A Look Beyond Massive MIMO – Working with a Huge Number of Antennas
A Look Beyond Massive MIMO – Working with a Huge Number of Antennas Future wireless systems are expected to provide huge growth in user bit rates and overall required bit rates, and the same might be expect for beyond 5G systems. This means a substantial spectral efficiency increase, which must be achieved while maintaining or even improving the power efficiency. To accomplish this one needs to employ new transmission techniques, with the most promising ones based on the use of a large number of antennas. For this reason, massive MIMO (Multiple-Input and Multiple-Output) schemes, involving tens or even hundreds of antennas, are a key component of 5G, since they allow high capacity gains, while enabling significant power savings. Clearly, the evolution beyond 5G will involve even more antennas. A new and revolutionary technique able to improve substantially the performance of wireless communication networks is to smartly changing the propagation characteristics of the wireless channel through the use of RIS (Reconfigurable Intelligent Surfaces), which are made of a large number of low cost passive reflecting elements able to independently change the amplitude and/or phase of the incident signal so as to achieve specific propagation effects. LIS (Large Intelligent Surfaces) are the natural evolution of massive MIMO schemes. They will employ many thousands of antenna elements, allowing huge capacity gains, as well accurate positioning and efficient energy harvesting techniques. However, the implementation of these techniques involves considerable challenges. In this talk we give an overview of potentialities and challenges of systems with a huge number of antennas. We start by making an overview on the evolution from MIMO to massive MIMO, and its extension to RIS and LIS and cell free systems. Then we present the main features of those systems, as well as the implementation constraints and challenges, as well as potential solutions. Room: 1300, 12920 SE 38th St, Bellevue, Washington, United States, 98006