Abstract: A layer of HgCdTe (15) epitaxially grown on a crystalline support (10). A single crystal CdTe substrate (5) is first epitaxially grown to a thickness of between 1 micron and 5 microns onto the support (10). Then a HgTe source (3) is spaced from the CdTe substrated (5) a distance of between 0.1 mm and 10 mm. The substrate (5) and source (3) are heated together in a thermally insulating, reusable ampoule (17) within a growth temperature range of between 500.degree. C. and 625.degree. C. for a growth time of between 5 minutes and 13 hours. In a first growth step embodiment, the source (3) and substrate (5) are isothermal. In a second growth step embodiment, the source (3) and substrate (5) are non-isothermal. Then an optional interdiffusion step is performed, in which the source (3) and substrate (5) are cooled within a temperature range of between 400.degree. C. and 500.degree. C. for a time of between 1 hour and 16 hours.

Abstract: A method for determining whether a perceived target is acceptably close to a model target. The perceived target is first segmented using a relaxation based procedure. Structural features from the perceived target are extracted by producing a compact one-dimensional description of the perceived target's boundary. Said structural features are classified by using string-to-string matching, wherein one of two symbolic strings is a representation of the compact one-dimensional description of the boundary of the perceived target, and the other of said two symbolic strings is a pre-stored representation of the model target. The string-to-string matching entails measuring the distance between the two strings based upon deletion, insertion, and substitution of symbols from one string to the other. Performing the string-to-string matching measures how closely local structural features of the perceived target resemble local structural features of the model target.

Abstract: A generally planar antenna for generating circularly polarized electromagnetic signals, particularly useful at microwave frequencies. Each antenna element comprises a single excitation aperture (7) cut in a planar conductive ground plane (9). Spaced apart from the ground plane (9) by means of a dielectric layer (11) and covering the excitation aperture (7) is a planar conductive radiating patch (5) having slightly different dimensions along each of two orthogonal axes. The radiating patch (5) may have the shape of a near square or an ellipse. Exciting the aperture (7) with linearly polarized electromagnetic energy causes the radiating patch (5) to generate a circularly polarized electromagnetic signal consisting of two orthogonal components that have substantially the same amplitude and are 90.degree. offset in phase from each other. Several antenna elements can be combined to form a large aperture array.

Abstract: Mechanical oscillations of a mechanism containing a stepper motor, such as a solar-array powered spacecraft, are reduced and minimized by the execution of step movements in pairs of steps, the period between steps being equal to one-half of the period of torsional oscillation of the mechanism. Each pair of steps is repeated at needed intervals to maintain desired continuous movement of the portion of elements to be moved, such as the solar array of a spacecraft. In order to account for uncertainty as well as slow change in the period of torsional oscillation, a command unit may be provided for varying the interval between steps in a pair.

Abstract: A repeater for local area networks of the MIL-STD-1553B type allows extension of the LAN to remote terminals. The repeater terminates the dual LAN buses and interfaces them with a single remote bus. Normally, the repeater is transparent to all traffic in the receive direction from both buses of the LAN to the remote terminal. In response to appropriate command words from the LAN, however, the repeater automatically switches direction at the correct time to transmit traffic from the remote terminal to the active bus of the LAN as called for by the LAN protocol, and then switches back. Safeguards are provided to reinitialize the repeater if a message failure occurs or the remote terminal fails to respond to a command word.

Abstract: A telemetry data processor for processing extremely high bandwidth data such as that associated with telemetry from spacecraft. A demultiplexer (1) distributes the data onto several channels (CHl through CHn), each comprising a (preferably split-cycle synchronous) processing bus (BUSl through BUSn). Processing can occur on each of the n buses simultaneously. Several processor modules (P boards) are directly coupled to each processing bus, with each P board directly coupled to two buses. Several memory modules (M boards) are directly coupled to each processing bus, with each M board directly coupled to two buses. The functions and architectures of the P boards and M boards are described, along with those of D boards (disk controller modules) and I boards (modules for interfacing the telemetry data processor with its outside environment, which may comprise local area networks, peripherals, gateways, etc.).

Abstract: Consolidation of active and passive detectors (26, 28, 34) on a single coldfinger (20) in a dewar (10) is made possible by interposing between the detectors (26, 28, 34) an electromagnetic interference shield (64, 68) which acts as a waveguide filter blocking any interfering frequencies. The waveguide is formed by a pair of spaced interleaved shields (64, 68) one of which (64) is associated with the dewar envelope and is externally grounded, and the other of which is associated with the coldfinger (20). Photons which penetrate through the waveguide (64, 68) are deflected to the outside of the dewar (10) by a flanged narcissus shield (40) surrounding the passive detector (34).

Abstract: A control valve circuit for an automatic transmission having a variable force solenoid valve that is supplied with feed pressure by a variable force solenoid pressure relief valve to produce a signal that acts on a main regulator valve thereby avoiding high pressure forces on said variable force solenoid valve.

Abstract: A programmable voltage offset circuit (PVOC) (1) comprises a temporary latch memory (7); a latch disable circuit (5) which selects that PVOC (1) among several such circuits which may be simultaneously present on the same semiconductor chip; a resistor array (3); and a programmable nonvolatile memory (37). The desired voltage offsets V(OFFSET)s are temporarily produced in an iterative manner using the latch memory (7). Quasi-permanent voltage offsets V(OFFSET)s are then programmed using the nonvolatile memories (37), each of which typically comprises an EPROM (39). Application of an avalanche voltage V(STORE) to a PFET (43) portion of the EPROM (39) causes the PFET (43) to avalanche, thereby selectively programming the nonvolatile memory (37), depending upon the status of a signal supplied from the latch memory (7).

