WSL: Frontiers of G-Band Innovation for Next-Generation Communication and Sensing: From Ultra-High-Speed Devices to Sub-THz Integrated Circuits and Systems

Presentation Abstract
Increasing demand for continuous information flow and uninterrupted connectivity requires next-generation communication and sensing systems to support higher data-rates and wideband operation. As a result, wireless systems are moving to higher frequencies, offering wider bandwidth and higher channel capacity, while simultaneously reducing the system size. Although lower mm-wave bands, such as V-band (40–75GHz), have been explored as a potential solution to meet the demand for high-speed connectivity, the elevated levels of atmospheric attenuation create an additional challenge for maintaining signal power in wireless transmission over long distances. On the other hand, the upper portion of the mm-wave spectrum at 110–300GHz, also known as G-band, offers a promising path to achieve higher data-rates in point-to-point links, defense applications, localization, ranging, and other multi-user communication scenarios as the underutilized portion of the EM spectrum, while enabling higher resolution in radars and other sensing systems for biomedical or security screening and also reducing the size of all these systems. The sub-THz spectrum above 200GHz is of particular interest due to lower atmospheric attenuation. However, building high-performance integrated circuits and systems at G-band poses significant disadvantages due to the lower available gain of the transistors and higher noise contribution from components, leading to higher power consumption and reduced sensitivity at these sub-THz frequencies. Therefore, a combination of advanced circuit design techniques and system-level innovations, state-of-the-art high-speed devices harnessing the properties of compound semiconductors, heterogeneous integration, and co-design with packaging is essential to overcome the inherent challenges of the G-band design space. This workshop provides a comprehensive and in-depth review of the latest academic and industrial research on innovative techniques and cutting-edge technologies for realizing high-data-rate wireless communication and radar systems at 110–300GHz across SiGe, scaled-CMOS, InP, and GaN platforms, with particular focus on designs above 200GHz in the upper G-band. First, novel circuit techniques and topologies to enable high-power generation with maximum power efficiency, advanced high-speed device design and optimization in compound semiconductor processes, as well as III-V RF front-ends and hybrid InP/CMOS phased arrays above 200GHz, will be presented. State-of-the-art SiGe BiCMOS transceiver arrays across the entire G-band will be showcased with an emphasis on ultra-compact design and 2D scalability, along with multiple demonstrations of modular beamforming ICs supporting up to 200Gbps wireless transmission, wideband radar transceiver chips for integration in large MIMO arrays, and upper G-band MMICs enabling radar systems with multi-target resolution down to a few millimeters while maintaining an absolute ranging accuracy on the order of 1µm. In addition, system- and circuit-level design considerations for record-low-power CMOS radar sensor systems will be reviewed. Finally, co-design and co-integration of sub-THz ICs in SiGe and SOI with glass interposer technology and 3-D Heterogeneous Integrated (3DHI) phased arrays incorporating an antenna on glass, GaN-on-SiC MMICs, a silicon interposer, and a silicon Beam Forming Integrated Circuit (BFIC) will be presented as a pathway toward end-to-end communication modules in G-band for commercial and defense applications.