The Boeing Company

Ervin J Nalos

James C Axtell

Walter W Lund, Jr

George W Fitzsimmons

Prentis B Drew

Donald E Skoumal

Disclosed is a method and apparatus for generating a very fast electron pulse (30) in a vacuum. The electron source comprises a pulse-forming line (12), a solid-state switch (14), a cold field-emitting cathode (16), and an anode grid (18). The anode grid forms a portion of a side of an evacuated circuit (20) that may be used to produce an oscillating output signal or that may be a portion of a waveguide carrying an rf signal to be amplified. In operation, the pulse-forming line is charged to a desirable voltage. The solid-state switch is then closed, coupling the pulse-forming line to the cathode. An electric field develops between the cathode and anode grid. Under the influence of the electric field, the cathode emits an electron current pulse that is attracted by the anode grid. The current pulse enters the region between the anode and closure grids, and interacts with the electromagnetic field in the cavity at the appropriate time to add its energy to the electromagnetic field of the cavity. A group of electron sources can be employed to provide rf generation or wideband amplification in a waveguide circuit through proper timing of the closure of a set of cathode-switch elements configured along the direction of propagation of a wave to be amplified. By proper selection of timing, a very flexible set of output frequencies and waveforms may be obtained. The propagating waveguide circuit may also be made resonant by shorting both ends, and configured for pulse-to-pulse frequency diversity by properly timing the cathode-switch current sources to generate alternative frequencies. The multiple-source resonant circuit can also be used to generate very high peak power pulses by using the set of cathode-switch sources repetitively to build up a high voltage across the cavity, with the output load disconnected, and then to discharge the built-up voltage into the load by closing a switch in the output circuit at the appropriate time.

Broadbend pulsed microwave generator having a plurality of optically

Pulsed-current electron beam method and apparatus for use in generating

A non-linear solid state conductor placed across a resonant aperture formed in a surface reflective of electromagnetic energy becomes conductive under the influence of a microwave field above a threshhold energy level of intensity to render the resonant aperture fully reflecting for the bandwidth of frequencies associated with the geometry of the resonant aperture.

Threshold sensitive low visibility reflecting surface

A satellite in geosynchronous orbit includes a source of signal illumination which is directed toward the earth, covering a given area thereof. An airborne vehicle, such as a missile, traveling over the area covered by the signal illumination from the satellite, includes a first antenna for receiving an incident set of signals from the satellite directly, and a second antenna for receiving the same signals from the satellite after they have been reflected from the earth's surface, referred to as a reflected set of signals. The altitude of the airborne vehicle may be ascertained by comparing the relative times at which the two sets of signals are received at the airborne vehicle, while the remaining location information, referred to as ground map information, may be ascertained by first determining range and angle data from the reflected signals and then comparing that data with ground map data stored aboard the airborne vehicle.

System for determining the location of an airborne vehicle to the earth

An electrical power distribution system wherein electromagnetic energy irradiates a large spatial area is configured to include an array of antenna-rectifier modules wherein the receive aperture of each module is established in accordance with the electromagnetic field intensity at the location of that particular module so as to provide the rectifier circuitry with a predetermined amount of electrical power. Each antenna-rectifier module includes an array of high impedance (e.g., antiresonant) dipoles that are spaced apart along a two-wire transmission line. The total number of dipoles employed is established to provide the desired receive aperture and the impedance of each dipole is established so that the total impedance of the array substantially matches that of the rectifier circuitry employed. The rectifier circuitry is enclosed in and electromagnetically shielded by a conductive housing that is removably interconnected with the array of antenna elements and first and second filtering circuits are included to respectively eliminate high frequency signal components that can be coupled to and radiated by the antenna structure and high frequency ripple within the DC output signal.

Combined antenna-rectifier arrays for power distribution systems

The waveguide is constructed with a specially designed laminate which comprises multiple plies of a graphite-epoxy composite. Thermal compensation is achieved by orienting the graphite fibers in the various plies in selected directions. Graphite fiber has a negative coefficient of thermal expansion while epoxy has a positive coefficient of thermal expansion. At least one ply in the laminate has longitudinally oriented graphite fibers while a second ply has transversely oriented fibers. Third and fourth plies, intermediate of the first and second plies, have graphite fibers which are oriented at selected angles relative to the longitudinal and transverse plies. The angles of orientation of the graphite fibers in the intermediate plies are selected by use of an equation and a set of curves relating the temperature characteristics of the laminate to fiber angle, once the width of the waveguide and the free-space wavelength of the signal propagated in the waveguide are known.

Growing community of inventors

Bellevue, WA, United States of America

Ervin J Nalos