Efficiency enhancement of a high power microwave generator based on a relativistic backward wave oscillator with a resonant reflector

Abstract

A high power microwave generator based on a relativistic backward wave oscillator with a resonant reflector (BWO-RR) has been proposed in order to improve microwave conversion efficiency. In this device, the slow wave structure is separated by a modulation cavity, which significantly decreases the energy spread of the modulated beam electrons. At the end of the slow wave structure, an extraction cavity is employed to increase the beam-wave interaction and optimize the extraction of the output power. Particle-in-cell simulations show that a microwave efficiency of 46% has been obtained compared with that of 34% obtained with the BWO-RR.

Efficient generation of multi-gigawatt power by a klystron-like relativistic backward wave oscillator

“…1) are displayed in Figures 2 and 3, which illustrate that in the klystron-like RBWO, the energy spread of the modulated beam electrons decreases greatly after the modulation cavity, and the wellmodulated electrons lose energy continuously (Xiao et al, 2009a). As shown in Figure 4, both the large amplitude and phase of the axial electric field in the extraction cavity are beneficial for further recovering energy from electron beam.…”

“…As shown in Figure 1, the basic distinguishing feature of the klystron-like RBWO compared to the RBWO-RR is the introductions of a modulation cavity and an extraction cavity (Xiao et al, 2009a). The modulation cavity separates the slow wave structure (SWS) into two sections, and the extraction cavity is added to the end of the SWS.…”

“…We have made great efforts to enhance the microwave power and efficiency (Chen et al, 2002;Liu et al, 2008aLiu et al, , 2008b, and presented a serious of HPM sources Teng et al, 2009;Xiao et al, 2008bXiao et al, , 2009aXiao et al, , 2009bXiao et al, , 2009cXiao et al, , 2010, among which the klystron-like RBWO that was proposed based on the RBWO with a resonant reflector (RBWO-RR) is extremely important (Xiao et al, 2009a). This article briefly outlines the physics analysis that reveals the possibility of increase in the conversion efficiency and power handling capacity and demonstrates the simulation and experiment results.…”

Design and Experiments of the Gw High-Power Microwave Feed Horn

“…14. TM 01 mode produced by BWO [29] was transferred by the mode convertor to TE 11 mode, which was radiated to air through the two-time flared circular horn with HMWPE window grooved periodically, and the inner pressure 0.1 mTorr was acquired by mechanical pump and molecular pump. SF 6 with pressure higher than 1atm.…”

High efficiency coaxial klystron-like relativistic backward wave oscillator with a premodulation cavity

“…[1][2][3][4][5][6][7][8][9][10][11] To further increase the beam-wave interaction efficiency and output power, in our earlier work we introduced a klystron-like RBWO combining transition radiation with Cerenkov radiation. [12][13][14] In that device, a resonant reflector was used before the slow wave structure (SWS) to reflect backward wave and premodulate the electron beam; a modulation cavity separated the SWS to decrease the energy spread of the modulated beam electrons; and an extraction cavity was added to recover energy from the beam. The beam dump was located very close to the extraction cavity to provide more kinetic energy for extraction.…”