OTA Experiments on the Angular Accuracy of a Phase Monopulse AOA Antenna Using the Mean IQ-Value Method in a Rician Fading Channel

In this paper, we conduct investigations on the angular accuracy of a circularly arranged phase monopulse Angle of Arrival (AOA) estimation antenna in Rician multipath propagation environments. A novel algorithm, called the mean IQ-value method (MIQ method), is presented to extract true angular information about incident waves in a Rician fading channel, where the received signal is therefore composed of both random multipath scattered fields and a coherent line-of-sight (LOS) component. The experimental results using an Over-The-Air (OTA) fading emulator show that a high accuracy of angle estimation can be achieved using the proposed MIQ method, even in the case of a severe Rician fading channel, where a LOS component is extremely small, such as a Rice factor of K = -10 dB.