There is at present a worldwide effort to develop next-generation wireless communication systems. It is envisioned that many of the future wireless systems will incorporate considerable signal processing intelligence in order to provide advanced services such as multimedia transmission. In general, wireless channels can be very hostile media through which to communicate, due to substantial physical impediments, primarily radio-frequency interference and the time-varying nature of the channel. The need to provide universal wireless access at high data rates (which is the aim of many emerging wireless applications) presents a major technical challenge, and meeting this challenge necessitates the development of advanced signal processing techniques for multiple-access communications in non-stationary interference-rich environments.
This research involves the development of adaptive signal processing algorithms and architectures for application in future wireless communications systems featuring high user mobility, high data rate and high quality of service. The primary emphases of this research are on advanced receiver signal processing techniques, and on advanced transmitter signal processing techniques for wireless systems. The first of these focuses on developing adaptive signal reception techniques for jointly combating various impairments in time-varying wireless channels, such as radio-frequency interference (narrowband interference, multiple-access interference, impulsive ambient noise), multipath fading, channel dispersion, etc. A particular approach that will be examined in depth is the exploitation of the redundancy introduced by channel coding at the receiver for interference mitigation and channel tracking. The second addresses adaptive signal transmission techniques in time-varying wireless channels for improving network capacity. Specifically, adaptive antenna array transmission techniques and adaptive frequency hopping techniques are being studied, with the focus on rapid adaptivity to dynamic channel environments. This research is expected to culminate in the formulation of novel signal processing techniques and system design concepts applicable to future wireless communication systems. It is also anticipated that this research will influence many current and next generation communication systems planners and designers, to bring the promise of many new research techniques into the arena of wireless communications.
