Multiple antennas, multiple gains
Massive antenna systems can greatly increase spectrum efficiency. Combining data streams arriving from different paths and at different times, smart antenna technology optimises data speed and provides gains in link capacity and spectral efficiency. Research conducted within the AMIMOS (Agile MIMO systems for communications, biomedicine, and defence) project enabled significant advances in state-of-the-art knowledge on the use of MIMO technology in wireless communications, radar systems, and biomedical imaging and therapeutic ultrasound. Scientists came up with new ways for base stations to successfully coordinate their transmissions in the downlink and jointly process the received signals in the uplink. This improved coverage and data rates for mobile users without the need for utilising additional energy. New coding schemes capable of leveraging access to radio relays and MIMO technologies enabled wireless cellular systems and data networks to become more reliable and secure. In collaboration with US-based scientists, AMIMOS members developed waveform design methods to construct radar signals that can improve the resolution and accuracy of MIMO radar systems. These techniques can also find application in underwater communications systems. A prototype was developed to test use of MIMO in these two areas. Application of acoustic MIMO signal processing in biomedicine led to a novel ultrasound-based adaptive approach for blood velocity estimation. Results have the potential to improve medical diagnosis of heart valve problems through quick and non-intrusive examinations. Further, in collaboration with a US team, scientists devised an advanced method that enhances image quality in magnetic resonance imaging. Project dissemination activities included 346 publications in journals, presentations and conferences. Two books called 'Waveform Design for Active Sensing Systems – A Computational Approach' and 'Optimal Resource Allocation in Coordinated Multi-Cell Systems' co-authored by AMIMOS members helped spread the word about project results.
Keywords
MIMO, spectrum efficiency, wireless communications, radar systems, biomedical imaging
