Special Section Proposal Tunable Devices for Modern Communications: Materials, Integration, Modeling, and Applications

The tunability of devices is a prerequisite for modern communications: the next generation of systems operating at RF, microwave, millimeter-wave, THz, and optical frequencies requires operation over ultra-wide bands, fast switching between channels, and low noise, along with easy integration and low cost. With the advent of novel applications related to 5G and the Internet of Things (IoT), different technologies are being developed for answering these needs in the various frequency bands. In particular, new materials have been proposed, which allow device tunability at high frequencies, such as liquid crystals, ferroelectrics, atomically thin materials, and metamaterials. Novel tunable components and properties have been recently developed, in particular in the field of tunable filters and reconfigurable antennas. Furthermore, innovative integration technologies for the complete integration of millimeter-wave systems are gaining increasing interest, including substrate integrated waveguide (SIW) and circuit (SIC) technologies. In addition to the scientific and technological developments, new and efficient modeling & CAD techniques are required to design such components and systems, which guarantee reliable modeling, design flexibility, and fast time-to-market.