Evolution of mobile broadband is ensured by adopting a unified and more capable radio interface (RI). For ubiquitous connectivity among a wide variety of wireless applications, the RI enables the adoption of an adaptive bandwidth with high spectrum flexibility. To this end, the modern-day communication system needs to cater to extremely high bandwidth, starting from below 1 GHz to 100 GHz, based on different deployments. This instigates the creation of a platform called the Internet of Everything (IoE), which is based on the concept of all-round connectivity involving humans to different objects or things via sensors. In simple words, IoE is the intelligent connection of people, processes, data, and things. To enable seamless connectivity, IoE resorts to low-cost, compact, and flexible broadband antennas, RFID-based sensors, wearable electromagnetic (EM) structures, circuits, wireless body area networks (WBAN), and the integration of these complex elements and systems. IoE needs to ensure broader information dissemination via simultaneous transmission of data to multiple users through separate beams and to that end, it takes advantage of metamaterials. The precise geometry and arrangement of metamaterials enable smart properties capable of manipulating EM waves and essentially enable the metamaterial devices to be controlled independently to achieve desirable EM characteristics, such as the direction of propagation and reflection. This review paper presents a comprehensive study on next-generation EM devices and techniques, such as antennas and circuits for wearable and sub 6 GHz 5G applications, WBAN, wireless power transfer (WPT), the direction of arrival (DoA) of propagating waves, RFID based sensors for biomedical and healthcare applications, new techniques of metamaterials as well as transformation optics (TO) and its applications in designing complex media and arbitrary geometry conformal antennas and optical devices that will enable future IoE applications.

In this work, we propose a novel multiband meander line antenna that can operate at three different frequency bands and offer suitable performance for wireless body area network (WBAN) applications. The net geometry of the antenna is 36 × 30 × 1.524 mm${}^3$. The proposed low-profile antenna is analytically modeled and designed in full wave ANSYS HFSS using Rogers TMM4 as the substrate, followed by in-lab prototyping. The designed antenna resonates at 4.5 GHz, 5 GHz, and 5.8 GHz and maintains positive gain, efficiency, and acceptable specific absorption rates at each resonant band. The effectiveness of the antenna for WBAN applications is demonstrated using an in-lab manufactured phantom. The fabrication process of the phantom is described, and dielectric characterization of the phantom mimicking different human tissue layers is presented. Considering results with and without human body phantoms available in the full wave ANSYS HFSS tool, a comparative analysis between simulated and measured antenna parameters concludes this work. Both the simulated and measured results show good agreement.