Abstract: Temperature data of each picture element output from a infrared camera looking at a scene to be watched is compared with the same data of a previous frame. Temperature data which has changed from the previous frame is input to a histogram operator having a region defined by the temperature change and quantity of the picture elements. When the quantity of picture elements in the defined region exceeds a threshold level, it is recognized that a certain object having considerable temperature change and size has been detected. Thus, a signal is output to trigger an alarm system, or to sustain circulating frame memories which have recorded the previous scenes so that the scenes of visible light as well as the temperatue patterns for frames before, on, and after the trigger signal can be reproduced as visual images of a display screen.

Abstract: A method of providing secure tactical communications between a submerged submarine and an airborne platform using a pulse-modulated blue-green laser beam. During an initial acquisition mode, the airborne transceiver sends out a downlink laser beam to the ocean surface and below using a predetermined IFF code to identify the transceiver to the submarine. In the preferred embodiment the transmit optics spread the beam out into an elongated elliptically-shaped pattern to maximize coverage of the search area. When the downlink beam energy is within range of the submarine, an optical receiver on the submarine detects the beam, filters out the background light with a very narrow-band filter, and converts the light pulses to equivalent electrical pulses. A signal processor in the submarine receiver decodes the electrical pulses and verifies the IFF code to prevent the submarine from responding to a laser beam from an unfriendly source.

Abstract: A method for producing reflectors in a continuous length of optical fiber is disclosed. The present process includes the steps of preparing the ends of two or more optical fibers, placing one or more of these fibers in a vacuum system and applying a metallic or dielectric coating to the fiber ends, and then fusing the prepared, coated ends of the fibers together until the reflectivity of the region reaches a desired value.

Abstract: A method capable of displaying the message at one time by detecting a message of 12 digits when receiving the message over 15 digits in a paging receiver of a POCSAG code system. According to one aspect of the present invention, in a paging receiver system having a display for 12 digits and utilizing a POCSAG code transmitting 5 digits per message code word.

Abstract: An improved apparatus for monitoring a respiratory circuit comprises two independent pressure sensing means, a first pressure sensing component having a preset minimum pressure for creating an alarm condition in response to pressure falling below the minimum, and a second pressure sensing component having an adjustable low pressure threshold setting means and for creating an alarm condition if the patient's breathing cycle pressure fails to periodically pass through the low threshold pressure. A preferred embodiment includes visual pressure indicating means including a display of the low threshold pressure setting and a display of the patient's breathing cycle pressures.

Abstract: A communications network comprising a hierarchy of communications systems all operating within the constraints of token ring protocols and operationally defining a single shared token ring. At least one of said systems is formed by a token ring hub as disclosed and claimed in our copending application 177,764 and is connected into a system comprising the next higher hierarchal level which may be another such token ring hub or a token ring LAN system. Each said hub has means for receiving a signal which indicates that the standard token ring protocols are satisfied with respect to the direct connection of the hub of a computer having a token ring adapter card fitted, or indicative of such a computer connected to another said hub at a lower level of the hierarchy.

Abstract: A transmitter secured to the body of the confinee is provided with tamper detection means such as a conductive mounting strap, which if broken, sets a resettable electronic latch whose output determines the status of a tamper signal receivable by a remote station located within the confinement area. The latch is connected to a timer which serves to automatically reset the latch a first interval of time after it is initially set thereby eliminating the need for external reset equipment to carry out the reset operation. In order to avoid subterfuge, said first time interval is selected to be longer than any continuous interval of time the confinee is permitted to be absent from the confinement area. Information relating to the status of the tamper signal may also be relayed to a central monitoring station.

Abstract: A repeater for receiving data transmitted thereto via a first transmission medium, transmitting that data over AC power lines to a remote location and re-transmitting that data from the remote location via a second transmission medium. The data is applied to the AC power lines by frequency modulating an FM carrier and supplying that modulated carrier to the power lines by way of a bandwidth limiting circuit. At the remote location, a resonant circuit in combination with a reject circuit receives the modulated FM carrier from the AC power lines and passes only an extremely limited band of FM signals to a tuned amplifier which, in turn, supplies the band-limited FM signals to a demodulator.

Abstract: The span of an optical dispersion-limited fiber for propagating optical pulses is improved by simultaneously chirping and amplifying the stream by means of a saturated semiconductor laser amplifier. The chirp causes a compression of the pulses as they propagate through an initial portion of the fiber, whereby the span of the fiber is increased.

Abstract: The invention relates to monitoring circuitry for the real time detection of vibrations of a predetermined frequency and which are greater than a predetermined magnitude. The circuitry produces an instability signal in response to such detection. The circuitry is particularly adapted for detecting instabilities in rocket thrusters, but may find application with other machines such as expensive rotating machinery, turbines, etc. The monitoring circuitry identifies when vibration signals are present having a predetermined frequency of a multi-frequency vibration signal which has an RMS energy level greater than a predetermined magnitude. It generates an instability signal only if such a vibration signal is identified. The circuitry includes a delay circuit which responds with an alarm signal only if the instability signal continues for a predetermined time period. When used with a rocket thruster, the alarm signal may be used to cut off the thruster if such thruster is being used in flight.

