Direction of Arrival Estimation using Positive and Negative Harmonics of Time-Modulated Array

Estimation of the received signal direction using time-modulated array (TMA) is getting more attention because of its inherent advantages of simple electronically controllable beamforming network. In this paper, two parameters based on the 1<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">st</sup> positive and negative harmonics of TMA with unipolar pulse sequence are employed to evaluate the direction of arrival (DoA) of the received signal and their performances over the feasible scanning range are investigated. It is observed that the parameter with negative harmonic component provides better accuracy in estimating DoA towards the positive side of the scanning range while the parameter with positive harmonic component is more precise towards the negative side. The numerical results corresponding to the accuracy of finding DoA in the form of root mean square error (RMSE) as obtained via Monte Carlo Simulation are presented and discussed.