Abstract: A breaching device for controlled blasting of an object at short range includes a blasting element including an explosive charge contained within a housing, the blasting element being configured to blast the object from a preset distance. Connected to, and extending from, the housing is a stand-off rod having a length equal to the preset distance. A pyrotechnic lead pellet is associated with the blasting element and with the stand-off rod so as to detonate the explosive charge upon impact of the stand-off rod with the object. A tail is provided for stabilizing the device during its flight to the object. The tail is connected to the blasting element through a “safe and arm” device and a safety connector configured to reduce shock forces acting on the tail resulting from detonation of the explosive charge.

Abstract: A method is provided for the direction of arrival (DOA) tracking of at least one source, along a single azimuth axis or along both azimuth and elevation axes. The method includes the steps of selecting all the high peaks from a DOA function as potential track points, converting the potential track points into a plurality of tracks and selecting a true track from the plurality of tracks.

Abstract: Pressure control device, characterized in that it comprises, in combination with valve means having an open and a closed position and urged to said closed position by a pressure thrust, elastic means opposing the closure of said valve means by exerting thereon an elastic counterthrust opposed to said pressure thrust, said means being normally in a condition of normal strain or stress wherein it creates a first level of elastic counterthrust such as to be overcome by said pressure thrust when it exceeds a first predetermined level; and means for bringing said elastic means to at least another condition of strain or stress, wherein it creates a second level of elastic counterthrust such as to be overcome by said pressure thrust when it exceeds a second predetermined level.

Abstract: An airbag protection system for helicopters. Airbags are inflated either automatically or manually, or a combination of both, prior to the helicopter striking the ground, thus avoiding or ameliorating a crash. Proximity sensors detect a fast descent to trigger inflation of the airbags located beneath the helicopter fuselage so that they can cushion the impact with the ground. Venting of the gas from the airbags is also provided to release the gas from the airbags so as to prevent rebound of the helicopter from the ground.

Abstract: A system and method for detecting an intruder into an area to be guarded is provided. The system includes a plurality of detection units, each of the plurality of detection units having at least one infrared sensor and having a first field of view external to and directed generally along the perimeter, and located within the area to be guarded. The infrared sensor may be a passive sensor. The detection units include a camera for recording intrusion within a second field of view and a controller. The controller is responsive to output of the infrared sensor, for determining when an intruder has entered the first field of view, whereupon an operator activates the camera.

Abstract: A method for determining the initial conditions for an inertial measurement nit (IMU) of a second vehicle launched from a wing of a first vehicle is provided. The method includes the steps of defining a state vector x as including (a) the rotation .zeta. of the computed coordinate axes with respect to the real coordinate axes of the second vehicle and (b) the projection .delta..alpha. along the Z axis of the first vehicle of the rotation of the second vehicle from its nominal coordinate axes to its real coordinate axes. A measurement z is defined as the projection .delta..beta. of a rotation angle .beta., along the Z axis of the first vehicle, between the nominal coordinate axes and a current computed coordinate axes. The method also includes the steps of estimating x over time with a Kalman filter, wherein the projection .delta..beta. is the measurement vector and the state vector x changes only due to random noise and processing x to produce the attitude about the Z axis of the first vehicle.

Abstract: A frequency-shift-keyed PLL frequency synthesizer with large frequency-muplication factor, with absolute frequency deviation independent of frequency-multiplication factor. The PLL also has fractional frequency-multiplication-factor programming capability. The PLL is inexpensive to implement, and potentially capable of fast frequency changing, due to lack of need to compensate modulator frequency deviation with possible resulting stabilization-time requirements, associated with each PLL output-frequency change. The PLL frequency synthesizer preferably employs a PLL-DRO and subharmonic mixer to achieve stable, low-noise microwave output frequencies.

Abstract: A control system for controlling an airborne vehicle at a time of low aerodynamic moment is provided. The control system includes combined aerodynamic and thrust vector control actuators, a quaternion generator which determines a quaternion error value defining the error between the quaternion of the vehicle and the commanded quaternion; and a controller which controls the actuators based on the quaternion error value, an aerodynamic control gain and a thrust vector control gain.

Abstract: A method for transmitting a sequence of images is provided. The method indes the steps of previously defining that the sequence of images includes a plurality of frame segments and that each of the segments includes two types of images, update frames and intermediate frames, encoding and transmitting the sequence of images and decoding the transmitted sequence of images. When an update frame is present, the step of encoding and transmitting includes the step of compressing and transmitting the update frame. When an intermediate frame is present, the step of encoding and transmitting includes the step of generating and transmitting intermediate global motion parameters describing motion between the update frame and the intermediate frame. When the compressed update frame is received, decoding the transmitted sequence of images includes the step of decompressing the compressed update frame to produce a transmitted update frame.

Abstract: A noise detection system is provided which includes a receiving unit, a processing unit and a user interface unit connected together. The receiving unit consists of a three-dimensional acoustical array for generally simultaneously receiving a multiplicity of sound signals from different directions. The sound signals have at least one sound source of interest. The processing unit processes the sound signals and consists of a three-dimensional spatial filter for identifying the elevation and azimuth of each of the sound signals, a sound database containing a multiplicity of soundprints of sound sources of interest, apparatus for classifying the sound signals with the soundprints, and apparatus for providing the azimuth and elevation of each of the classified sound signals. The user interface unit indicates to the user the azimuths and elevations of the classified sound signals. The processing unit further consists of filtering apparatus for filtering extraneous noise signals received by the acoustical array.

