Key Technologies Of Massive MIMO Beyond B4G

In the past ten years, there has been an explosive growth of mobile Internet. The demand for data traffic communication becomes very large. However, the conventional MIMO technology has reached its bottleneck, and cannot handle the problem right now. At this time, the massive mimo technology showed up, it works in TDD mode, and can serve a lot of terminals with a lot of antennas deployed in the base station.First, we analyzed the spectral efficiency of uplink massive mimo system, both in idea and non-ideal channel condition. We also analyzed the effect of pilot contamination on massive mimo system. Simulation shows that the pilot contamination will eventually limit the performance of massive mimo system.We then discussed the power scaling problem. We found out that while keeping the same data rate, we can scale down the power of terminals by increasing the base station antenna number. Under the assumption of pilot contamination, we proposed a joint algorithm, which can jointly optimize the data power and pilot power under per-user SINR and power constraint. Simulation results show that the joint optimization algorithm can highly reduce the transmitting power of users, thus improving the energy efficiency of the massive mimo system, it also shows that the transmission power can be cut off by lOdB compared to equal power allocation.