We demonstrate the dual-band operation of a relativistic backward wave oscillator (RBWO) whose output is linearly polarized TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> -mode. The RBWO consists two cylindrical sections with sinusoidal corrugations where downstream section axisymmetric and upstream has combined left- right-single-fold spiral corrugations. show that generation 10 GHz realized when operates as BWO operating TM...

A study of the evolution wave dispersion in systems all-metallic periodic structures with increasing corrugation depth shows a similarity properties waves metamaterial slow-wave (MSWSs) and traditional metallic SWSs used high-power microwave sources. We show that main MSWSs, such as existence lowest order negative below cutoff, also appear ordinary deep corrugations. Furthermore, we find appearance is accompanied by hybrid mode being identified mode.

Two Cherenkov devices are effectively combined using a circular waveguide T-junction in simulation study. The microwave sources driven by the same high voltage pulser to prevent phase difference at output of power combiner. This passive combiner not only combines power, but also outputs Gaussian beam when TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">01</sub> mode is used as input. An efficient serpentine converter has been basis design...

Microwave sources transform the kinetic energy of an electron beam into microwaves through interaction electrons with a periodic slow wave structure (SWS). A metamaterial (MTM) waveguide is proposed for use in microwave oscillator instead conventional SWS that has been used long time to generate high power radiation. MTMs have interesting properties such as negative refractive index, low group velocity, and below cutoff propagation, among others. In this work, we study multibeam cathode set...

An X-band relativistic backward wave oscillator (BWO) is proposed to provide high-power Gaussian radiation that attractive for many applications. A Bragg reflector with combined single-fold left- and right-spiral corrugations of its wall was applied the cathode end interaction space. Such a converts operating TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">01</sub> -mode BWO forward TE xmlns:xlink="http://www.w3.org/1999/xlink">11</sub>...

The traveling wave tube (TWT) has been a reliable conventional vacuum electron device (CVED) since the 1940s. Researchers, beginning in late 1980s, extended TWT to relativistic beam regime generate 100- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{s}\cdot $ </tex-math></inline-formula> MW power notation="LaTeX">${X}$ -band. Since mid-1990s, there little advancement field. Recently, linear theory...

The output power of two Cherenkov devices is combined using a circular waveguide T-junction. microwave sources are driven by the same high voltage pulser to prevent phase difference in outputs. This passive combiner not only combines power, but also outputs Gaussian beam when TM <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">01</inf> -mode used as input. An efficient serpentine mode converter has been basis design. A conversion efficiency 85%...

We present the analysis of a microwave generator that uses two-spiral metamaterial (MTM) plates in below cutoff WR340 waveguide interacts with high-power electron beam, motivated by recent results obtained researchers at MIT. Particle-in-cell simulations using MAGIC code demonstrated power levels 12 MW are achieved backward wave mode frequency 2.47 GHz from an anomalous Doppler instability 1 μs pulsed beam energy 400 keV, current 82 A 415 G magnetic field. In addition, 9 output is 2.54...

A millimeter wave relativistic backward oscillator (RBWO) is proposed to provide megawatts of power with Gaussian output. An overmoded rectangular slow structure (SWS) a hollow electron beam was used increase the interaction impedance and avoid RF breakdown. The SWS can be fabricated more easily than sinusoidal one. RBWO consisting an axisymmetric generates 90 MW at 78 GHz. mode selection technique utilized select higher order as operating mode. corrugated waveguide converter convert TM <inf...

We numerically calculate using the 2-D electromagnetic solver SUPERFISH dispersion relation for modes supported by finite-length, overmoded, corrugated, cylindrical slow wave structures (SWSs) with azimuthal symmetry first enforcing electric, and thereafter magnetic boundary conditions on both left right boundaries of SWS. construct as a set curves related to azimuthally symmetric TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0n</sub>...

Backward wave oscillators are typically known to radiate in the TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">01</sub> mode. A two-spiral corrugated Bragg reflector has been used downstream of cathode an X-band relativistic backward oscillator (RBWO) a TE xmlns:xlink="http://www.w3.org/1999/xlink">n</sub> mode at output. Simple analytical formulas were design basic parameters reflector, which later optimized numerically since there is no...

