In this article, an ultrahigh repetition frequency sub-nanosecond pulse generator based on vanadium-compensated semi-insulating (VCSI) 4H-SiC photoconductive semiconductor switch (PCSS) under high bias electric field is presented. work, the 0.8 mm-thick PCSS was found to work with fields up 200 kV/cm and power capacity of 176 kW. The VCSI response test performed a 1 MHz, 1030 nm laser cluster driver configurable optical pulsewidth current viewing resistor (CVR) circuit. experiment, varied...

A frequency-agile microwave generating system is examined in this letter. Vanadium-compensated semi-insulation (VCSI) 4H-SiC photoconductive semi- conductor switch (PCSS) has been introduced to achieve wide-range frequency tuning. The output tuned by adjusting the pulse width of laser. Both simulation and experimental results show a tuning range 0.5 GHz 10.0 GHz. maximum operating power at 10 1.13 W, equivalent charging voltage 1.5 kV modulated light wavelength 1064 nm. Further experiment...

Vertical extrinsic photoconductive semiconductor switches (PCSSs) are presented with initial characteristics comparison between V-doped 4H-SiC and Fe-doped GaN PCSS under axial triggering such as dark resistance, photoconductivity, power output, breakdown behavior. Experiments carried out the 532-nm-wavelength laser mJ-level energy a pulse width of 30 ns. Photoconductive experiments show that photoelectric conversion efficiency is 2.27 times higher than same electric field strength different...

An X-band magnetically insulated transmission line oscillator has been investigated theoretically and experimentally in our laboratory. However, severe pulse shortening electrode erosion are observed the experiments. The theoretical analyses show that anode plasma formation load region is essential reason for erosion. In order to eliminate or at least minimize region, an improved beam dump presented. can be eliminated minimized dump.

The magnetically insulated line oscillator (MILO) is an attractive high-power microwave source. It a compact lightweight gigawatt-class coaxial crossed field device that needs no externally applied magnetic to insulate electron flow in slow-wave structure. An improved MILO model has been presented by Fan, Yuan and Zhong. A novel beam dump, one-cavity RF choke section, mode-transducing antenna are introduced into the MILO. In simulation, of TEM mode generated with peak power 4.2 GW, frequency...

In order to investigate the performances of repetition rate (rep-rate) operation an improved magnetically insulated transmission line oscillator (MILO), a series experiments are carried out on MILO device, which is driven by 40Ω, 50ns rep-rate pulser, TORCH-01. Polymer velvet and graphite cathodes tested, respectively, in experiments, whose diameters lengths same. The results experimental comparison between them presented paper. Both tested at electric field strengths about 300kV∕cm. applied...

A high-power photoconductive semiconductor switch (PCSS) working in linear mode can be used for RF generation by modulating the illuminating light. Such a PCSS constructed of semi-insulating 6H silicon carbide (6H-SiC) substrate and its characterization under high electric field is presented. The vertical structure, with one hollow/transparent electrode to let through laser light other highly reflective increase absorption. First, optimize high-voltage withstanding, factors affecting...

High-power photoconductive semiconductor switch (PCSS) working in linear mode can be used for RF generation by modulating the illuminating light. This letter presents a design and initial test of an optoelectronic class B push-pull microwave power amplifier (MPA) using two 6H-SiC switches. The tests have been conducted with bias voltage ±2.4 kV, at 80 kW peak laser pulse power, demonstrating that SiC PCSS produce microwaves. Then, circuit simulation is to study factors affecting electrical...

Radio frequency/microwave-directed energy sources using wide bandgap SiC photoconductive semiconductors have attracted much attention due to their unique advantages of high-power output and multi-parameter adjustable ability. Over the past several years, benefitting from sustainable innovations in laser technology significant progress materials technology, megawatt-class power electrical pulses with a flexible frequency P L microwave wavebands been achieved by semiconductor devices. Here, we...

A 1.2-GHz magnetically insulated transmission line oscillator (MILO) is investigated numerically and experimentally in this paper. Simulation optimization performed with the particle-in-cell code KARAT. When diode voltage current are 680 kV 53 kA, output microwave power 4.15 GW, frequency 1.169 GHz, efficiency 11.5%. In order to radiate a boresight peak pattern, TEM-TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> mode-converting...

The experimental results of the tunable load-limited magnetically insulated transmission line oscillator (TLMILO) are presented and discussed in this paper. In experiments, microwave frequency TLMILO can be changed arbitrarily range 1.337-1.760 GHz by changing tuner, tuning bandwidth is 13.6%. show that normal relative error frequencies between measured result simulation not more than 1.6%, mechanism does affect MILO's operation, maximum power efficiency 15.2%. demonstrate feasibility TLMILO.

