Abstract: Apparatus and method for allowing ground vehicle identification and communication utilizing IFF equipment consisting of a multi-channel extremely high frequency transmitter for IFF and data transmissions and a receiver for multi-frequency conversions and multi-channel reception. The apparatus and method has both an IFF mode of operation in which the vehicle is able to identify itself and a communications mode in which the vehicle transmits vehicle status information to other vehicles and a command unit. The transmitter comprises a first and second oscillator means for generating a number of frequency tones and a power combiner for combining the tones prior to transmission. A controller monitors the transmitted signal and operates the first and second oscillation means. The receiver consists of a channelizer for separating a received signal into separate frequency tones and a measuring means for determining the values of the frequency tones. A controller controls the comparison or decoding of received signals.

Abstract: There is described an information area of a system zone and a method for formatting a length of magnetic tape with a plurality of information areas containing volume format information for the entire tape volume. The information area contains an area for storing volume format parameters and an area for storing a volume format table generated from the volume format parameters.

Abstract: A method and apparatus system for cancelling a leak-through signal component generated by an interfering transmitter from a received/leak-through signal comprising a multiplier for multiplying the received/leak-through signal by a reference signal provided from the interfering transmitter. The system further includes an integrator for integrating the output of the multiplier to generate an estimate of the gain and phase of the leak-through signal component. A gain and phase adjustor, responsive to the generated gain and phase estimates, is also included for adjusting the gain and phase of the reference signal to generate a cancellation signal that is a substantially gain and phase matched estimate of the leak-through signal. The generated cancellation signal is then subtracted from the received/leak-through signal to substantially cancel the leak-through signal component.

Abstract: The present invention provides a read-write head for an optical tape recorder comprised of a synchronized scanning transmissive polygon and rotating lens wheel. The transmissive polygon is a multi-sided piece of transparent optical quality material for displacing a through transmitted collimated read or write light beam. The lens wheel comprises a unitary disk-shaped piece of optical quality material having a plurality of individual lenses precision molded or diamond point turned therein for focusing the through transmitted and displaced read or write light beam onto a recording media. The polygon is rotated to translate the displaced beam for scanning along a linear path aligned with an arcuate path followed each successive lens on the rotating lens wheel. The rotation of the polygon and lens wheel are synchronized such that each scan of the displaced beam along the linear path coincides with the movement of a lens along the arcuate path to trace out a data track on the recording media.

Abstract: A ceramic feedthrough for a package for an electronic device provides a plurality of electrical connections through an opening in the package. A method of making the feedthrough and of packaging the electronic device includes electrically conductive paths that are formed from a metal paste applied between green sheets that are joined and cofired to form a ceramic body. Vias extend from an exterior surface of the ceramic body to the paths to complete the electrical connection from outside the package to inside the package. A density of 50 paths per inch or greater may be achieved. The ceramic body may be hermetically sealed into an opening in the package and the body may have a peripheral extension to facilitate attachment of the feedthrough to the package.

Abstract: A liquid coolant heat exchange system for use in semimonocoque aircraft includes an arcuate planar heat sink fixed along a radius of curvature R, by forming members, a flexible arcuate planar spreader plate having a radius R.sub.2, such that R.sub.1 >R.sub.2, a heat exchange tube for transferring heat from the liquid coolant to the heat sink and means for attaching the spreader plate to the forming members to hold the spreader plate in contact with the heat sink.

Abstract: The total energy, wave type, orientation and rotation of an incident electromagnetic signal having an unknown polarization is identified through single channel frequency domain signal analysis of the incident electromagnetic wave power as measured by an orthogonally polarized electromagnetic sensor. A controlled switch samples between the power measurements at each orthogonal output of the sensor to generate a signal comprised of a carrier frequency component and two sideband frequency components in the frequency domain. The sampled radio frequency signal is down converted by a single channel receiver to an intermediate frequency where the carrier and one sideband frequency component are separated and coherently shifted to the same frequency. A phase detector and ratiometer measure the relative phase and amplitude differences between the separated carrier and sideband frequency components to identify the wave type, orientation and rotation of the incident electromagnetic signal.

Abstract: A coaxial-to-microstrip transition compensated to reduce the impedance discontinuity and parasitic inductance of the transition. The impedance discontinuity is reduced by decreasing the inductance due to the center conductor pin of the coaxial line and the inductance due to the bond wire connecting the center conductor pin to the microstrip line. The impedance discontinuity is also reduced by increasing the capacitance from the microstrip line to ground and from the microstrip line to the center conductor pin of the coaxial line. To reduce the inductance in the signal conduction path, a small diameter center conductor pin is used. A short length of bond wire, doubled around the center conductor is used to connect the center conductor pin to the microstrip line. Also, a thin dielectric substrate is used to minimize the length of the center conductor pin that extends beyond the base of the coaxial housing.

Abstract: An electrically conductive cable is shielded from electromagnetic interference (EMI) with a mesh of aluminum wire that has been treated with a chromate conversion coating. The coating resists corrosion of the aluminum wire and galvanic reaction of the aluminum wire with dissimilar metals, thereby reducing degradation of shield effectiveness due to oxidation and allowing aluminum wire to be used to reduce shield weight in corrosive environments. The mesh may include a less compressible wire, such as tin plated copper, to alleviate cold flow problems.

Abstract: A mass data storage unit includes a plurality of first data storage modules that form a mass information storage library, a data directory archive for maintaining a directory of the information contained on each data storage module, and data record/playback modules for receiving any selected any data storage module in the mass storage library. A plurality of interface computers are coupled to a plurality of host computers for receiving data and for generating request signals to access information stored in the mass storage library. A file directory is coupled to the interface computers and the data directory archive for receiving the request signals, locating in the data directory archive the address containing the stored information and generating a data address location output signal for the stored information.

