USA as Represented by Secretary of the Navy

Johns Hopkins University

Daniel G Jablonski

Douglas A Oursler

Harvey Wayne Ko

Robert Osiander

Dexter G Smith

Albert D Krall

Dennis K Wickenden

Robert B Givens

James H Higbie

David M White

Thomas J Kistenmacher

John L Champion

Scott T Radcliffe

Margaret Ann Darrin

Richard W Watkins

An apparatus comprising processing circuitry may be configured to execute an interference simulation using a plurality of processing functions on interference data defined for each of a plurality of geographically diverse emitters interfering with one or more victim receivers via a data processing platform. The data processing platform may be defined via an interpretive language that does not use compiling. The processing functions may include determining aggregate interference data, based on the interference data, for at least a selected one of the receivers relative to corresponding ones of the emitters. The aggregate interference data may include directional information in both azimuth and elevation with respect to both the emitters and the receivers. The processing functions may further include displaying the aggregate interference data in a tabular format, and enabling a change to the interference data to be processed in real time to update the aggregate interference data.

Aggregate radio interference modeling and simulation platform

A Lorentz force-driven mechanical resonator apparatus that utilizes a high-Q resonant structure as both a mixing device and a high-Q bandpass filter. Specifically, an external time varying, but quasistatic, magnetic field is applied to the resonating device while simultaneously running a time varying electrical current through the device. The resulting Lorentz force (I&times;B) is proportional to the vector product of the electrical current in the bar (I) and the external magnetic field (B). Integrating such a resonant device with a magnetic field coil produces the functionality of an ideal radio frequency (RF) mixer coupled with a high-Q intermediate frequency (IF) filter. Wide tunability provides the capability to scan, or even step, an array of filters having very narrow bandwidths via a common local oscillator to a desired frequency range.

Lorentz force driven mechanical filter/mixer designs for RF applications

A harmonic radar nonlinear junction detector system for detecting concealed weapons, electronics, and other man-made objects utilizing state-of-the art wireless technology, circuit fabrication, signal synthesis, and computer processing techniques to detect and characterize man-made objects possessing nonlinear junctions. The system transmits a pair of low power waveforms and a receiver within the system is coherently tuned to harmonics of the transmitted frequencies of the waveforms to detect man-made metal objects and electronics that contain non-linear junctions. The receiver is also capable of receiving inter-modulation products reflected from the man-made objects that are a result of using two incident signals. The system uses two signal sources generating user-definable waveforms of variable frequencies in order to provide enhanced discrimination and target identification abilities via the processing of returned inter-modulation products.

System and method of radar detection of non-linear interfaces

A compass system and method incorporating a global positioning system (GP such as the NAVSTAR/GPS multi-satellite system, is configured to acquire accurate compass heading information without being affected by magnetic anomalies and without being dependent on the elapsed time since a previous position fix. The compass system comprises, inter alia, two antenna/preamplifiers located, for example, fore and aft a ship or aircraft separated by a predetermined distance d. A microprocessor/minicomputer portion of the system causes an electronic coaxial switch to switch a GPS receiver between the two antenna/preamplifiers automatically thereby measuring their absolute positions. The microprocessor/minicomputer computes and displays on a display unit a compass heading based on the knowledge of the absolute positions of the antenna/preamplifiers and the distance d therebetween.

Apparatus for and a method of determining compass headings

A millimeter wavelength solid dielectric waveguide having either an undulng or roughened outer surface is disclosed. As configured, and properly designed, for the wavelength of interest, the non-cylindrical surface will not have any deleterious effects on the electromagnetic properties of the dielectric waveguide. Moreover, the novel surface treatment will greatly increase the amount of heat energy that can be dissipated by radiation and convection from the dielectric waveguide thereby increasing its power handling capability.

Millimeter wavelength dielectric waveguide having increased power output

The present invention relates to a high output programmable current source. omplementary output stages are connected between appropriate power supply polarities for driving a low impedance load which is connected to circuit ground. An operational amplifier is connected between the input and emitter of each of the complementary stages providing negative feedback for virtually eliminating the input offset voltage of the respective output stage. A programmable function signal source is connected to the operational amplifiers for driving a programmable signal current to the extent possible through the load resistance from a limited voltage supply.

High output programmable signal current source for low output impedance

A plurality of passive filters in combination with a corresponding plurality of operational amplifiers form an individual series of quasi low-pass, bandpass, and quasi high-pass filters which when their outputs are summed in an operational amplifier summer, constitute a 'semi-active' notch filter having a low frequency phase shift of substantially zero, and a notch frequency which can be adjusted independently of the low frequency phase shift. The existence of the notch is also independent of the properties and limitations of the operational amplifiers used.

Growing community of inventors

Bethesda, MD, United States of America

Daniel G Jablonski