Mean angle of arrival and Angular Spread estimation: Maximum Likelihood vs two low-complexity approaches

In this paper, three different nominal Angle of Arrival (AoA) and Angular Spread (AS) estimators are compared. A single source transmitter through a Rayleigh channel scenario is considered. First, the Maximum Likelihood (ML) estimator is studied. Then, low-complexity estimators which are the Spread Root-MUSIC and the two-stage approach, are presented. Simulation results show that the ML offers lower error estimation while the other estimators present a good compromise between computational complexity and estimation accuracy.