Abstract: A device and method of manufacture for producing electrically conductive regions in hermetically sealed insulative plates or hermetically sealed electronic component enclosures. The electrically conductive regions consist of a monolithic composite material comprising particles of an insulative material and a conductive metal. The material of the insulative particles, their size, and the type of conductive metal used are selected so that the coefficient of thermal expansion (CTE) of the resulting electrically conductive region approximates the CTE of the surrounding material.

Abstract: A circuit card assembly thermal core includes a composite material that includes particles of diamond and a conductive metal such as aluminum, copper, nickel and beryllium and which may be made by pressure infiltration casting. The diamond particles are 110 to 160 microns in size and 10 to 80 percent by volume, and preferably 140 to 160 microns in size and 40 to 60 percent by volume. The composite material has both a high thermal conductivity and low density which may be matched with the coefficient of thermal expansion of other materials with which used.

Abstract: A printed circuit board includes vibration areas where vibration sensitive components of an electrical circuit design fabricated on the printed circuit board are mechanically isolated from supporting circuitry. The present invention provides a printed circuit board with areas having an increased natural resonant frequency of vibration for the circuit board area where the vibration sensitive circuit is located. The printed circuit board comprises a number of slots, holes or other openings around the vibration sensitive circuitry. In addition, one or more circuit board conductive paths are provided for maintaining electrical conductivity between the isolated circuit and the supporting circuits.

Abstract: Separations between the end of one data file and the beginning of the next data file are recognized, without utilizing an entire data storage block by means of a controlling program for a peripheral recording device monitoring the control information headers of helically stored data on a recording tape. When files are stored on the recording tape, the controlling program increments an increase of a file section number by one and increments to zero a data block number at the beginning of a new data file. When the recording device is reading the recording tape and there is detected an incrementation of the file section number and a zero value for a data block number, a recognition is made that this data indicates the end of one data file and the beginning of another data file.

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: 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: 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: 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.