Abstract: A method and device for testing transient protection circuits comprising itive and negative high voltage protection circuits and high voltage fast rise time protection circuits. A bipolar test signal with alternate positive and negative high voltage pulses is applied to the circuit under test. Determination is made whether the pulses are within a predetermined voltage window. Signals indicating pass/fail responsive to that determination are generated. A high voltage fast rise time negative pulse is applied to the circuit under test. Changes in the voltage-time waveform are sensed and compared to predetermined levels. Pass/fail signals are generated in response to the comparison.

Abstract: Measurement of the area and shape of contact between a vehicle's wheels or racks and the surface over which it moves is automated by having the vehicle drive over an array of switches connected in a matrix including X and Y conductors. The matrix is systematically scanned to produce a pulse train with one pulse therein for each closed switch, with the locations of said pulses indicating the shape of the area of contact. Circuit means are provided to count the number of pulses to indicate the area of contact and to operate a small scale display which indicates the shape of the area of contact.

Abstract: A dewpoint sensor has an inlet connected to a gas flow switch that first its air at 100 percent saturation at ambient temperature for determining a reference dewpoint temperature. The switch then connects the sensor to ambient air for determining the ambient dewpoint temperature. Entry of this temperature data in standard tables establishes relative humidity with improved accuracy at high humidity due to the measurement of both temperatures on the same sensor instrument.

Abstract: A lighter-than-air (LTA) wind energy conversion system (WECS) wherein the LTA envelope carries a main rotor and electrical generator to take advantage of high wind speeds available at high altitudes. The LTA envelope is adapted to rotate with the main rotor and is tethered to a ground based mooring system designed to provide self-orientation for the LTA envelope. In a preferred embodiment, a hollow bladed main rotor is provided at the midpoint of the rotating envelope. The rotor drives an induction turbine positioned within a substantially linear duct which is, in turn, preferably located along the longitudinal axis of the rotating LTA envelope. The output of the induction turbine is coupled to an electrical generator. In another embodiment, small wind-driven generators are positioned on the tips of the blades of the main rotor. The outputs of both embodiments are transmitted to the ground via the tethering system.

Abstract: A laser power meter is disclosed which includes a housing, an optical win in the housing through which the laser radiation is transmitted, and an optic in the housing in the path of the laser radiation. The optic absorbs a portion of the incident laser radiation, the absorbed laser radiation being converted into heat, and reflects a portion of the incident laser radiation. The heat generated at the optic is transferred to a cooling fluid flowing through a flow channel adjacent the optic. The width of the flow channel is defined by the space between the optic and a gap control disk. Apparatus is provided for urging the gap control disk toward the optic in order to maintain the width of the flow channel in the event the width of the flow channel changes as a result of thermal distortions suffered by the optic.

Abstract: A method and apparatus for a passive station to locate itself relative to a tationary or moving transmitting station transmitting a narrow pulsed scanning beam by utilizing reception of pulses directly from the transmitting station and reception of reflected pulses from a set of scatterers. A method and means for determining a bearing from the transmitting station and a method and means for determining a range to the transmitting station is disclosed utilizing a set of differential times, the times for a pulse from the transmitting station to travel to each scatterer and then to the passive station, a set of angles lying between a line connecting the transmitting station and passive station and a set of lines connecting the transmitting station and the set of scatterers and a set of angles lying between a link connecting the passive station and the transmitting station and the set of lines connecting the passive station and the set of scatterers.

Abstract: The apparatus disclosed herein is an externally adjustable flow splitter a fluid amplifier. The flow splitter is a substantial triangular plate fixedly attached to a rod rotatably mounted in the amplifier immediately adjacent to the fluid outputs to redirect fluid flow through to the fluid outputs of a fluid amplifier to null the amplifier. The rod extends externally of the amplifier and is threaded to receive externally a lock nut which can be threaded down on the rod to secure the position of said triangular plate.

Abstract: A reusable solid state device is disclosed which monitors ionizing radiat. The device is a silicon-on-sapphire n-channel MOS transistor having a back-channel leakage current which is proportional to total radiation dose. To return the monitor to its original reusable state, the drain-to-source transistor bias is reduced to zero while irradiating the device to an appropriate dose level.

Abstract: A method and device for processing spread-spectrum and other wideband comications and radar signals to obtain three and four product correlated signals. A laser beam is split and shaped into first and second sheet beams. The first beam is directed to a first acousto-optic medium where it is doubly diffracted by first and second signals. The second beam is directed to a second acousto-optic medium which is spatially rotated 90.degree. relative to the first acousto-optic medium where the second sheet beam is either singly diffracted by a third signal or doubly diffracted by a third signal and a fourth signal. The diffracted sheet beams are shaped into square beams, combined and directed to a photodiode area array.

Abstract: Near real time remote sensing of atmospheric gases is performed using differential absorption lidar or transmission techniques. The wedge absorption remote sensor (WARS) utilizes an emission spike train of short time duration as is found in the long pulse output mode of a solid-state laser to define the on and off line absorption of an atmospheric gas and hence its concentration. The laser beam is split into a reference beam and a transmission beam which passes through the atmosphere being tested. The two beams are detected and amplified, and them digitized. Comparing the ratio of the digitized reference signal to transmitted signal for each spike in the spike train yields a set of transmittance values as a function of wavelength. When the digitized reference and transmitted signals are plotted, a wedge of data points results. The ratio of the upper and lower slopes of the wedge yields the absorption coefficient and concentration of the absorbing gas.

