image communication but they are direct or non-iterative in nature. The goal of this research project is to study and comparatively evaluate the performance of these two methodologies for data and image transmission. Performance metrics to be employed will include computational time and accuracy of results. The first part of the proposal deals with adaptive antennas where the electromagnetic characterization of antennas is integrated with adaptive signal processing algorithms to enhance the performance of systems in the presence of near-field coupling and using unequally spaced receiving elements. The Performance of this methodology in blind adaptive equalization will also be considered. The second part of the proposal deals with the development of diversity reception schemes for data images. For data, the concept of predetection and post detection diversity combining schemes with memory that exploits channel memory will be investigated. channel memory will be investigated. For uncompressed as well as compressed images, diversity combining schemes based on image fusion concepts will be developed. Finite-state Markov channel models will be used for performance evaluation. Integration of these two methodologies with each other and with other methods that combat the effects of wireless channel impairments will also be explored. ***
