Resonant, a start-up making filters for radio frequency front-ends, has acquired a filter supplier and hired the founder to direct its engineering efforts. It is an attempt at expansion for Resonant, which is riding the growing demand for filters in smartphones and other devices.
On Friday, Resonant said that it had purchased GVR Trade SA, a Swiss company that designs both surface and bulk acoustic wave filters. As part of the deal, the company's founder Victor Plessky will become Resonant’s director of engineering. Resonant also plans to hire some former GVR staffers.
Founded in 2012, the Goleta, Calif.-based company uses its Infinite Synthesized Networks software to configure and connect resonators, the building blocks of RF filters. It sells single-band duplexers but has been working on multi-band filters to relieve the growing complexity of smartphone front-ends.
In smartphones, filters tune into different frequency bands and reject interfering signals. This allows them to support multiple network technologies, including 3G, 4G, Wi-Fi, and Bluetooth. Their number in smartphones is growing with the introduction of LTE-Advanced and carrier aggregation, which rely on new combinations of spectrum.
“The more bands you have, the more filters you need,” said Christopher Taylor, an industry analyst for Strategy Analytics. Two years ago, smartphones contained an average of 35 filters but industry executive say that number could reach 100 in the next five years. In addition, smartphone makers are increasingly using high-performance BAW filters.
Resonant is far from the only company to sniff out the demand. This year, Qualcomm said that it would start manufacturing filters with Japan's TDK, with the option to buy the business after three years. Their new company, called RF360 Holdings, will compete with the same industry behemoths Resonant is up against, including Skyworks and Qorvo.
To compete, Resonant is betting on ultra-small filters that handle two or more frequency bands on the same chip. The company is trying to invent a new way to fabricate SAW filters, one that allows them to act like BAW devices. It is also working on reconfigurable filters that could replace multiple devices with a single tunable component.
If kept small and cheap, these mercurial devices "would be the closest thing to the holy grail," Taylor said. For now, Resonant has only demonstrated reconfigurable filters in the laboratory, while deep-pocketed companies like Broadcom and Qorvo are also struggling to crack the code.
Resonant paid around $1.1 million for Plessky's business and 22 advanced filter patents filed in the United States. Before he established GVR in 1996, Plessky worked as a project manager at Advanced SAW Products and as chief scientist for Thales Microsonics.
“Victor and his team add a tremendous depth of knowledge and meaningfully enhance our ISN suite of filter design tools and throughput capabilities,” said Terry Lingren, Resonant's chief executive, in a statement.