Home > News > Novel RF Switch Technology from NDEE Making Traction in 5G and 6G Wireless Movement

Novel RF Switch Technology from NDEE Making Traction in 5G and 6G Wireless Movement

Leslie Lestinsky • DATE: September 19, 2019

Society is about to enter the 5G era, with eyes already on 6G possibilities. This movement will ripple profound economic and technological waves.

In March 2019, the Federal Communications Commission opened the spectrum above 95 GHz for experimental usage to encourage technology breakthrough in next generation communications.

High performance integrated RF switches in this frequency band have the potential to boost a variety of new applications. This in turn will meet current market demands and enable unique functionalities in circuits and systems. They can provide advanced sensing, imaging and beyond 5G communications.

The current state-of-the-art, solid state switches are bound by what electrical engineers currently know about the nature of their electromagnetics, amongst other practical constraints. These switches are not yet apt to operate at mmW-THz frequencies (30 – 300 GHz and beyond). Their low switch intrinsic figure-of-merit (FOM), high insertion loss, and low on/off ratio, blocks progress. Also, micro-electro-mechanical systems (MEMS) based switches are limited by their complicated fabrication process and difficulties in large-scale integration.

RF Diagram
Shi's diagram of the team's high-performance optically controlled integrated RF switches.
Department of Electrical Engineering (NDEE) graduate student Yu Shi, has been working on navigating past this dilemma and harnessing the opportunity of the expanded spectrum. His team, advised by NDEE professor Lei Liu, have proposed a novel class of high-performance optically controlled integrated RF switches based on photo-induced free carriers in semiconductors.

By studying the device geometry and structure, they found that a record high FOM of 184 THz can be achieved using germanium switches.

In addition to achieving high performance via ultra-low insertion loss and high isolation, the proposed RF switches also offer advantages such as compactness, easy fabrication and integration, high operation speed, and high reliability. These switches demonstrate promising possible applications in tunable/reconfigurable mmW-THz circuits required for advanced sensing, imaging and beyond 5G communications. 

The team’s paper “High-Performance Optically Controlled RF Switches for Advanced Reconfigurable Millimeterwave-to-THz Circuits” was awarded Best Student Paper (first place) at the Institute of Electrical and Electronics Engineers (IEEE) International Microwave Conference on Hardware and Systems for 5G and Beyond.

“I am very pleased to know that Yu has won Best Student Paper Award at the IEEE IMC-5G 2019 Conference,” said Liu. “The novel RF switching technology we proposed, and Yu is working on may find a broad range of applications (e.g., switching network in 6G cellphone or base station) and enable a new class of tunable/reconfigurable circuits for beyond 5G or next generation adaptive wireless communications."

The group has also recently won the prestigious IEEE MTT-S THz prize for their paper on 740 GHz beam-steering and forming antennas that could also be applied in future adaptive wireless communications.

“Winning this award is really encouraging,” said Shi. “It could not have been done without Prof. Liu’s guidance and my group members’ support.”