Abstract: The apparatus for and method of generating a coherent signal whose amplit, frequency and phase can be accurately controlled. A first and second signal are synthesized digitally in response to separate frequency and phase input data. The second synthesized signal is heterodyned with a coherent oscillator signal. This heterodyned signal, in turn, is heterodyned with the first synthesized signal to produce a coherent signal generator output. The amplitude of the generator output signal may be varied in accordance with attenuation input data. A phase modulator provides phase shift key modulation of the output signal in accordance with a phase control signal. In addition, a switch gates the output of the final mixer under control of a switch control circuit which determines the pulse width and timing of the signal generator output.

Abstract: A method of processing an electronic signal so as to facilitate the reduction of spurious signals, which includes mixing the electronic signal with a first synthesized signal of varying frequency to form a combined signal, passing the combined signal through at least one electronic component to produce an exiting signal, and mixing the exiting signal with a second synthesized signal of varying frequency which is correlated to the first synthesized signal, to form an output signal having spurious signals which are spread.

Abstract: An adaptive polarization diversity system for radio link communication. The system includes a base station antenna for transmitting either a clockwise polarized transmission or a counterclockwise polarized transmission, the transmission including a training pilot signal. The system further includes at least one subscriber unit for receiving the transmission, the unit including a first subscriber unit antenna for receiving a clockwise polarized transmission, a second subscriber unit antenna for receiving a counter-clockwise polarized transmission, and a dual channel receiver for adaptively combining the clockwise polarized transmission with the counterclockwise polarized transmission in proportion to first and second weights, respectively, the dual channel receiver determining the first and second weights so as to substantially optimally receive the training pilot signal.

Abstract: A system for the instantaneous determination of the frequencies and angles of arrival of a plurality of simultaneously incoming signals. The system includes beam network matrix for receiving the simultaneously incoming signals, the matrix providing one or more superimposed output signal which includes phase information associated with the angles of arrival of the signals. The system uses a Fourier receiver which includes a sampler means for periodically producing a sample of the superimposed output signals and a frequency differentiator for differentiating the sample by frequency into a train of discrete waveforms. Each of the train of discrete waveforms is associated with one of the incoming signals and includes phase information associated with one of the incoming signals. The Fourier receiver further includes a mechanism for determining frequency which determines from one of the train of discrete waveforms the frequency of one of the incoming signals.

Abstract: A hand-held probe system for imaging is described which includes a hand-held probe and a detector assembly connected by a fiber optic cable. The probe includes a hand-portable housing, a detector assembly within the housing and an IR sensor placed on the cold finger of the detector assembly. The probe can include an optical system at a known distance from the sensor and a spacing tube defining the distance between the body and the optical system. The spacing tube ensures that the body whose thermal image is being read is always at, or is very close to, the object plane of the probe. The spacing tube is typically formed of a material having minimal thermal deformation which can minimize stray IR radiation.

Abstract: A magnetron includes a cathode and an anode in a vacuum chamber radially spaced from each other to define an interaction region in which a magnetic field is produced parallel to the interaction region. The anode is supplied with positive high-voltage pulses while the cathode and vacuum chamber are at a reference (ground) potential. The anode is of annular configuration located coaxially around the cathode and is formed with cavities facing the cathode, in the form of a rod, and is formed with cavities facing the cathode to define an annular interaction region between the anode and cathode.

Abstract: A mechanism for enabling an aircraft to carry and release a store featuring hanger. The hanger has a hollow portion which is formed with a circumferential inner recess. A circular spring ring with a diameter which is smaller than the diameter of the inner recess, is dimensioned to fit within the inner recess of the hanger and to fit completely within the inner recess when a sufficient outward radial force is exerted upon it. The mechanism further includes a cylinder which fits within the hollow portion of the hanger. When the portion of the spring ring engages the outer recess of the cylinder, the hanger and the cylinder, and, therefore, the store and the carrier, are securely connected to each other. A slidable plunger having wings near one of its ends is used for pushing the spring ring into the inner recess of the hanger.

Abstract: During a portion of each frame, the detector elements of a matrix detector are illuminated at the average intensity of the scene. For each detector element, the ratio of the actual average intensity of the scene to the detector element's measured value of the average intensity is used to calibrate the detector element's measured values during the rest of the frame. In a further embodiment, more accurate calibration of the detector element's measured values is provided by additionally using the slope of the detector element's calibration curve in the calibration.

Abstract: A method and system for keeping track of artillery firings of each of a ner of artillery pieces, the method including: receiving signals produced by the firings through an array of sensors, such as acoustic sensors; processing the signals to determine which of the number of artillery pieces was the source of the firing; and storing the number of firings of each of the artillery pieces. In alterative embodiments, the method further includes: processing said signals to determine the strength of each of the firings; and storing the strength of the firings of each of the artillery pieces.

Abstract: An apparatus for use, for example, as a runway radar signal reflector, for reflecting incoming radar signals, which includes a reflector for reflecting the radar signals, a chamber through which the incoming signals pass on the way to the reflector, and a mechanism for periodically creating a plasma in the chamber so as to prevent the incoming radar signals from being reflected.