User Tracking and Wireless Digital Transmission through a Programmable Metasurface

Abstract

User tracking has been an important aspect in wireless communications. Commonly, distributed apertures such as array antennas or multiple sensors are needed in wireless communication systems to achieve spatial resolutions for user tracking. Here it is proposed to realize the user tracking and wireless digital transmission simultaneously by using a single metasurface aperture. The reflection‐type metasurface consists of many subwavelength binary reconfigurable units. By programming these binary units, the metasurface can steer waves radiated from a horn antenna to a specified direction with different digital radiation phases. With this function, the metasurface can track the users by steering directional beams and transmit phase‐modulated digital signals through the directional beams. A prototype based on a programmable metasurface is developed and experiments in terms of cyclic redundancy check (CRC) and constellation diagrams are performed. The measured results prove that the user tracking and wireless digital transmission can be integrated through the programmable metasurface. Considering the simple architecture and flexible controlling features, the proposed methodology has great application prospect in integrated radar‐communication systems and cognitive electronic systems.

Recent Progress in Reconfigurable and Intelligent Metasurfaces: A Comprehensive Review of Tuning Mechanisms, Hardware Designs, and Applications

“…Such programmable metasurfaces have been extensively implemented in several applications such as imaging, [74,75] holograms, [41,76] beam focusing, [77,78] beam steering, [70,[79][80][81][82][83][84][85] and wireless communication. [86][87][88][89][90][91][92][93][94][95] To realize smart control of EM waves, programmable metasurfaces have been used to develop intelligent metasurfaces with self-adaptivity, equipped with sensing and feedback components to control their reprogrammable functions without human intervention. [96][97][98][99][100] Space-gradient metasurfaces are constrained by time-reversal symmetry and Lorentz reciprocity that can be overcome by introducing a temporal gradient metasurface.…”

Broadband and Programmable Amplitude-Phase-Joint-Coding Information Metasurface

“…In 2014, the concept of digital coding metamaterial was proposed, which makes a bridge linking the physical world and digital information world and has attracted great attention in recent years. − More importantly, the coding sequence can be encoded in a programmable way by loading active components into the unit structures, so as to realize the real-time manipulation of EM waves, resulting in programmable metamaterial and metasurface. Generally, most of the programmable metasurfaces are based on phase coding that have been widely used to realize dynamic holograms, wireless communications, reconfigurable intelligent surfaces (RIS), and so on. − Some programmable amplitude-controlled metasurfaces have also been proposed to control the EM energy of reflected and refracted waves , or to make the energy conversion between the transmission, absorption, and reflection modes. − However, the phase-coded metasurfaces usually can only tailor the wavefronts of EM waves, while amplitude metasurfaces usually can control the energies of EM waves, both of which have their own limitations in manipulating the EM waves. Most recently, to achieve more degrees of freedom of EM manipulations, some reconfigurable amplitude-phase-controlled metasurfaces have been designed to realize simultaneous controls of the amplitude and phase of EM waves. , However, these metasurfaces either have complex configuration by means of graphene or have small amplitude control range and narrow bandwidth …”

Joint Radar and Communication Empowered by Digital Programmable Metasurface

“…Massive researches about DPMs have emerged, such as computational imaging [19][20][21][22][23] and metasurface-based signal modulation and transmission. [24][25][26][27][28][29][30][31][32][33][34] Technically, DPMs are directly driven by digital signals and possess the characteristics of software and informatization, and hence are perfect platforms for combining the metasurfaces with electronic information systems. However, the intelligent level of DPMs is still limited, because the presented DPMs cannot simultaneously conduct internal decisions and exchange information with the external world.…”