Intelligent service convergence Convergence of wireless communications networks with digital broadcasting systems is a vision for mobile services beyond the third generation (3G) investigated within the FLOWS project. Digital Economy © Shutterstock The worldwide convergence of broadcasting, telecommunications and Internet has created many opportunities to provide new services to consumers by combining existing networks into a seamless entity. The research efforts of the FLOWS project to converge multiple wireless standards added up to an emerging vision for enhanced mobile services. The main concept adopted by the FLOWS project was a common access network based on the Internet Protocol (IP). Onto this common network, a user with a single mobile terminal would be connected through access points based on the most suitable of available wireless standards, depending on the user's location and mobility. This will not only provide access to enhanced voice services, but will also augment them with entertainment and information services. As a means to achieve flexible convergence of multiple wireless standards, the FLOWS project partners designed and demonstrated Multiple input-multiple output (MIMO) antenna arrays to be used in the wireless terminals. The number of antenna elements in a single terminal may range from two in a small handset, to four in a Personal digital assistant (PDA), and up to sixteen or even more in a laptop. However, spacing between antenna elements is conditioned by their mutual coupling, which ideally should be as low as possible to ensure the effectiveness of the MIMO antenna system. Researchers at the University of York investigated issues related to the multi-element antenna configuration that affects the performance of MIMO signal processing system. In addition to the directional response of the antenna elements, the effect of mutual antenna coupling on the information capacity of a MIMO channel was simulated with the use of a finite scatterers model. It was well known that mutual antenna coupling can be compensated for while the MIMO signal is being processed. Nonetheless, the FLOWS project partners elucidated any controversy that persisted regarding the possibility of mutual antenna coupling having a positive effect on the MIMO channel capacity. This was an essential step before new antenna configurations could be proposed for integration into multi-mode user terminals.