Abstract: A method for enhancing lofargram data images utilizing a rule base. The system takes a plurality of sequentially occurring vertical frequency strips of a lofargram data image and computes an estimate for the mean and variance of each vertical frequency strip. A linear transformation utilizing a rule base is then applied to each pixel of the vertical frequency strip to improve the visual clarity of the lofargram data image.

Abstract: The detection and correction of errors in digital data transmitted by or stored in a media channel is provided by processing the data through a triple orthogonally interleaved error correction system. On the transmit/store side of the system, the data is encoded three times prior to placement in the media channel with two different interleaving steps performed between the encoding steps. The first interleave is an orthogonal row shuffling interleave that provides enhanced protection against burst errors. On the receive/play back side, the data is decoded and deinterleaved, with included errors detected and corrected to enable recovery of the original data. To enhance the error correction, a circuit is used for generating a symbol accurate error flag identifying symbols containing errors thereby allowing the error correcting decoders to focus on and correct the data.

Abstract: An optical system for scanning a light beam across an object where the light beam is double reflected by the reflection surfaces of a rotating polygonal mirror. Beam expander optics are included in the light path for the light beam following the first reflection by the polygonal mirror to magnify the beam diameter to fill the length of the reflective surface of the polygonal mirror at the second reflection. The beam expander optics further include lenses for demagnifying scan angle in the light beam following the first reflection. The lenses of the beam expander optics are formed with a Petzval curvature (third order Seidel aberration) to correct for the distortion induced in the optics image plane by the longitudinal shift in the entrance pupil position at the first reflection as the polygonal mirror rotates.

Abstract: A method for formatting a length of magnetic tape into a plurality of partition areas to enable data storage in any of these areas and for formatting on the magnetic tape a plurality of spaced system zones, by means of controlling programs of a recording device prompting a host computer system to input the number and spacing of the system zones and the length and number of the partitions to be formatted onto the magnetic tape. The programs also prompts the host computer system to select one of various options for placing a partitions on the magnetic tape.

Abstract: A system for RF communications utilizing an open architecture bus line is disclosed. The system consists of a single-board receiver exciter, a single-board modulator and a system control processor all interfaced to a standard bus line. All three units are implemented on single-board assemblies and are programmable to perform over a variety of frequency ranges, to operate at one of a variety of modulating schemes, and to utilize varying data rates.

Abstract: A waveguide able to operate at frequencies above 20 GHz is embedded in a printed wiring board. The waveguide is formed by evacuating a waveguide path through one or more dielectric layers of the board and joining the layers. After the layers are joined, the waveguide cavity is electroless copper plated by providing an electroless plating solution in the cavity. Thereafter, the cavity walls are electroplated to form seamless electrically conductive walls for the waveguide. A dielectric may also be provided in the cavity if desired. Electronic components may be formed in the waveguide by evacuating one or more layers of a printed wiring board in a similar manner, interconnected to the waveguide. In one embodiment, the components may convert the frequency of the signal carried in the waveguide so that higher frequency signals are processed within the RFI EMI protection of the layers of the wiring board.

Abstract: A clamp for seating a circuit card assembly (CCA) in a chassis, and for thereafter establishing thermal contact between the CCA and the chassis, includes a shaft and two wedges that extend substantially the length of the CCA. One wedge is affixed to the CCA and the other wedge moves laterally relative to the fixed wedge to expand the width of the two wedges and thereby urge thermal contact between the CCA and the chassis. The shaft is disposed in mating slots in the sliding faces of the two wedges and is joined to the fixed wedge to seat the CCA in the chassis by threading the shaft into the chassis, without effecting lateral expansion of the wedges. A flanged nut on the shaft may thereafter be used to effect longitudinal movement of the free-floating wedge to laterally expand the two wedges without affecting CCA seating.

Abstract: A system and method for estimating the number of emitters having wavefronts impinging on an array of m sensors may be used in the presence of correlated, unequal-level, as well as uncorrelated, equal-level noise. In the invention, the m eigenvalues of the sensor correlation matrix are evaluated to determine whether they are related to noise or to signals. Each eigenvalue, scaled by the estimated noise power level, is compared to the arithmetic mean of the preceding noise eigenvalues to determine whether the difference is enough to indicate the presence of a signal. Similarly, the successive slopes (differences between each scaled eigenvalue and its predecessor) may be compared to the arithmetic mean of the preceding slopes to make the determination. In an alternative embodiment, the eigenvalues are desensitized by increasing each by an amount not much larger than the first noise eigenvalue.

Abstract: A method of estimating both atmospheric conditions and surface temperatures of an object from either a single set of multispectral images or multiple simultaneously-acquired single-band images of the object. Estimates of atmospheric conditions are generated by determining and radiometrically correcting radiance values measured from the image of the object. Expected radiance values are then determined and compared with the measured radiance values. The best fit of the radiance values measured from the image of the object to the expected radiance values corresponds to the best estimate of the atmospheric conditions associated with the object. The present method estimates atmospheric conditions for the object regardless of the availability of atmospheric conditions associated with the image.

Abstract: A system for accurately locating a mobile cellular radio includes plural radio receivers, the position of each being precisely known, a satellite-based time source for providing the actual time of arrival of a radio signal at the plural radio receivers, and a device for removing multipath and cochannel interference from the received signals so that actual time of arrival of the radio signal may be determined accurately. The Global Positioning System (GPS) may be used to provide the time signal and to provide the precise location of the plural radio receivers. The system may be used to passively determine the location of the mobile radio and is accurate enough to use with a computer generated map system.