One of the most crucial technologies in the 5G to come is the use of massive MIMO. However, all the articles I read recently suggest that MIMO is merely the good old antenna/space diversity techniques. Am I missing something?
Massive MIMO is a variation, where you use a number of base station antennas tending to infinity, and a single UE antenna. This allows focusing beams to points in space, making even better use of spectrum. Now multiple UEs can be served simultaneously in that RF channel.
Well a lot of attention is paid on (reciprocal) channel estimation, you want to estimate the channel between the user and the N Massive MIMO antennas quickly and ideally using fewer symbols as the number of antennas and their correlation increases
We have a new project on channel estimation for heteregenous networks when the macrocells and small cells use the same carrier frequency and also different carrier frequencies. It seems to be very exciting.
To combat fading effect, an array of antennas is used. Diversity techniques have been recognized as an effective means which enhances the immunity of the communication system to the multipath fading. Multiple-Input Multiple-Output (MIMO) is an antenna technology – Sometimes called smart antenna technology. MIMO antenna array is used in antenna diversity system.