The imminent, widespread adoption of 5G promises a new age of wireless network technology. However, current mobile technology infrastructure is still waiting on a handful of modifications before 5G becomes widespread. A team of Holonyak Lab researchers are working toward a solution.

Holonyak researcher Yansong Yang awarded Best Paper for work on 5G filter

The imminent, widespread adoption of 5G promises a new age of wireless network technology that feels a lot more like the sci-fi “future” that has been so classically envisioned. This modern empire expects to be able to support mobile virtual reality and augmented reality, self-driving cars, remote surgery, a booming Internet of Things, and more. However, our current mobile technology infrastructure is still waiting on a handful of modifications before 5G becomes widespread. A team of researchers from the Illinois Integrated RF Microsystems Group under Songbin Gong are working toward a solution.

Yansong Yang
Yansong Yang
To address the upcoming deficit in 5G framework, the group assembled to explore some of the front-end issues that arise when current technology tries to utilize 5G networks. Their research, “A C-band Lithium Niobate MEMS Filter with 10% Fractional Bandwidth for 5G Front-ends,” earned lead researcher Yansong Yang a Best Paper award by the 2019 International Ultrasonics Symposium in Glasgow, Scotland last month.

“Our goal was to contribute to the 5G revolution,” Yang, a Holonyak Lab student, shared, “Our focus was to break the current bandwidth limitation by achieving the wider bandwidths necessary for 5G front-end in the same compact footprint sported by current technology.”

5G will require a higher data rate in the higher frequencies, which the current frequency bands, operated by companies like T-Mobile and AT&T, do not have the space for in their current bandwidth

Yang compared the need for greater bandwidth to widening a highway. Telecommunications companies can go through the trouble to widen the highway – expand the bandwidth to allow for a higher data rate – but a successful implementation of the new flow must also consider the destination on the receiving end of all this increased traffic to avoid a bottleneck effect, the terminal stop being handheld devices like smart phones. Smart phones have filters that place limitations on the size of the bandwidth they can accept. The Gong Research Group’s work offers a first demonstration of a new class of filters that accommodate the largest fractional bandwidth achieved for acoustic-only filters at 5G frequencies.

Songbin Gong
Songbin Gong

The road to this point has not always been smooth, though, and Yang has faced discouragement in the past.

“Months ago I presented similar work at a conference, only to have a respected researcher in the field contact me afterward,” said Yang. “They expressed their concern that I was taking the wrong approach with my research. But our group has clearly demonstrated that this research is a step in the right direction.”

Helping to co-author the study were Holonyak Lab postdoctoral researcher Ruochen Lu, grad student Liuqing Gao, and Associate Professor Songbin Gong. The project was funded through grants awarded by both the National Science Foundation and the U.S. Defense Advanced Research Projects Agency.

While further changes to our infrastructure will be needed to make room for 5G technology, Yang believes this is a great foundation and is excited about the vast room for improvement and growth in this emerging area.