Impact of angular spread on massive MIMO channel estimation

Large scale antenna arrays technology has the potential of bringing many advantages to future wireless systems. Energy and spectral efficiency are going to be the most important features. Hence, accurate estimate of channel state information (CSI) makes these advantages achievable. This paper investigates the effects of angular spread on the accuracy of channel estimation for massive multiple input multiple output (MIMO) wireless communication systems. The model we consider consists of user equipment (UE) and a base station with large antenna array. Linear minimum mean square error (LMMSE) is used to estimate the uplink channel of a massive MIMO system using a pilot signal. It is shown that higher spatial correlation (SC) positively affects the accuracy of channel estimation when the signal to noise ratio is kept constant.