VFTT – Plextek RFI

VFTT – Plextek RFI

Liam Devlin, CEO, Plextek RFI

MPD: Millimeter wave frequencies will be used for cellular communications for the first time in 5G. What challenges and opportunities does this present for the microwave industry?


We have developed mmWave components for most of the favored candidate mmWave 5G bands (26 GHz, 28 GHz, 37 GHz and 39 GHz). The challenges are a combination of meeting the cost target and achieving the required functionality and performance in a compact footprint. While early mmWave 5G terminals for applications such as fixed wireless access might withstand a higher unit cost, when the technology is adopted for high volume consumer terminals low cost will be critical. All of the mmWave 5G systems we have worked on have included some form of beam steering with multiple mmWave front-end paths. This makes the technical requirements more challenging, and adds to the difficulties of meeting size and cost targets. High levels of mmWave integration are the key to meeting all of the goals.

The opportunities for mmWave component suppliers are clear — if they develop the right product they will have the opportunity to supply huge volumes as terminal equipment sales ramp up. Working with the right system partner is key to achieving this. For mmWave design houses such as Plextek RFI, we’re already benefiting from the opportunities that 5G provides, as the availability of experienced, proven mmWave design resources is limited and the demand for these skills is strong and growing.

MPD: What RF and microwave technologies do you feel will have the greatest impact in our industry overall between now and 2020? 


The operating frequencies to which CMOS technology is pushed will continue to rise, increasing the availability of highly integrated mmWave components. I expect GaAs technology to still dominate for front-end components requiring high linearity or low NF; the development of the GaAs MMIC processes is also continuing, providing improved performance and allowing the integration of multiple device types. We’ll start to see the emergence of mmWave GaAs processes containing E-mode PHEMTs, D-mode PHEMTs and PIN diodes all on the same MMIC.

The use of GaN technology will also continue to grow. It has proven capability for high power RF and microwave amplifiers and we’re now starting to see increased availability of GaN components operating at mmWave frequencies. Many commercially available GaN amplifiers focus on providing high levels of saturated output power, and I believe we’ll see increasing availability of GaN amplifiers designed for applications requiring high linearity such as cellular backhaul, 5G (initially sub-6 GHz, but ultimately mmWave 5G too) and satellite communications. We’ll also see increased adoption of GaN transistors in place of LDMOS for cellular base station PAs.

MPD: After years of hype and little to show for it, IoT networks are actually being deployed in a variety of applications. Do you believe IoT is a major opportunity for the RF and microwave industry? If so, why and if not, why not?


I’ve been telling people for years that IoT is already here. As I look out the window of my office, every street light in this area has a transceiver providing wireless connectivity. Many vehicles in the UK include transceiver units that monitor the behavior of the driver in real-time and transmit it back for data processing. One of the main applications for this equipment is for insuring young drivers, but similar products are used for fleet management of commercial vehicles. Many utility companies now offer smart meters, which send electricity (energy) or gas usage data back to the supplier in real time, and also allow consumers to reduce their energy consumption by showing them which appliances are drawing the most current. These are examples of IoT that have been active for a number of years, and already make use of RF components. What is now set to grow is the use of cellular technologies for IoT applications, as new low-power protocols such as NB-IoT (4G) are adopted, and later 5G. Both massive IoT and mission-critical IoT are key use cases for 5G—the former because of the sheer capacity of devices that will be deployed, and the latter because such applications will require very low latency. As the applications for IoT continue to grow, so will the opportunities for the RF and microwave industry.

MPD: We believe that the defense industry will retain its crucial importance to the RF and microwave industry regardless of overall DoD budget constraints. Do you agree with this statement? Either way, please explain your reasoning.


I do think that defense applications will continue to be of crucial importance to the RF and microwave industry. Over the past 18 months around 25% of our business has been from defense contracts. The work we’ve been doing has been mainly custom GaAs and GaN MMIC developments. This has been in part to benefit from the size and cost advantages of an integrated solution, but we’ve also developed components with functionality that’s not commercially available to allow the development of innovative new systems. Defense capability needs to continually evolve to stay ahead of the game, and this will ensure continued future opportunities for the RF and microwave industry.