Reconfigurable Linear Antenna Arrays for Beam-Pattern Matching in Collocated MIMO Radars

Abstract

Beam-pattern matching plays an important role in multiple-input multiple-output radars. In the vast majority of research done in this area, the aim is to find the covariance matrix of the waveforms fed into the transmit array. Also, reconfiguring a preset array of antennas (antenna selection), which means turning <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">off</small> some of the antennas in the array, is an effective technique to reach the desired beam patterns, dynamically. In this article, we introduce a novel multistep method to implement this reconfiguration technique to a uniform linear array. In each step, by exploiting the relation between the diagonal elements of a covariance matrix resulted from solving a beam-pattern matching problem and the transmitted power of the antennas, we find the least important antenna of the array and turn it <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">off</small> accordingly. Then, we repeat this process until a predefined number of antennas remains. Our proposed method outperforms its counterparts in the literature in terms of beam-pattern matching as well as computational complexity, which makes it an appropriate method for real-time applications. Simulations are used to show the validity and superiority of the proposed method.