Performance analysis of DOA Estimation Algorithm in massive MIMO Network

Abstract

This generation has seen a massive growth in the number of connected wireless devices. Billions of devices are connected and managed by wireless networks at the same time; each device needs a high throughput to support applications such as voice, real-time video, movies, and games. As solution, Massive multiple-input multiple-output (MIMO) technology has been proposed, which is a multiple access technology where a base station (BS) serves many users in the same time-frequency resource according to his very large number of antennas (distributed). Thanks to its advantages, Massive-MIMO promises as a candidate technology for next generations of wireless systems. One of the research challenges often encountered (in the context of massive MIMO) is the problem of two-dimensional (2D) estimation (in azimuth and elevation) of the direction-ofarrival (DOA) at the BS. When 2D-DOA estimation is well done, it improves the performance of the beam-forming mechanism that helps the network to have higher signal to noise ratio (SNR) and the prevention inter-user interference (pilot contamination) which naturally leads to an increase in the total capacity and higher network efficiency of the system. In the context of the two-dimensional estimation of the DOA, several recent research have opted different algorithms for estimation of 2D-DOA by using different antenna structures and their respective performances are compared in terms of the complexity/precision. Research conducted on this topic (2D-DOA estimation algorithms) considered a time-invariant channel that is different from the reality of Massive-MIMO systems applied in mobile communication whose channel is time-variant (Multi-path channel). Here comes the idea of my research that study comparatively the Performance of 2D-DOA estimation algorithms by considering the time-variant channel (multi-path channel) in order to recommend a suitable DOA estimation algorithm for 5G systems. In this work, we analyze the 2D-DOA estimation algorithms that uses L-shaped antenna array structure DOA by evaluating the mean-squared error in azimuth and elevation. By analyzing the 2D-DOA estimation algorithms that uses L-shaped antenna array; we observe that PM perform better than others because of presenting lower value of RMSE, SNR and AS in different cases of simulation.