A multigigawatt X-Band relativistic backward wave oscillator with a modulating resonant reflector

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

“…The output microwave signal was received by an open-ended rectangular waveguide with cross section of 47.6 × 22.2 mm 2 . The rectangular waveguide is 50 cm long, and the outer wall of the waveguide was pasted with absorbers in order to decrease the frequency dependence of the effective section (Klimov et al, 2008;Zhang et al, 2009). The receiving antenna was situated at a distance of 9 m away from the phase center of the radiation horn.…”

“…As shown in Figure 5, the maximum electric field appears in the middle position, not on the corner wall, as is the case in the TM 020 reflector that is generally used in previous BWO-RR (Klimov et al, 2008;Li, 2008), which could increase the power handling capacity. Moreover, similar to the klystron, the self-field of the intense beam can provide significant electrostatic insulation against vacuum breakdown at the extraction cavity (Friedman et al, 1990).…”

“…Based on super radiance, ultrashort X-band pulses of about 3 GW peak power and 0.6-0.7 ns width were produced with a power conversion efficiency of 150-180% (Eltchaninov et al, 2003). In 2008, a microwave power of 4.3 GW with efficiency of 31%, and power of 5 GW with efficiency of 22% were obtained in an X-band BWO with a modulating resonant reflector (Klimov et al, 2008). In China, a power of 4.1 GW and efficiency of 26% was reported in a relativistic extended-interaction-cavity oscillator (Huang et al, 2008).…”

Experimental investigation of a Ka band high power millimeter wave generator operated at low guiding magnetic field

“…Among various HPM sources, slow wave type devices [3][4][5][6][7][8] are very attractive for their high efficiency and high stability, which are mainly due to the following two reasons. First, with the help of the guiding magnetic field, electron beams of high quality could be obtained, which can achieve better beam wave interaction with the slow wave structures (SWSs).…”

Improved power capacity in a high efficiency klystron-like relativistic backward wave oscillator by distributed energy extraction

“…2,3 Later, the cutoff neck is replaced by a resonant reflector, which also provides a pre-modulation of the electron beam, and the maximum axial electric field and harmonic current appear in the middle position of the SWS, increasing the efficiency to about 30%. [4][5][6] The klystron-like RBWO combines the transition radiation with Cherenkov radiation, in which the introductions of the modulation cavity and extraction cavity increase the axial electric field and harmonic current at the end of the SWS and in the extraction cavity, and the efficiency is enhanced to about 50%. [7][8][9] Moreover, adding two pre-modulation cavity before the resonant reflector further improves the axial electric field and harmonic current in the extraction cavity, and the efficiency can be up to 57%-70%.…”