Final Report Summary - AMIMOS (Agile MIMO Systems for Communications, Biomedicine, and Defense) The Agile MIMO Systems for Communications, Biomedicine and Defense (AMIMOS) project targets the important research field of multiple-input multiple-output (MIMO) system technology: the technique of using sensor arrays of transmitters and/or receivers in radio communications, as well as in electromagnetic and acoustic sensing systems. The use of multiple sensors, coupled by advanced signal processing, have been identified as a key strategy to increase the data-rate and coverage of future wireless communication systems, increase the resolution and accuracy of radar systems, and simultaneously improve the efficiency and reduce harmful side-effects in ultrasound imaging and therapy systems. By developing the underlying principles and theories behind MIMO, the AMIMOS project has been able to significantly advance the state-of-the-art and knowledge in each of these areas. The research conducted within the project has resulted in 91 research papers in scientific journals, and 75 research papers presented at international conferences, has had a significant impact on how researchers world-wide think about MIMO, and has provided a set of new technologies ready for implementation. A number of PhD students have also graduated within the project, and have continued the development and standardization of MIMO technologies, for example for fifth generation (5G) cellular networks, in industry and academia.In the context of wireless communication systems, and cellular systems in particular, we have found new ways for base stations to successfully cooperate and coordinate their transmission, in a distributed manner with manageable signaling overhead, to provide improved coverage and data-rates to mobile users, while requiring less energy to do so. By developing new codes, particularly suited for networked scenarios and capable of leveraging access to radio relays and MIMO technologies, we have provided ways to make such wireless cellular systems and data networks more reliable and secure. We have designed and built a hardware MIMO testbed, where novel ideas can quickly be tested and evaluated. At the same time we have continued to develop the theoretical underpinnings of these technologies, thus giving insights into the fundamental limits of wireless communication systems and provided novel ideas on how to further improve the systems that exist today.In collaboration with researchers at the University of Florida, we have developed waveform design methods to construct radar signals capable of improving the resolution and accuracy of MIMO radar systems. It turns out that the very same design methodologies are also applicable in underwater communications systems and a prototype system has already been built to test these ideas. These developments will prove useful in both applications relevant to the defense industry as well as in the private sector.The application of acoustic MIMO technologies in biomedicine has led to a novel ultrasound-based adaptive approach for blood velocity estimation. These results have the potential to improve medical diagnoses of, for example, heart valve problems during quick and non-intrusive examinations. Further, in collaboration with researchers at Stanford University, we have devised methods to further improve the image quality in medical resonance imaging (MRI): a method used in medical treatments and science to visualize the detailed internal structures of, for example, humans.Finally, we have actively disseminated our research findings more broadly through the publication of articles in scientific magazines, and by active participation at scientific conferences across the world. Two books: “Waveform Design for Active Sensing Systems – A Computational Approach”, co-authored by AMIMOS co-applicant P. Stoica, and “Optimal Resource Allocation in Coordinated Multi-Cell Systems”, co-authored by former AMIMOS PhD student E. Björnson, have helped spread the knowledge gained within the project.
