Target Localization Using Time-Modulated Directional Modulated Transmitters

TLDR: In this article , a target location scheme for multi-target localization in free space is proposed, which exploits the properties of directional modulated antenna radiation patterns which are synthesized using time-modulated arrays (TMAs).

Abstract: In this paper, a target location scheme for multi-target localization in free space is proposed. It exploits the properties of directional modulated antenna radiation patterns which are synthesized using time-modulated arrays (TMAs). Here, we show that the TMAs can be made to synthesize directional modulation (DM) symbols concurrently upon multiple angular beams. Compared with previous DM works on target localization, our proposed system exhibits some promising features, such a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${i}$ </tex-math></inline-formula> ) generating multiple beams simultaneously, enabling multiple targets detection at the same time along different angular directions, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ii</i> ) allowing multiple access in frequency domain, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">iii</i> ) requiring only one radio frequency (RF) chain with a signal peak- to-average power ratio (PAPR) of 0 dB; <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">iv</i> ) eliminating the azimuth ambiguity in mirror angular directions with respect to array boresight, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${v}$ </tex-math></inline-formula> ) flexibly adjusting the target angular resolution, and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">vi</i> ) enabling beam steering without the need of phase shifters. The proposed technique is useful in various applications, such as tracking and controlling multiple drones, vehicles, and etc. It provides an alternative means in most of the Radar applications, and with the capability of wireless communication, it can be treated in the domain of waveform design for the Integrated Sensing and Communication (ISAC).