Abstract: A self-authenticating apparatus for effecting secure communication of a binary signal. In the encipherment apparatus, key is generated as a function of plain text summed with a pseudorandom linear sequence. The decipherment apparatus performs a reverse function in an autokey mode. Incoming cipher text is summed with generated key to create a plain text stream. As in the encipherment device, key is generated as a function of the resulting plain text summed with a pseudorandom linear sequence.

Abstract: A system for communicating simultaneous encrypted messages in a jamming eronment with a low opportunity for depth exploitation. The system includes a plurality of transmitters, each having a high speed key generator for producing a plurality of pseudorandom bit streams. The bit streams are combined with a unique identifier in each transmitter to produce a single unique key stream, which may be added to a binary data stream to create an encrypted message for transmission. The receiver includes a single key generator identical to those in the transmitters and a plurality of combiners and correlators to enable simultaneous recovery of each transmitted encrypted message.

Abstract: An authenticator circuit and message authentication apparatus. The circuit includes a plurality of shift register stages, some of which are separated by adders having an input from a succeeding stage. Switching circuits selectively control the second adder inputs to determine the shifting sequence of information passing through the register stages. A message authentication apparatus includes a key generator and authenticator circuit converted at the output of a transmitter. The input of a receiver includes a similar authenticator circuit and key generator, plus a counter.

Abstract: This invention describes a nonlinear comb filter device and a method for removing harmonic interference from a corrupted signal. Here, a corrupted signal is defined as a signal containing an impulsive signal and harmonic interference. The corrupted signal is delayed through a delay line. The delay line has a plurality of tapped output terminals each spaced at a delay time that is a multiple of the fundamental period of the harmonic interference. An odd number of taps is preferred for ease of sampling and ease of performing certain nonlinear functions such as a median. Each delay line tap is connected to a corresponding input to a nonlinear device. A median device is one possible embodiment of a nonlinear device. The delay line and the nonlinear device extract the harmonic interference from the corrupted signal.

Abstract: A method is disclosed for encoding signals for transmission to provide signals which simultaneously have specifiable autocorrelation properties and low predictability. To enhance the accuracy of time of arrival measurements in the presence of either noise or multipath due to skywaves in systems such as LORAN, the coding method provides for low autocorrelation function values at time offsets approximately equal to the expected delay between direct waves and skywaves. This is accomplished by constructing the codeword which is used to encode the signal, from an Nth difference constant ratio codeword, where the expected time delay is equal to N-bits. The constant ratio codewords and the transmitted codewords are both pseudo-randomly generated, resulting in a transmitted signal having very low predictability to an unintended recipient, thereby considerably reducing the effectiveness of attempts at jamming or other electronic countermeasures attacks.

Abstract: An apparatus is described which detects the presence or absence of coherent light and provides an estimate of the coherent light's wavelength. The apparatus employs a common-path "polarization interferometer" in which the two linear polarization paths act as interferometer legs. Electro-optic modulation is used to effect periodic differential path length changes in the interferometer. The apparatus performs synchronous time-integrating detection on the light emerging from the interferometer to measure coherent contributions in the presence of obscuring incoherent light.

Abstract: An apparatus for producing multiple independent binary bit streams from a single underlying key stream. The output from a high speed key generator is fed serially into a multistage shift register. At preselected intervals, the contents of the register are parallel dumped and logically combined with a stored binary word to generate a binary bit which is gated to an output. A plurality of linearly independent binary bit streams result when the register contents are combined with a plurality of linearly independent binary words, one word for each output.

Abstract: A three-mode seat for a motor vehicle cooperable with an adult seat belt assembly to provide three modes of operation including an adult seat mode, a large child booster seat mode, and a small child mode. The seat includes a child's seat module arranged to be secured to the seat back frame between the space provided between two side cushions. The module includes a rigid back panel which carries a cushion assembly and a child's seat belt assembly.

Abstract: A method and apparatus for secure, fast storage and retrieval of information relative to a storage device without interactive checking is characterized by the use of a unique variable range adder. The variable range adder automatically modifies addresses to the storage device and causes data storage and retrieval to conform to the Bell and LaPadula security model, independently of software.

Abstract: A fuser roll including a hollow cylinder having a relatively thin wall, the cylinder being a plastic composition reinforced with a conductive fiber filler, the plastic composition having a resistivity between 0.5 and 0.05 ohm.cm, the cylinder having an outside and an inside surface and enclosing ambient air, a back up roll disposed in an engaging relationship with the outside surface of the hollow cylinder defining said nip, a heating element disposed within said relatively thin wall, the heating element being said conductive fiber filler, the conductive fiber filler also providing the mechanical reinforcement of the hollow cylinder, and an additive, the additive being part of the plastic composition, the additive providing a release layer on the outside surface of the cylinder, the additive being a fluorocarbon at approximately 0.25 percent by weight.

