An Improved Modulation Module in Time-Modulated Array

An improved modulation module for beam steering in time-modulated array (TMA) is presented and investigated. The general improved module deploys parallel submodules consisting of several delay lines and imposes proper time delay to each submodule, enabling simultaneous improvement of modulation efficiency and allowed radio frequency (RF) signal bandwidth when utilizing the first positive harmonic for beam steering. Analysis of equivalent time sequence, modulation efficiency, and allowed signal bandwidth are provided, followed by several simulations of signal transmission and harmonic beam steering. Compared to the state-of-the-art TMAs, the proposed module shows obvious advantages on the modulation efficiency, especially on the remarkable allowed signal bandwidth when considering the limit of switching speed in RF switches.