The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This article presents the investigation of millimetre wave extended interaction oscillation (EIO) using both pencil and sheet-shaped pseudospark (PS)-sourced electron beams. A W-band (75–110 GHz) pencil beam Extended Interaction Oscillator (EIO) was designed and constructed to operate for the first experiment with the output power of 38 W achieved from a four-gap PS discharge operating at 30.5 kV...
This article presents the investigation of a millimetre-wave extended interaction oscillation using both pencil and sheet-shaped pseudospark (PS)-sourced electron beams. Two W-band (75–110 GHz) pencil and sheet beam extended interaction oscillators (EIO) were designed and constructed respectively. The PS-sourced pencil beam EIO structure was firstly driven by a four-gap PS discharge operating at 30...
This article presents the investigation of millimeter wave extended interaction oscillation using both pencil and sheet-shaped pseudospark (PS)-sourced electron beams. A W-band (75–110 GHz) pencil beam extended interaction oscillator (EIO) was designed and constructed. In the first experiment the output power of 38 W was achieved from a four-gap PS discharge operating at 30.5 kV. PS-sourced beam generation...
High quality intense electron beams play an important role in high power millimeter-wave and terahertz radiation generation. To this end, the pseudospark-sourced electron beam has been investigated with their applications in different beam-wave interaction structures. Different structures have been designed and modelled using the particle-in-cell codes MAGIC and CST Particle Studio. The experimental...
Pseudospark (PS) electron beams of outstanding performance have been studied recently with their application to a demanding field of millimeter-wave and terahertz radiation generation. To this end, the PS discharge process itself has been studied and millimeter wave sources which utilize a PS sourced electron beam in different beam-wave interaction structures have been designed and modelled using...
The pseudospark discharge is a form of low-pressure gas discharge capable of generating extremely high currents with short rise times by means of a unique hollow cathode structure [1-6]. A high-quality electron beam is generated during the later phases of the discharge process, which possesses high current density and brightness, as well as the ability to self-focus via ion channel focusing. This...
Millimeter-wave radiation has been successfully generated by a ∼100GHz BWO driven by a high brightness electron beam derived from a 14-gap pseudospark discharge. Pseudospark electron beams have been studied recently with their application to millimeter-wave and terahertz radiation generation. A BWO utilizing the interaction between an axial electron beam and a slow-wave structure was designed and...
Cold test results of a G-band sheet beam backward wave oscillator (BWO) with a double grating waveguide, fabricated by wire cutting and a 3D printing technique, are presented in this paper. The dispersion curve and S-parameters of the BWO slow wave circuit and Bragg reflector were measured and the results compared to the numerical modelling and analytical theory.
This paper presents the latest results from a second harmonic gyro-TWA experiment at Strathclyde University. The experiment uses a helically corrugated interaction region and operates at Ka-band. Simulations have been performed to predict the amplifier gain and bandwidth using linear theory. Amplifier stability margin can be improved with the addition of a sever. A sever has been designed and manufactured,...
Latest results from a second harmonic gyro-TWA experiment at Strathclyde University are presented. The Ka-band experiment uses a helically corrugated waveguide. Simulations have been performed to predict the amplifier gain and bandwidth. The simulations are compared to laboratory measurements of the cold waveguide dispersion using a new, improved design of polarization converter.
Gyrotrons find use in several diverse fields, ranging from plasma heating and plasma diagnostic to spectroscopy and materials processing. However, with demand for high power coherent radiation at THz frequencies, the confining magnetic fields required for gyrotrons operating at the fundamental harmonic become increasingly restrictive. However, considerable promise lies with the concept of the gyro-multiplier...
Electron cyclotron radio emissions, known as Auroral Kilometric Radiation (AKR) originate in the X-mode from regions of locally depleted plasma in the terrestrial polar magnetosphere. A laboratory experiment was constructed to study the emission mechanism of AKR scaled to microwave frequencies [1-2]. 3D PiC simulations of the experiment were conducted to study resonant energy transfer with nonazimuthally...
A quasi-optical corrugated horn has been constructed for a W band gyro-TWA1,2 based on a cusp electron beam source3–5 with a helically corrugated interaction region6–8. The design is intended to provide an effective method to decouple the radiation and the beam so that a depressed collector energy recovery system may be used9–11. The horn converts a cylindrical TE11 mode into a free-space TEM00 mode...
A small-scale pseudospark discharge is being investigated as the electron beam source for a klystron operating at a frequency of 94 GHz, and single-gap discharge experiments have been carried out. The klystron has been designed using the particle-in-cell (PiC) code MAGIC-2D and simulated output to date looks promising.
An experimental simulation of the Earth's Auroral Magnetosphere has been created. Experiments have been undertaken to study the processes by which the auroral cyclotron maser emission occurs.
A small-scale pseudospark discharge is being investigated as the electron beam source for a klystron operating at a frequency of 94 GHz and single-gap discharge experiments have been carried out. The klystron has been designed using the particle-in-cell (PiC) code MAGIC-2D and simulated output looks promising.
The Terahertz band of EM spectrum has received considerable research interests recently. A micro-klystron has the potential to meet the requirement of high power and compact terahertz source in many applications. The micro-klystron needs a very thin electron beam with sufficient current density. A pseudospark discharge cathode has the ability to provide high current density with small diameter electron...
The experimental demonstration of a gyrotron backward wave oscillator (gyro-BWO) using a cusp electron gun and helically corrugated waveguide will be presented. Operating in the W-band frequency range the gyro-BWO is predicted to output ~10 kW with a frequency tuning range of 85-104 GHz at 18% electronic efficiency before the energy recovery. The annular axis-encircling electron beam has been experimentally...
Summary form only given. Terahertz radiation, which ranges from 0.1 THz to 10 THz, has received substantial interests in recent years. The conventional vacuum electronics technology has the potential to supply high enough powers to underpin many exciting and emerging THz applications. Klystrons have been designed to generate THz radiation. This vacuum device requires a very small sized RF circuit...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.