Improvement to Load-pull Technique for Design of Large
... A microwave amplifier design is generally a complex and difficult task. Manufacturer of the microwave transistor usually provides a large-signal model that a microwave engineer can work with and use it to design a device working under a large-signal conditions. Unfortunately in many cases accuracy o ...
... A microwave amplifier design is generally a complex and difficult task. Manufacturer of the microwave transistor usually provides a large-signal model that a microwave engineer can work with and use it to design a device working under a large-signal conditions. Unfortunately in many cases accuracy o ...
- Pcpolytechnic
... The images you see on your monitor are made of tiny dots called pixels. The term resolution refers to the sharpness and clarity of an image. A monitor resolution is determined by the number of pixels on the screen. It is expressed as a Matrix. The more pixels a monitor displays, higher will be its r ...
... The images you see on your monitor are made of tiny dots called pixels. The term resolution refers to the sharpness and clarity of an image. A monitor resolution is determined by the number of pixels on the screen. It is expressed as a Matrix. The more pixels a monitor displays, higher will be its r ...
Electron-optical Column
... • Field emission – a single crystal (W coated with ZrO, with ZrO2 reservoir nearby), shaped to a very sharp point, and a high voltage potential is placed between it and nearby anode. Two types: cold and hot. Because of the electric field, electrons can jump the energy barrier to the nearby anode. Re ...
... • Field emission – a single crystal (W coated with ZrO, with ZrO2 reservoir nearby), shaped to a very sharp point, and a high voltage potential is placed between it and nearby anode. Two types: cold and hot. Because of the electric field, electrons can jump the energy barrier to the nearby anode. Re ...
Electrical Breakdown Of Small Gaps In Vacuum
... where ,p is the value of P when the second electrode is located at a very large distance from the first one in comparison to H , and d is the interelectrode gap. However, for values of d close to that of H , the factor P increases rapidly. Boyle et al. [3] have shown that the electrical breakdown of ...
... where ,p is the value of P when the second electrode is located at a very large distance from the first one in comparison to H , and d is the interelectrode gap. However, for values of d close to that of H , the factor P increases rapidly. Boyle et al. [3] have shown that the electrical breakdown of ...
Modeling of microdischarge devices: Pyramidal
... of the mesh was held constant at 300 K. As convective heat transfer is being ignored, this approach provides the maximum dynamic range in gas temperature and so can be considered a worst-case-analysis for the consequences of gas heating on device performance. As we are only concerned with steady sta ...
... of the mesh was held constant at 300 K. As convective heat transfer is being ignored, this approach provides the maximum dynamic range in gas temperature and so can be considered a worst-case-analysis for the consequences of gas heating on device performance. As we are only concerned with steady sta ...
- University of Surrey
... The Halo thruster was originally conceived as a permanent magnet design. It features a cusped magnetic field similar to that of the CHT, but with the novel addition of a toroidal cusp layer close to the thruster anode, produced by two concentric permanent magnets. This resulted in a large number of ...
... The Halo thruster was originally conceived as a permanent magnet design. It features a cusped magnetic field similar to that of the CHT, but with the novel addition of a toroidal cusp layer close to the thruster anode, produced by two concentric permanent magnets. This resulted in a large number of ...
Cavity magnetron
The cavity magnetron is a high-powered vacuum tube that generates microwaves using the interaction of a stream of electrons with a magnetic field while moving past a series of open metal cavities (cavity resonators). Bunches of electrons passing by the openings to the cavities excite radio wave oscillations in the cavity, much as a guitar's strings excite sound in its sound box. The frequency of the microwaves produced, the resonant frequency, is determined by the cavities' physical dimensions. Unlike other microwave tubes, such as the klystron and traveling-wave tube (TWT), the magnetron cannot function as an amplifier, increasing the power of an applied microwave signal, it serves solely as an oscillator, generating a microwave signal from direct current power supplied to the tube.The first form of magnetron tube, the split-anode magnetron, was invented by Albert Hull in 1920, but it wasn't capable of high frequencies and was little used. Similar devices were experimented with by many teams through the 1920s and 30s. On November 27, 1935, Hans Erich Hollmann applied for a patent for the first multiple cavities magnetron, which he received on July 12, 1938, but the more stable klystron was preferred for most German radars during World War II. The cavity magnetron tube was later improved by John Randall and Harry Boot in 1940 at the University of Birmingham, England. The high power of pulses from their device made centimeter-band radar practical for the Allies of World War II, with shorter wavelength radars allowing detection of smaller objects from smaller antennas. The compact cavity magnetron tube drastically reduced the size of radar sets so that they could be installed in anti-submarine aircraft and escort ships.In the post-war era the magnetron became less widely used in the radar role. This was because the magnetron's output changes from pulse to pulse, both in frequency and phase. This makes the signal unsuitable for pulse-to-pulse comparisons, which is widely used for detecting and removing ""clutter"" from the radar display. The magnetron remains in use in some radars, but has become much more common as a low-cost microwave source for microwave ovens. In this form, approximately one billion magnetrons are in use today.