For a relativistic backward wave oscillator (BWO) consisting of two cylindrical sections with sinusoidal profiles where one them is axially symmetric and the other has combined left- right-single-fold spiral corrugation, we demonstrate possibility generating TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> -mode linear polarization at single or dual frequencies using magnetic field decompression. Magnetic decompression, as shown in...

The importance of the Gaussian microwave beam is concentration maximum energy density along its axis. At open-ended corrugated waveguide, hybrid mode, HE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> , couples to fundamental free-space mode with almost no loss over wide bandwidths. Even though backward wave oscillator typically known radiate circular waveguide TM xmlns:xlink="http://www.w3.org/1999/xlink">0n</sub> modes, an asymmetric...

Summary form only given. Cerenkov high power microwave sources can be used to generate short, Gaussian pulses that are attractive for many applications. The backward wave oscillator (BWO) is typically known radiate the TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0n</sub> -mode in circular waveguide. signal usually extracted axially after reflecting xmlns:xlink="http://www.w3.org/1999/xlink">01</sub> from upstream end of SWS by using...

To provide high power Gaussian radiation that is attractive for many applications an X-band 460 kV relativistic BWO proposed in which a Bragg reflector with one-fold left-and right-spiral corrugations of its wall was applied waveguide on the "cathode" end interaction space. Such converts operating TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">01</sub> -mode to forward TE11-mode linear polarization extracted as microwave beam. Frequency...

The University of New Mexico (UNM) has two research thrusts in high power electromagnetics: (i) the development novel sources microwave (HPM) radiation with ever-increasing beam-to-microwave conversion efficiency frequency range from 1 GHz to over 100 GHz, and (ii) physics-based predictive models on how electronics (and software execution) are affected when they exposed fluctuating voltages (in frequencies) that stress their operation slightly beyond specification. This paper summarizes...

Microwave sources transform the kinetic energy of an electron beam into microwaves through interaction electrons with a periodic slow wave structure (SWS). A metamaterial (MTM) waveguide is proposed for use in microwave oscillator instead SWS, which have been used long time to generate high power. MTMs interesting properties such as negative refractive index, low group velocity, below cut-off propagation, among others.

Computer simulations using the electromagnetic code HFSS show that increasing amplitude of periodic corrugation slow wave structures (SWSs) leads to expanding stopbands and decreasing maximal frequency in first passband a wave. Results further decrease cut-off result appearance backward phase interval hd = (0 - π) (here d is period h wavenumber). It pertinent note this case usual interpretation passbands as bands Bragg reflection or mode conversion becomes incorrect. also incorrect interpret...

Summary form only given. The virtual cathode oscillator (vircator) can be one of the most promising high-power microwave sources due to its conceptual simplicity, high-output power capability, and potential tunability. Microwaves generated when current an intense relativistic electron beam exceeds space-charge-limiting structure. In this case, a comprising electrostatic barrier is formed. Some electrons in lose their kinetic energy are then reflected back toward anode. conversion efficiency...

Summary form only given. Metamaterials have unusual properties such as negative refractive index that provides backward wave propagation, also called Cherenkov radiation in vacuum electronics. They other unique period much less than operational wavelength, low group velocity, below cutoff among others. We are interested studying metamaterial slow structures (SWSs) a new application for high power microwave sources similar to [3]. For this reason, we developed structure comprising two...

The University of New Mexico is working on developing a multi-stream Traveling Wave Tube (TWT) amplifier [1], [2]. One the first steps to be taken during design an input coupler couple power from High Power Microwave (HPM) source slow wave structure amplifier. In order aid in development TWT which operates X-Band, multiple options for couplers have been designed use greater project at Mexico. primary tasks addressed with these designs are: converting HPM TE10 propagating mode rectangular...

Cerenkov high power microwave (HPM) sources are used to generate short pulses that attractive for national defense, acceleration, among other applications.' The backward wave oscillator (BWO), which typically radiates the <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{TM}_{0\mathrm{n}}$</tex> -mode in circular waveguide utilizing a periodic slow structure (SWS), is considered as one of most popular HPM devices due rapid risetime its...