Abstract: An intrusion detection system that provides foliage penetration is disclosed employing an array of field disturbance transceivers operating at UHF frequencies. The array of transceivers generate a multiplicity of electromagnetic wave fields between nearby units and detect the presence of intruders by detecting disturbances in these fields. The emitted UHF signals used to generate the electromagnetic wave fields are also used to provide the communication link between transceivers in the array and to a control station. The control station facilitates the operation of the array from a remote monitoring site. A unique method of array deployment provides multiple opportunities to detect an intruder and secondarily provides redundant communication links in case of a sensor failure. Automatic means of setting detection thresholds based on environmental conditions assures a high probability of detection along with a low false alarm rate.

Abstract: An intrusion detection system that is capable of foliage penetration is disclosed employing an array of field disturbance transceivers operating at UHF frequencies. The array of transceivers generate a multiplicity of RF fields between nearby units and detect the presence of intruders by detecting disturbances in these fields. The emitted UHF signals used to generate the RF fields are also used to provide a communication link between transceivers in the array and to a control station. The control station facilitates the operation of the array from a remote monitoring site. A method of array deployment provides multiple opportunities to detect an intruder and secondarily provides redundant communication links in case of a sensor failure. Automatic means of setting detection thresholds based on environmental conditions assures a high probability of detection along with a low false alarm rate.

Abstract: A surveillance system is provided for surveillance of objects within a secure area. A surveillance sensor transmits surveillance signals to all objects within the secure area, the reflections of which are received back by the surveillance sensor to determine the locations of objects, and communicates the determined locations to a pressing facility. Objects authorized to be in the secure area are equipped with an Identification Friend or Foe (IFF) unit that includes a GPS receiver and a data communication transmitter. In response to predetermined conditions, the IFF units broadcast their position and identification to the processing facility for correlation with locations defined by the reflection signals.

Abstract: A surveillance system is provided for surveillance of objects within a secure area. A surveillance sensor transmits surveillance signals to all objects within the secure area, the reflections of which are received back by the surveillance sensor to determine the locations of objects, and communicates the determined locations to a pressing facility. Objects authorized to be in the secure area are equipped with an Identification Friend or Foe (IFF) unit that includes a GPS receiver and a data communication transmitter. In response to predetermined conditions, the IFF units broadcast their position and identification to the processing facility for correlation with locations defined by the reflection signals.

Abstract: An apparatus for detection of any intruder passing through an electronic wall is disclosed. The electronic wall is formed by a millimeter-wave radar positioned at one end of the wall and a plurality of combinations of plane reflectors and retroreflectors placed along the floor of the wall as well as on structures at both ends. The wall is formed of a plurality of electromagnetic beams with each beam having two segments, one between the radar antenna and a plane reflector and the second segment between the plane reflector and a retroreflector. A sufficient number of beams inhabit the wall volume to make traversing the wall by an intruder without detection essentially impossible, even though the intruder should attempt such detection avoiding methods as crawling under or jumping over the assumed locations of the beams. The primary means of determining that an intruder is traversing the wall is the detection of one or more electromagnetic beams being partially or completely blocked.

Abstract: An apparatus for detection of any intruder passing through an electronic wall is disclosed. The electronic wall is formed by a millimeter-wave radar positioned at one end of the wall and a plurality of combinations of plane reflectors and retroreflectors placed along the floor of the wall as well as on structures at both ends. The wall is formed of a plurality of electromagnetic beams with each beam having two segments, one between the radar antenna and a plane reflector and the second segment between the plane reflector and a retroreflector. A sufficient number of beams inhabit the wall volume to make traversing the wall by an intruder without detection essentially impossible, even though the intruder should attempt such detection avoiding methods as crawling under or jumping over the assumed locations of the beams. The primary means of determining that an intruder is traversing the wall is the detection of one or more electromagnetic beams being partially or completely blocked.

