Invention: Microwave-oven gun
NewScientist.com news service 23 October 2006 Barry Fox
[
www.newscientisttech.com]
Microwave-oven gun
You can do a lot of damage with a directed beam of microwave energy. It can destroy electronics by inducing high voltages in chips and wires (just as metal objects spark if left in a microwave oven). Such a beam could also burn a person's skin, or even detonate improvised explosive devices by exciting unstable chemicals.
A megawatt magnetron is normally needed to make the beam, though, and these are big and expensive beasts that need water cooling.
However, two inventors from Albuquerque, New Mexico in the US, reckon there is cheaper way to get the power. Simply gather together a stack of magnetrons ripped out of consumer microwave ovens, and lock their output together so that they combine into one coherent beam. What is more, they say, the trick can be done mechanically.
Microwave magnetrons come with a tube-shaped component that controls the output signal. The idea is to arrange a dozen or so side by side and have a small metal plate in front that reflects some of the energy from each tube back into the mouth of adjacent ones. This should make all the magnetrons resonate in synchronisation, the inventors reckon. Three hundred consumer devices, rated at 1 kilowatt each, could combine to generate megawatt pulses from the back of a mobile generator.
The only puzzle is why the US government Patent Office has published an application that might explain to anyone, including terrorists, how to build such a weapon.
Read the full microwave oven gun patent
[Aus Sicherheitsgründen lassen wir den Link zur ausführlichen Patentschrift und Bauanleitung für diese Waffe weg! R. Munzert]
Kommentar: Der NewScientist-Bericht und die Patentschrift stellen einen weiteren Dammbruch für die Wahrheit dar. Eindrucksvoll bestätigen sie Ausführungen wie sie auf unserer Website www.mikrowellenterror.de seit Jahren vorgebracht werden. - In gewisser Hinsicht ist der Artikel Gift für Mikrowellen-Verbrecher!
Der Patentantrag stellt an mehreren Stellen dar, dass billige und legal zu erwerbende Mikrowellenerzeuger (Magnetrons), wie sie in Haushaltsmikrowellen zu finden sind, zu einer Directed Energy Weapon (Waffe mit gerichteter Energie) zusammengefügt werden können. Diese Mikrowellen-Waffe kann Mikrowellenstrahlung gezielt und wirkungsvoll auf spezielle Bereiche/Ziele, natürlich auch Menschen, übertragen:
"A directed energy weapon system for projecting microwave energy along a predetermined path, the system comprising: a plurality of magnetron tubes each having an anode coupled to an output cavity, and a primary coupling waveguide having a sidewall disposed to transfer microwave energy from the magnetron output cavity to free space to produce a radiated microwave field, wherein the magnetron tube plurality is disposed in an array having a plurality of columns and a plurality of rows..."
Die technische Ausrüstung ist robust, kompakt, relativ unkompliziert und transportabel. Die Zusammenschaltung der Magnetrons ermöglicht es, die Mikrowellenstrahlung auf verschiedene Leistungen/Strahlenstärken sowie Zielfelder einzustellen:
"The magnetron array system of this invention is a robust compact structure with far less mechanical complexity than similar arrays known in the art. The advantages of the system of this invention include reduced complexity, reduced overall system size, weight, and cost and improved reliability. FIGS. 6A-7B demonstrates that a stable phase-lock is achieved over the magnetron array without power circulators, magic T's or phase-control electronics... It is an advantage of the system of this invention that it is scalable to as many magnetrons as power can be provided for. Phase-locked magnetron arrays of hundreds of cheap commercial magnetron tubes may be embodied for mobile applications using the system of this invention."
United States Patent Application 20060208672
Achenbach; Robert Parker ; et al. September 21, 2006
High-power microwave system employing a phase-locked array of inexpensive commercial magnetrons
Die folgenden Ausführungen aus dem Patentantrag sind teilweise nur für Fachleute verständlich:
Abstract
A high-power microwave generator employing a plurality of inexpensive commercial magnetron tubes cross-coupled by means of a secondary coupling path between each magnetron output pair, whereby a portion of the output energy from a first magnetron tube is injected into a second magnetron tube and a portion of the output energy from the second magnetron tube is similarly injected into the first magnetron tube. The resulting cross-injection of microwave energies brings the respective magnetron tube pair into a phase-lock sufficiently stable to permit coherent combination of their outputs for many high-power microwave applications, such as directed energy weapon systems. The magnetron phase-locking system requires no external components other than the secondary coupling paths of this invention...
5. The system of claim 1 wherein: the plurality of magnetron tubes includes a plurality of standardized commercial magnetron tubes suitable for microwave oven applications.