Abstract: An acousto-optic time integrating two-dimensional frequency scanning correlator for cross-correlating signals which are separated in frequency. Two coherent light beams which are derived from the same laser are fed across respective Bragg cells, one cell having the signal A(t) cos .omega..sub.A t propagating thereacross and the other cell having the signal B(t) cos .omega..sub.B t propagating thereacross. The respective output beams are comprised in the x direction and expanded in the y direction and are made incident on an acousto-optical correlator device having chirp signals counter-propagating thereacross. The optical output is fed to a time-integrating photodiode array which provides an output signal corresponding to the cross-correlation of A(t) and B(t). In a further embodiment, the two Bragg cells are replaced by a single Bragg cell and beams having different polarizations are fed thereacross.

Abstract: A high capacity fluidic valve is disclosed which is useful for creating psure pulses in a drill string for communicating diagnostic information from the bottom of a well bore to the surface during drilling. The device of the present invention comprises essentially a vortex chamber having an element therein which is capable of rapidly changing the flow through the chamber from radial to vortical. Flow throttling action in the valve is produced by the vortical flow in the chamber, thereby producing pressure pulses in the fluid stream flowing through the valve.

Abstract: A method and device for determining the impedance of the electric and magic fields in the near and far fields associated with a radiating antenna. The electric and magnetic field components are sensed in a far field location and the system is calibrated using a known relationship between the electric and magnetic field components. The sensed signals are transmitted optically via a fiber optic link to an optical receiver. The received optical signals are modulated by an audio signal generator and input into a ratio detector via variable attenuators which are used to calibrate the system. Multiple subsequent ratios are measured and recorded as a function of location of the sensor.

Abstract: An apparatus for automatically detecting the existence of an unknown narrband signal in the presence of wide-band noise-like interference. The apparatus performs a one-bit autocorrelation at a delay time such that wide-band signals are decorrelated while narrow-band signals remain correlated. Additionally, the autocorrelation is separated into quadrature components which are re-combined to give an estimate of the envelope of the autocorrelation of the input signal.

Abstract: This invention comprises sn inexpensive, flush-mounted microstrip antenna e polarization of which is easily changed from vertical linear to horizontal linear, left-circular, right-circular or any desired elliptical sense. This enables the designer to select the polarization by selecting the proper location of shorting posts in the antenna. The use of rf switching diodes in place of conventional shorting posts provides a means of electronically switching the polarization.

Abstract: A weapon fire control system is operated to measure line-of-sight angular te and estimate velocity and acceleration of a maneuvering target. The apparent area of the maneuvering target is continuously monitored and when it becomes a value that is some preselected amount greater than the maneuvering target's head-on area, the gun line offset servos of the weapon are commanded to develop an offset which is a function of target velocity and acceleration. When the line-of-sight angular rate crosses through zero, a firing command is initiated. For a class of maneuvering targets where the product of target velocity and projectile time of flight is much less than the engagement range, performance of the weapon fire control system will be improved and power requirements of the gun line offset servo will be reduced.

Abstract: A monitor/control system for a communications network with an independent microprocessor at each repeater station and at the terminal, and in which alarms and monitored conditions are detected on an interrupt basis.

Abstract: A method and apparatus for simulating, in conjunction with a source of ionizing radiation, intense pulsed electromagnetic fields and time varying conductivity caused by the gamma radiation associated with a nuclear detonation. An enclosed space, including the source of ionizing radiation is separated into three spaces, each space separated from the adjacent space by a gas impermeable, radiation permeable barrier. A guided wave structure, pulsed with high voltage pulses in conjunction with the firing of the source of ionization radiation is disposed adjacent to the barrier separating two of the spaces. A gas handling system is provided to introduce a selected non-ionizing gas and a selected ionizing gas into the spaces on either side of the barrier adjacent to the guided wave structure.

Abstract: An electro-hydraulic (EH) actuator for converting electrical inputs into hydraulic output signals is described. The actuator features a pressure balanced design which permits operation at high absolute pressures without performance degradation. Internal portions of the EH actuator are filled with a non-conducting fluid, while a flexible diaphragm provides a movable interface between the fluid and the environment in order to equalize the internal and external pressures on the actuator.

Abstract: A method and apparatus for eliminating the sidelobe ambiguity in the range esponse of an FM-CW radar. An FM-CW signal with a periodic modulation frequency is transmitted and reflected from a target, received and combined with a sample of the transmitted signal to provide a combination signal. A portion of this combination signal including a selected harmonic and next adjacent harmonic is amplified and mixed with reference signals comprising the selected harmonic and next adjacent harmonic to provide two separate difference signals. These signals are in turn low pass filtered and further mixed to provide a range response with a mainlobe of one polarity and all side lobes of an opposite polarity. The energy under the mainlobe is detected and integrated to provide a voltage signal. When this voltage signal reaches a preset threshold level a further signal is generated.