Abstract: A vehicle alarm control system built into a single integrated circuit, which includes a number of inputs including M/D-, INO-, INO+, H/T-,C.S+, and INC- which monitor a plurality of sensors strategically placed around an automobile; a fail safe/override/memory circuit which prevents the alarming of the alarm should any of the inputs become defective but allows the user to temporarily disable the defective input; and instant trigger override control which allows the user to cause the sensors to instead trigger the alarm after a delay upon the opening of the door; a main power cut warning control which triggers to provide an audible warning signal should the alarm be removed; a per-entry alert control which triggers an audible warning immediately should the automobile's door handle be touched while the alarm is armed; and a headlight on warning control which causes the alarm to give an audible warning if the automobile's headlights are on after the automobile's engine is turned off.

Abstract: An electronic signal and alarm protection proximity device is disclosed which may be strapped by a band assembly to a person's appendage or a permanent part of a piece of equipment. The instant invention transmits a signature encoded RF signal distinguishable from others to be monitored by an appropriate receiving station. When the device is taken out of range of the station or the band is severed the design is such that the signal at the receiving station is no longer received and an indication is thus had that the person or the equipment to which the device is or was secured may be leaving the allowed range of proximity and thus a search or other measures may be immediately initiated.

Abstract: In a fire monitoring system for monitoring the occurrence of a fire in which a space to be monitored is imaginarily subdivided into plural subspaces so that plural channels passing through the subspaces are set so as to intersect to each other in a lattice form. The propagation speed of ultrasonic waves propagating through each of the channels is measured, on the basis of which the propagation speed of the ultrasonic waves in each of the subspaces is calculated in the same manner as the solution for each element of a matrix is obtained, and then the temperature in each of the subspaces is obtained. By providing the system with a humidity sensor, the temperature for a dry condition is obtained.

Abstract: In a polarization diversity receiver comprising demodulator circuits (31, 32) which may have a restricted dynamic range, input intermediate frequency signals are supplied from optical detectors (16, 17) to automatic gain controllers (21, 22) for producing output intermediate frequency signals with their intensities adjusted optimal to the respective demodulator circuits irrespective of a fluctuation which may appear in a polarization state of a signal beam supplied to the receiver. Supplied with the output intermediate frequency signals, the demodulator circuits deliver baseband signals to a signal combiner (43) with their intensities adjusted so as to have a ratio which is equal to a square of a ration between intensities of the input intermediate frequency signals. This makes the receiver have a reception sensitivity which is least deteriorated by polarization diversity.

Abstract: A resonant frequency characteristic tag is disclosed, which comprises an electrically insulating thin film having an electric characteristic, an electric circuit consisting of a metal foil formed on one side surface of the thin film and having a predetermined length and having opposite end portions respectively formed with a capacitor section and a terminal section, the capacitor section having a piercedly formed hole extending from the side of the metal foil to the other side surface of the thin film, the metal foil being deformed in the formation of the hole into a burr-like portion extending toward the other side surface of the thin film, and an electrode metal foil formed on the other side surface of the thin film and having a size capable of containing the hole, the electrode metal foil being laminated to the other side surface of the thin film with an electrically insulating adhesive having a dielectric characteristic such that the free end of the burr-like portion and the electrode metal foil is spaced

Abstract: An anti-theft device for attachment to an object has an alarm generator for emitting an audible alarm in response to an alarm signal and a motion sensor for initiating the alarm signal in response to movement of the anti-theft device. A retaining member engages the object to secure the anti-theft device to the object and a device responsive to movement of the retaining member initiates an alarm signal in the case of tampering.

Abstract: A multi-directionally responsive, dual-status marker for use in electronic article surveillance systems having an alternating magnetic field within an interrogation zone. The marker comprises a piece of a high permeability, low coercive force magnetic material substantially coextensive with a piece of remanently magnetizable material, in which the first piece is configured to exhibit at least two elongated responsive areas adjacent to edges of the piece perpendicular to each other, each area having a narrow width region forming a switching section and adjacent extensive regions forming flux collectors. In a preferred embodiment, the inner edges of all of the regions are defined by a narrow band of removed material, the remaining material in the center thereby being magnetically isolated from the responsive areas. The marker is desensitized by uniformly magnetizing the pace of unmagnetizable material.

Abstract: A data signal and a reference signal are multiplexed into a fiber optic communications link for transmission from a first secure location to a seond location. A replica of the reference signal is transmitted from the first location to the second location over a separate communication channel. At the second location, the angular phase difference between the reference signal and the replica thereof is continuously monitored. If the angular phase difference departs significantly from a specified value, an alarm is set as a warning that the fiber optic communications link has been compromised.

Abstract: An emergency signaling device adapted to attach to an existing flashlight is disclosed. The device provides audio, optical and radio frequency alarms when the device detects no movement for a period of time. The radio frequency alarm is coded so that a plurality of the devices may be used in conjunction with a receiver to form an emergency signaling system. The receiver decodes the signal and indicates which device has transmitted the alarm. The device uses the battery in the flashlight for power. A noxious gas detector may also be integrated into the device.

Abstract: The method and apparatus for testing a personal barrier such as a medical glove comprises establishing a reference circuit through the body of an individual wearing the personal barrier. An electrical lead is connected with a saline solution or the body of the patient. The defective personal barrier is indentified through the establishment of an external circuit through the practitioner and the test solution or the patient. An alarm is sounded to alert the wearer to the defective condition. The detection is preferably accomplished by means of sensing the resistance of the external circuits.