6. A directed energy weapon system for projecting microwave energy along a predetermined path, the system comprising: a plurality of magnetron tubes each having an anode coupled to an output cavity, and a primary coupling waveguide having a sidewall disposed to transfer microwave energy from the magnetron output cavity to free space to produce a radiated microwave field; and secondary cross-coupling means disposed to redirect a portion of the microwave energy from a first magnetron tube output cavity into a second magnetron tube output cavity and to redirect a portion of the microwave energy from the second magnetron tube output cavity into the first magnetron tube output cavity.
11. A microwave power generator system comprising: a plurality of magnetron tubes each having an anode coupled to an output cavity, and a primary coupling waveguide having a sidewall disposed to transfer microwave energy from the magnetron output cavity to free space to produce a radiated microwave field, wherein the magnetron tube plurality is disposed in an array having a plurality of columns and a plurality of rows...
17. 22. The system of claim 17 wherein: the plurality of magnetron tubes includes a plurality of standardized commercial magnetron tubes suitable for microwave oven applications.
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates generally to high-power microwave generators and more particularly to high-power microwave systems employing a phase-locked array of inexpensive commercial magnetrons.
[0004] The conventional magnetron (herein also denominated "magnetron tube"
is a well-known and very efficient device used to convert stored electrical energy into microwave-frequency alternating currents. Magnetron operating principles have been known since at least 1921 and magnetrons have been used in extensively in microwave radars since the first pulsed resonant cavity magnetron (3 GHz) was developed by the British in 1940. Today, inexpensive mass-produced magnetrons (herein also denominated "commercial magnetrons"
can be found in every home possessing a microwave oven.
[0005] A typical single-body magnetron tube known in the art is a coaxial vacuum device consisting essentially of an external cylindrical anode (which attracts electrons) and an internal, co-axial cylindrical cathode (which emits electrons). In a typical design, the anode is grooved to form resonator cavities disposed to form a symmetric series of vanes. In operation, an electric potential ("anode voltage"
is placed across the evacuated annulus formed between the anode and cathode. Simultaneously, a constant axial magnetic field is created in the evacuated annulus that serves to cause electrons emitted by the cathode responsive to the anode voltage to travel around the cathode in paths that are `influenced` by RF fields in the anode resonant cavities. With appropriate conditions, electrons following these paths form rotating `spokes` of space charge that interact with the anode resonator fields in such a way as to induce displacement currents in each resonator cavity. As a spoke of electrons approaches an anode vane, it induces a positive charge in that vane. As the electron spoke passes, the positive charge diminishes in the first vane while another positive charge is being induced in the next vane. The physical structure of the anode forms the equivalent of a series of high-Q resonant inductive-capacitive (LC) circuits. The vanes are alternately strapped together to effectively connect the LC circuits in parallel. The induced displacement currents of each resonator are coupled to a tuned output cavity by any of various means, and from there are coupled to a primary output waveguide that conducts the microwave energy into an energy absorbing or transmitting load. The number and shape of the resonator cavities and the dimensions of the anode and cathode are most often selected by the designer based on scaled values from previous magnetron designs that are, in turn, selected for their appropriateness for the given application. Design features that might cause one type of resonator configuration to be preferable over another type include operating characteristics such as the "pushing factor," which denominates a measure of the output frequency variation arising from anode voltage fluctuations, and the "pulling factor," which denominates a measure of the output frequency variation arising from changes in RF load impedance. Clearly, as is well-known in the art, the magnetron tube is a complex resonant `system` for energy conversion whose precise operating parameters, for example frequency and efficiency, depends on many different design and load factors and may accordingly be somewhat intractable.
[SUMMARY OF THE INVENTION
[0016] This invention solves these problems by adding, for the first time, a secondary coupling path between each of a plurality of magnetron tube output pairs whereby a portion of the output energy from a first magnetron tube is injected into a second magnetron tube and a portion of the output energy from the second magnetron tube is similarly injected into the first magnetron tube. The resulting pair-wise cross-injection of microwave energies brings each respective magnetron tube pair into a phase-locked operating condition sufficiently stable to permit coherent combination of the output energies for many high-power microwave applications, such as directed energy weapon systems.
[0019] In another aspect, the invention is a directed energy weapon system for projecting microwave energy along a predetermined path employing a plurality of magnetron tubes, each having an anode coupled to an output cavity and a primary coupling waveguide disposed to transfer microwave energy from the magnetron output cavity to free space to produce a radiated microwave field.
[0042] Clearly, other embodiments and modifications of this invention may occur readily to those of ordinary skill in the art in view of these teachings.
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2 mal bearbeitet. Zuletzt am 24.10.2006 16:54 von Dr. Munzert.