Abstract: An identification interrogator is provided for surveillance of objects within an area. The identification interrogator transmits interrogation signals to all objects within the surveillance area, the reflections of which are received back by the interrogator to determine the locations of the objects, and communicates the determined locations to a processing facility to determine their authorized locations. Upon receipt of interrogation signals, some of the objects within the surveillance area broadcast their position and identification to processing facility for correlation with the locations determined by the reflection signals. The locations of other objects are found by correlating the location determined by the reflection signal with a predetermined list of objects and their location within the surveillance area. These may be objects with no means or method to transmit position and identification information, such as rock formations or buildings.

Abstract: An identification interrogator is provided for surveillance of objects within an area. The identification interrogator transmits interrogation signals to all objects within the surveillance area, the reflections of which are received back by the interrogator to determine the locations of the objects, and communicates the determined locations to a processing facility to determine their authorized locations. Upon receipt of interrogation signals, some of the objects within the surveillance area broadcast their position and identification to processing facility for correlation with the locations determined by the reflection signals. The locations of other objects are found by correlating the location determined by the reflection signal with a predetermined list of objects and their location within the surveillance area. These may be objects with no means or method to transmit position and identification information, such as rock formations or buildings.

Abstract: An apparatus for testing the operation of a CW radar is disclosed. A test antenna is placed within the field of radiation of the radar's transmit and receive antenna. The sample of millimeter wave energy collected by the test antenna is coupled to a switch that routes the sample to either a dissipative load or to a reflective short. When the sample is coupled to the load the energy is absorbed. When the test antenna is coupled to the short, the sample is reflected back to the test antenna and re-radiated. A control signal produced by a square wave generator is coupled to the switch and determines whether the sample is absorbed or reflected. The result is the re-radiation of an amplitude modulated sample of the energy transmitted by the radar to form a test signal. Means are provided to adjust the frequency of operation of the square wave generator.

Abstract: Method and apparatus for eliminating the effects of clutter in a coherent pulsed Doppler radar including determining the center frequency of the clutter and periodically moving the local oscillator frequency so that the clutter is shifted out of the Doppler filter passband, leaving only targets in the passband.

Abstract: A system and method for reducing the blind velocity problems in MTI coherent pulsed Doppler radar systems comprising an agile local oscillator which is preprogrammed to operate sequentially at more than one frequency unitl a target of interest is acquired.

Abstract: A launch envelope computation system adapted to be mounted on a missile including a radar for providing signals indicative of range, range rate, target angle and target angle rate of change, a memory for storing a maximum and minimum missile envelope, a computer connected to receive signals from the radar and additional signals from a launch vehicle including velocity and altitude, for updating the missile envelopes, and a computer connected to the memory means and the radar for determining whether a target is within the missile envelope and providing launch or no launch signals, as well as indication of what altitude changes, if any, are required in the launch vehicle to allow a launch.

Abstract: In apparatus for discriminating targets from clutter, a high threshold circuit for passing only signals with sufficient amplitude and a lower threshold circuit passing signals of a sufficient amplitude to range extent circuitry, which passes only signals within a predetermined duration and which do not have other range signals adjacent thereto, and to frequency extent circuitry, which passes only signals within a predetermined bandwidth and which do not have other frequency signals adjacent thereto. Signals which satisfy the amplitude, range and frequency requirements then provide an output indicative of a target; all other signals are rejected as clutter.

Abstract: A platform stabilization system utilizing a small free running gyro, gimballed to the platform, as the reference element. Optical means are used to generate error signals in a torque free subsystem for sensing misalignment between the reference gyro and the platform. A system of magnetic rods and surrounding electrical solenoid coils are used to initially position the reference gyro. The reference gyro to platform gimbals are located within the structure of a second gimbal system mounting the platform to a pedestal mount. The close spacing of the axes from the platform yields a minimum swept volume of the pedestal in operation. Torque motors located in the pedestal are coupled to the platform gimbal by means of flexible cables. The motors are controlled by amplified signals from the optical error sensor signals. The result of this design is an extremely compact, high speed, low mass, low cost, stabilized platform system.