Abstract: An outer product shearing interferometer for an optical source of one-dimensional extent which provides interference between every two points on the source. The interferometer comprises an input plane containing the source, an output plane for observing the outer product, a hologram which imparts the sum of two contributions whose phases are bilinear functions of the spatial coordinates, a two-dimensional Fourier transform system which illuminates the hologram with the transform of light from the input plane, and a one-dimensional Fourier transform system which takes light from the hologram and illuminates the output plane.

Abstract: An outer product shearing interferometer for an optical source of one-dimensional extent which provides simultaneous interference between every two points on the source. The interferometer comprises an input plane containing the source, an output plane for observing the outer product, an imaging system between the two planes, and a mask positioned in the transform plane of the imaging system and having slits arranged to effect the desired outer product. The desired outer product results from a simultaneous application of many lateral shears instead of only one at a time.

Abstract: A reprogrammable logic array is characterized by the use of a RAM fuse to selectively control the transfer of variable from input lines to intersecting output combination lines of the array. The configuration of the combiner array is programmed by writing to all of the RAM locations that are associated with the array. If a connection is to be made, a logical "1" is written to the RAM cell for that connection and if no connection is desired, a "0" is written to the RAM cell. The array which includes a novel input interface, can be quickly and easily reprogrammed simply by writing to the appropriate RAM cells. The RAM fuses may function as standard static RAM if the device does not need to function as a combiner.

Abstract: An improved asymmetric crystal topography x-ray imaging system employing a ine focus horizontal line source of x-rays and a crystal monochromator used in a compression mode. Relatively large horizontal and vertical dimensions of the monochromating crystal allow imaging of larger areas of imperfect crystals than previously possible, without adversely affecting image resolution. The high resolution two-dimensional images are a direct consequence of our method of controlling the probe beam divergences. An appreciably enhanced and useful intensity of monochromatic x-rays is obtained over that available with prior asymmetric crystal topography systems.

Abstract: An intrusion detection optical communication system modifies the original data signal to include a synchronizing periodic waveform. The receiver generates an inverted synchronizing periodic waveform signal corresponding with the transmitted signal to null the same under normal operation. When an intrusion in the optical system arises, power is extracted from the system and the nulled condition is disrupted. The disruption is detected and activates an alarm circuit when the disruption is above a threshold value.

Abstract: The reconfigurable pipelined processor includes a plurality of memory devices and arithmetic units interconnected by cross bars for transferring raw and processed data therebetween. A counter is connected with the cross bar to provide a source of addresses for the memory devices. At least one variable tick delay device is connected with each memory and arithmetic unit to variably control the input and output operations thereof to selectively delay the memory devices and arithmetic units to align the data for processing in a selected sequence.

Abstract: An improved tamper indicating seal is disclosed, characterized by the generation of a unique signature pattern which, if altered, is indicative of tampering. The seal includes a layer of transparent material which is applied to at least a portion of a secure object or container. A plurality of particles of refective material are randomly arranged within the layer in a unique orientation. When the seal is exposed to light, the particles reflect a portion of the light to produce a unique reflective pattern which corresponds with the orientation of the particles. Alteration of the particle orientation as a result of tampering alters the reflective pattern. Thus when the reflected pattern of a seal does not correspond with its original signature pattern, tampering is indicated.

Abstract: An optically controlled laser device is used to perform digital logic functions. The device comprises a single mode semiconductor laser including a waveguide for coupling light into the lasing caving at an angle at or near normal incidence with respect to the laser radiation generated by the laser. The single mode properties of the laser are achieved by index guiding. The coupled light interacts with the laser radiation in a small region of the lasing cavity creating a perturbation that quenches the laser output, whereby input of the coupled light enables the laser device to perform logic functions.

Abstract: In the hybrid encoder for video signals described the picture elements of a video picture are arranged into equally large data blocks and each newly entered data block, is compared with a data block of the previous video picture by means of a subtractor (SR). The data blocks of the previous picture are stored in a picture store (BS). In order to maintain the transmission bit rates as small as possible, the data blocks are conventionally subjected to a transformation (for example, a Fourier transformation) (F) and a subsequent quantization (Q). For the required strong bit rate reduction a rough quantization is necessary, which leads to a strong quantization noise. To eliminate the quantization noise a blockwise adaptive low-pass filtering (T,FTI) is performed in two signal paths of the hybrid encoder. The quantizer (Q) may then have a refined design or it may be omitted altogether.

Abstract: A method for achieving tapered contact sidewalls by wet etching during fabrication of a semiconductor device is characterized by the addition of a second layer of undoped oxide to a bilayer sandwich deposited over the wafer of the device. The second layer of undoped oxide reduces the etch rate at the oxide/photoresist interface thereby providing gradual taper and improved metal step coverage. The reduced etch rate extends the utility of wet etching without changing etchant bath concentration or temperature.