Klystrons convert electron beam energy into radio frequency waves, often with significant amplification. Klystrons are configured as either oscillators or amplifiers. Their output power extends over a vast range, from a few watts to many megawatts. Klystrons are also very efficient, as high as 80%. But they have narrow bandwidth, i.e., they amplify only over a narrow frequency range. This limits their use in communications. Their primary application these days is for radar and in high-energy particle accelerators. Klystrons were one of the first microwave amplifiers to go above one gigahertz.

Our interest in klystrons extends back 25 years, to work on military radars for several aerospace companies. Recently there has been renewed interest in klystrons with multiple electron beams for accelerator applications. They are capable of delivering immense amounts of microwave power at lower beam voltages.

Another advantage of multi-beam klystrons is that they have much wider bandwidth. This opens the way for klystron use in communications. Based on this, we have applied for a patent on a broadband multi-beam klystron that utilizes electrostatic focusing.

Normally, multi-beam klystrons are focused with powerful magnetic fields, but this type of focusing is complex, expensive and adds considerable weight and size to the device. Our klystron design with electrostatic focusing is light, inexpensive and amenable to volume production. We have recently received a contract from NASA to build two of these devices. A photo of it is shown on the Projects page.

  Klystron from the 1970's  

If you need advice, components or a complete klystron design, don't hesitate to contact us.

Copyright 2005, ebeam, Inc.