Microwave and millimeter-wave high-power vacuum electron devices (VED) represent a modern technological continuation of one of the original and basic building blocks of RF electronics technology. Based on original vacuum tube (valve) principles that date from the turn of the 19th to 20th centuries, these present-day incarnations couple modern design and manufacturing techniques to produce reliable high-performance RF power devices.

“Vacuum electron devices may at first seem anachronistic,” says ABI Research director Lance Wilson. “But in some cases there is no other way to generate such levels of RF power within an acceptably small space. Certain klystrons and gyrotrons can generate megawatts, and it would take tens of thousands of transistors to do that.”

Surprisingly these so-called “dinosaurs,” far from being an endangered species, are essential elements in specialized military, scientific/medical and space communications applications. And as such the market for them is, in Wilson’s words, “extremely large, much bigger than you might think.”

Despite the durability of this technology, a new solid state solution does have the potential to disrupt at least part of this market. Gallium nitride has emerged as the basis for semiconductor devices that could replace at least some microwave and millimeter-wave VEDs. This technology has the required very high frequency (up to 50 GHz) performance, combined with a very high power capability similar to that achievable by silicon LDMOS.

“Many consider gallium nitride as a possible successor to microwave tubes, especially the lower-powered traveling wave tubes,” notes Wilson. “But opinions differ about the depth and timing of this threat to the status quo.”

This market has always been under-reported, and poorly understood by those not directly involved. ABI Research has now addressed that lack with a new study, “Microwave and Millimeter Wave High-Power Vacuum Electron Devices and the Gallium Nitride Threat.” This report examines the microwave and millimeter-wave high power vacuum electron device market and assesses how emerging gallium nitride (GaN) devices could affect that business. It will be of interest to organizations involved in defense electronic, energy and scientific research, and spacecraft electronics, as well as VED manufacturers, RF power semiconductor users and manufacturers, and government.