Beam Steering of a Multi-Port Chassis Antenna Using the Least Squares Method and Theory of Characteristic Modes

Abstract

This communication aims to obtain the maximum gain of a multi-port chassis antenna at the desired direction. The beam steering algorithm provides the weighting vector for the multi-port antenna to achieve the above goal. This communication uses the conventional least squares (LSs) method and the theory of characteristic modes (CMs) to find the efficient beam steering algorithm for a multiport chassis antenna. Owing to orthogonal properties of the CMs, the following two advantages emerge: 1) the algorithm provides a simple LS solution without computation of matrix inversion and 2) the physical meaning of this simple LS solution is equivalent to the narrowband time-reversal processing, i.e., phase conjugation processing. Consequently, the proposed algorithm makes it possible to efficiently control the radiation pattern of the multiport antenna in the desired direction with any kind of desired polarization. Validation was conducted by applying the proposed method to an insect-like drone model having three CMs.