"This proposal targets the emerging frontier research field of multiple-input multiple-output (MIMO) systems along with several innovative and somewhat unconventional applications of such systems. The use of arrays of transmitters and receivers will have a profound impact on future medical imaging/therapy systems, radar systems, and radio communication networks. Multiple transmitters provide a tremendous versatility and allow waveforms to be adapted temporally and spatially to environmental conditions. This is useful for individually tailored illumination of human tissue in biomedical imaging or ultrasound therapy. In radar systems, multiple transmit beams can be formed simultaneously via separate waveform designs allowing accurate target classification. In a wireless communication system, multiple communication signals can be directed to one or more users at the same time on the same frequency carrier. In addition, multiple receivers can be used in the above applications to provide increased detection performance, interference rejection, and improved estimation accuracy. The joint modelling, analysis, and design of these multidimensional transmit and receive schemes form the core of this research proposal. Ultimately, our research aims at developing the fundamental tools that will allow the design of wireless communication systems with an order-of-magnitude higher capacity at a lower cost than today; of ultrasound therapy systems maximizing delivered power while reducing treatment duration and unwanted illumination; and of distributed aperture multi-beam radars allowing more effective target location, identification, and classification. Europe has several successful industries that are active in biomedical imaging/therapy, radar systems, and wireless communications. The future success of these sectors critically depends on the ability to innovate and integrate new technology."