IEEE Radio and Wireless Week Panel: Getting to D-Band is a Group Effort
At IEEE Radio and Wireless Week 2023, industry leaders in chip fabrication and measurement engaged in a panel discussion to give engineers their opinions on the future of D-band technology.
Hoping to answer pressing questions regarding the next step up in high-frequency technology, industry experts gathered for a panel at last week’s IEEE Radio and Wireless Week 2023 to answer burning questions from researchers and designers on the road to D-band. All About Circuits was at the event to cover the panel.
Representatives from semiconductor and measurement companies answered engineers' questions regarding their feelings toward D-band, and how their organizations may bring it into the mainstream. All About Circuits image
As the wireless industry races toward higher and higher speeds, the potential for the D-band (110 GHz – 170 GHz) to provide higher bandwidth has the industry feeling mixed emotions regarding the future.
The panel, entitled “The Road to D Band is Full of Good Intentions”, was moderated by Roberto Quaglia, Cardiff University, UK and Vittorio Camarchia, Politecnico di Torino, Italy.
- Chris Sanabria, Qorvo
- Harris Moyer, HRL
- David Danzilio, WIN Semiconductors
- Remy Leblanc, OMMIC
- Valeria Brunel Di Giacomo, UMS
- Eduard Preisler, Tower Semiconductor
- Jon Martens, Anritsu
- Marcus DaSilva, National Instruments
- Gerhard Schoenthal, Virginia Diodes
On one hand, test equipment manufacturers and semiconductor foundries pushing toward higher frequencies will give designers more spectrum access, but on the other, the daunting challenge of >100 GHz technology has manufacturers reevaluating their own goals, and whether the demand for D-band is enough to justify the required R&D efforts.
This article offers a summary of the panel to give readers the newest information from some of the leading manufacturers and foundries in regard to the unique challenges imposed by D-band electronics, as well as the outlook from the point of view of the panelists.
Unique Challenges in the D Band
The challenges imposed by the D-band can be summarized quite succinctly by the introductory quote from Eduard Preisler from Tower Semiconductor, who said, “I mean, you’ll get some gain at 150 GHz.” As frequencies inch higher, the technology that has formed the backbone of the microwave community suddenly becomes obsolete, with standard transistors offering less in the form of gain.
The electromagnetic spectrum shows the location of the D-band, making it a major step up from the current state-of-the-art W-band electronics. Image used courtesy of RadarTutorial
In addition to the reduction in performance, a key metric for the future of D-band technology is predicted to be power density. When electronics become smaller (especially after taking a hit to performance), the amount of power dissipated can grow as the device area shrinks, creating a rapid rise in power density.
If left unaddressed, this can create critical device failures that hamper the reliability of D-band electronics. Gerhard Schoenthal from Virginia Diodes said, “If you can’t get the heat out, then there are those kinds of practical problems that help distinguish where this technology goes.”
D-band Isn’t a Solo Effort
Depending on who is asked, there are several answers for who will be the first to break into the D-band. This answer will be much clearer as specific applications emerge, but one thing is certain: the road to D-band won’t be lonely.
Early in the panel, Gerhard Schoenthal said, “As the test and measurement guys get better and better, it’s going to enable [semiconductor foundries] to do more. The models and the test and measurement techniques will evolve together.”
An example graph showing power density versus feature size highlights an expected problem for D-band electronics, as high temperatures impact reliability and performance. Image used courtesy of University of Virginia
Regardless of what sector is the “first” to use the D-band spectrum, meaningful developments will require the combined effort of foundries and T&M to provide designers with the materials, kits, and measurement devices to design the next generation of wireless devices.
The Future of D-Band
Designers shouldn’t expect to have their hands on D-band electronics or test equipment anytime soon, as was highlighted by David Danzilio of WIN Semiconductors. “Is there business right now in D-band? No, but that will happen.” At the present level of demand, both semiconductor and T&M companies have no incentive to produce D-band equipment, because there is simply not a large market to justify the extensive R&D costs.
As wireless technology continues to evolve, however, it will also be interesting to see the evolution outside of raw frequency increases. Gerhard Schoenthal looked back on a time when a group sticking to lower frequencies but focused on optimizing communication protocols was able to outperform the latest and greatest technology, opening the possibility of further performance increases outside of higher-frequency electronics.
For every major advancement, a new way of thinking is required, and while achieving D-band performance will likely require brilliant engineers, it may also require what Roberto Quaglia called “diligent, stupid people” to help designers think outside the box and start with a clean slate to usher in a new era of communications technology.