Conveners
2.3 Slow-Wave Devices
- Nick Jordan (University of Michigan)
The results of an experimental investigation of a relativistic backward wave oscillator (RBWO) in E-band are presented. An overmoded slow wave structure (SWS) was designed to generate a higher order mode (TM03) at 78GHz.1 Rectangular corrugations were used for the SWS having surface waves with upper cutoff frequencies above 90 GHz (E-band). The characteristics of this millimeter wave source...
Calabazas Creek Research, Inc. (CCR), in collaboration with, Communications & Power Industries, LLC (CPI) is developing a multiple beam triode for ion, proton, and electron accelerators. Traditional, high power triodes are limited to frequencies below 300 MHz and power levels less than 100 kW. Efficiencies exceeding 70% are routinely achieved and as high as 90% have been reported. This program...
Calabazas Creek Research, Inc. is developing a high efficiency, 1.3 GHz, 100 kW klystron for driving accelerators. The goal for the efficiency is at least 85%. Designs for the RF circuit, electron gun and collector are presented.
Using the COM design method for klystrons put forth by [1,2] (COM: Core Oscillation Method), CCR has created a design with an efficiency of 82%, as calculated...
The Multi-Frequency Recirculating Planar Magnetron (MFRPM) [1,2] is a novel high power microwave (HPM) source designed to generate two frequencies simultaneously. The MFRPM is capable of producing MW power levels near 1 GHz and 2 GHz with an L-Band Oscillator (LBO) and S-Band Oscillator (SBO), respectively. The MFRPM is the first magnetron to demonstrate harmonic frequency locking, wherein the...
A recent treatment of a thin tape helix traveling wave tube (TWT) yielded an exact hot tube dispersion relation [1]. This work modified Pierce’s classical theory by introducing a new parameter, “q”, which accounts for space charge effects on the phase velocity of the circuit mode. This is analogous to the familiar Pierce space charge parameter, Q, which accounts for the space charge effect on...
The new 2D code TESLA-Z [1] was developed at the US Naval Research Laboratory as a tool for geometry-driven large-signal modeling of linear-beam vacuum electronic devices (VEDs). The modeling approach is based on the representation of VED’s structure as a generalized network of ports (including actual input/output ports and interaction gaps) whose frequency dependent properties (response) can...
An electron gun is being designed for an amplifier at Ka-Band that requires a sheet beam with a 3 to 1 (width-to-height) aspect ratio. The design process includes running MICHELLE simulations manually for “one at a time” iterations of the gun geometry, and also “many at a time” MICHELLE simulations using automated optimization tools. We run MICHELLE, a charged particle beam optics code [1,2],...
Two dimensional (2D) periodic surface lattices PSLs [1-6] have applications in both fast-wave sources [1] and slow-wave sources [4]. Analytical theory and numerical PIC simulations have been used to design an electron beam driven W-band millimeter-wave oscillator, in which a cylindrical two dimensional (2D) periodic surface lattice (PSL) forms an over-sized mode-selective cavity. The 2D PSL...