An axial-triggering vertical SiC photoconductive switch with Al-doped ZnO placed under the Ag electrode is developed to enhance breakdown strength and photoconductivity. Traditional new devices AZO/SiC/Ag AZO/SiC/AZO/Ag structures, respectively, were prepared. Test results show that conductivity of device approximately 1.2 times higher than old one, attributable diffuse reflection effects AZO/Ag mirror. Under high bias voltages up 16.5 kV/mm a 30-ns pulse width laser input, shows...

Velocity saturation characteristics of a V-doped 6H silicon-carbide (SiC) photoconductive switch under high electric field are presented. A vertical-geometry device based on vanadium-compensated SiC is triggered by 532-nm laser pulse with light peak power several hundred kW and operational voltages from 2 to 20 kV. The maximum electrical achieved the up 1 MW (~50-A, 20-kV, 1.1-ns pulsewidth). When working voltage increased increase output power, carrier-velocity unavoidably impedes current...

An X-band magnetically insulated transmission line oscillator (MILO) is designed and investigated numerically experimentally for the first time. The MILO optimized in detail with KARAT code. In simulation, MILO, driven by a 720 kV, 53kA electron beam, comes to nonlinear steady state 4.0 ns. High-power microwaves (HPM) of TEM mode generated an average power 4.1 GW, frequency 9.3 GHz, conversion efficiency 10.8% durations 0–40 device fabricated according simulation results. experiments, when...

A compact relativistic magnetron with axial microwave radiation is experimentally investigated. Under the modified magnetic field distribution, only connecting a special horn antenna in direction, can stably radiate high power and efficiency microwaves. The total length of device ∼0.3 m, volume ∼0.014m3. In such working condition that applied voltage 539 kV ∼0.38 T, output ∼1.24 GW. Correspondingly, about 34.1%. radiating frequency 2.35GHz, which agreement π mode theoretical expectation.

Magnetic pulse compressors, based on magnetic switches, are considered as competitive candidates for high-voltage generation. It is generally believed that the lack of operating-parameter tunability these devices currently one crucial factors limiting their applications. In this paper, an adjustable high-power compressor, which deemed key component a power supply system, investigated theoretically and experimentally. Dominant parameters including compression ratio, saturation time, peak...

This paper provides a review of the compact intense electron-beam accelerators (IEBAs) based on liquid pulse forming lines (PFLs) that have been developed at National University Defense Technology (NUDT) in China. The history and roadmap IEBAs used to drive high-power microwave (HPM) devices NUDT are reviewed. properties both de-ionized water glycerin as energy storage media presented. Research into breakdown dielectrics desire maximize resulted invention several coaxial PFLs with different...

The SiC vertical photoconductive switch with an axial optical internal reflection trap to improve the ON-state performance is presented. extrinsic light absorption of vanadium (V)-doped low. As such used increase path and total absorption. consists a convex lens, silver mirror electrode hole, transparent create quasi-total structure. Simulation experimental evaluation reveal that both device's output current have been improved significantly. Compared regular illumination without reflective...

This paper reports the investigations of a dielectric filled relativistic magnetron with diffraction output (MDO) on frequency agile. The mechanism agile is theoretically analyzed. Particle-in-cell simulations and preliminary experiments prove analytics. In experiments, under working conditions, 605 kV 0.3 T, microwave 1.98 GHz, 200 MW radiated from an A6 type MDO when 95% Al2O3 ceramics total thickness 0.9 cm are filled. Compared 3.72 240 obtained without filled, S band to L achieved.

Magnetic switches could improve the stability, reliability, repetition rate, and life of pulsed power systems, based on which, a high power, low impedance, long pulse generator has been investigated numerically experimentally. The accomplishes compression forming at relatively voltage level, consisting core-type transformer, two-stage magnetic unit, impedance network, type main switches. A full circuit model was developed using PSPICE software to analyze key factors that influence output...

The competitive relationship between the surface flashover of coplanar electrodes and body current channel was investigated. Breakdown behavior GaAs photo-conductive semiconductor switch (PCSS) with a backside-light-receiving electrode structure studied in this paper. PCSS triggered by laser pulse an extrinsic absorption wavelength 1064 nm. Special insulating construction designed for PCSS, while encapsulated transparent adhesive. Our first set experiments at bias voltage 8 kV, breakdown...