Abstract: The disclosed invention is a device and method for optimizing the weight and/or the heat transfer (conduction) capability of a heat transfer cylindrical sleeve. The sleeve is designed to fit around a cylindrical heat source. One particular application for this invention is where the heat source is a battery such as a metal gas battery in a satellite (where weight savings is important). Two sets of functional relationships are generated showing the relationship between the thickness of the sleeve at its top and bottom, an "area factor" (which is directly proportional to its heat transfer capability), the material thermal conductivity, and its volume per unit length (which is directly proportional to its weight). One can specify the desired heat transfer capability of the sleeve and optimize (minimize) its weight. Conversely, one can specify the desired weight for the sleeve and optimize (maximize) its heat transfer capability.

Abstract: There is provided a digitally controlled first order hold circuit and waveform synthesizer for digitally controlling the representation of a function over an approximation interval. In accordance with the operation of the invention, the first order hold circuit and waveform generator receives a digital data input signal which contains initial condition data, up/down data, and slope data for the approximation interval. The initial condition data is loaded into an up/down counter which is incremented using counting data at a rate depending on the value of the slope data and in a direction depending on the value of the up-down data. In order to minimize delays arising from data acquistion, two frequency synthesizer circuits are provided such that one frequency synthesizer provides counting data while the other frequency synthesizer receives slope data. During alternating intervals, the other frequency synthesizer circuit provides counting data while the other circuit receives slope data.

Abstract: A variable assist power steering gear mechanism for vehicles having primary and secondary steering valve portions, the primary portion controlling pressure in a power steering fluid motor, a steering pressure valve that controls the magnitude of the steering pressure as a function of vehicle speed, a steering torque sensor flow control valve that cooperates with the secondary steering valve portion to develop a steering torque signal, and an electronic signal processor for controlling the steering pressure valve in response to changes in the vehicle speed and the steering torque signal.

Abstract: A compound planetary gear system for an automotive vehicle comprising a pair of planetary gear units with a common sun gear and a driven shaft disposed concentrically within the sun gear whereby an annular lubrication oil flow passage is formed in the sun gear, the sun gear being supported by its meshing engagement with multiple planet pinions journalled in a carrier, and a flow directing funnel registering with the oil flow passage which is adapted to direct lubrication fluid into the sun gear, when it is distributed to desired lubrication points.

Abstract: A valve assembly for a swashplate air conditioning compressor comprising a valve plate, discharge valve reeds on one side of the plate and inlet valve reed on the other side of the valve plate, a seal plate located adjacent the outlet valve reeds for sealing high pressure regions from low pressure regions, and retainers securing the valve plate, the valve reeds and the seal plate together in a subassembly, one subassembly being substantially interchangeable with a second subassembly at the opposite axial end of the compressor.

Abstract: An electronic control valve system for an automatic, multiple-speed motor vehicle transmission having a torque converter with a lockup clutch and change-speed gearing adapted for four forward ratios and one reverse ratio, a converter lockup clutch control valve in conjunction with a lockup clutch shift valve adapted to control the lockup clutch, and electronic microprocessor control means for establishing ratio changes between the fourth ratio and the third ratio in accordance with separate upshift schedules and separate downshift schedules stored in the memory registers of the microprocessor, the separate registers being addressed in accordance with whether the lockup clutch is applied or released.

Abstract: The present invention is a demodulator for demodulating an unsymmetrical QPSK signal (1), i.e., one in which the amplitudes of the I and Q channels are different, and the I and Q channels have been modulated by signals having differnt bit rates. Analog versions of the I and Q modulating baseband signals are first extracted from the carrier. Each baseband signal is then subjected to a bit-rate-matched low pass filter (23, 13). The channel having the higher bit rate is subjected to a delay (32) to time-align the two baseband signals. The time-aligned filtered signals are then amplified by amplifiers (22, 12) having unequal gains that are preselected to substantially equalize the amplifier (22, 12) outputs. The amplified time-aligned filtered signals are then subjected to a phase error (E) generating means (15, 25, 16, 26, 34). The phase error (E) is passed through a loop integrator (38) and a VCO (30) and back to the baseband signal extracting means to complete a phase lock loop.

Abstract: Coolant gas pumped into the inner flask (3) of a cryostat dewar (2) causes an unwanted electrostatic charge on the inner surface (34) of the inner flask (3). This electrostatic charge can put an unwanted noise into the electrical output from an electromagnetic detector (16) cooled by the cryostat (2). The invention comprises a foraminous metallic screen (7) interposed between coolant coils (5) of the cryostat (2) and said inner surface (34). The screen (7) siphons off unwanted electrostatic charge from said surface (34) while allowing coolant to contact said surface (34) and thus allow cooling of the detector (16).

Abstract: A multiple friction plate clutch assembly having at least one intermediate plate and a pressure plate arranged adjacent a flywheel for an internal combustion engine, a diaphragm spring actuator or lever for adjusting the pressure plate into and out of a clutch engaging position, and an index element carried by the intermediate plate which engages the diaphgram spring at a point intermediate the fulcrum point of the spring and the pressure point where the diaphragm spring or lever applies pressure to the pressure plate.

Abstract: A hot gas control system includes a pressure vessel defining a chamber in which is disposed a body of solid propellant material that has a leading portion and a trailing portion. A first layer of the body of solid propellant material extends between the leading portion and an intermediate region of the body of solid propellant material, and a second layer extends between the intermediate region and the trailing portion of the body of solid propellant material. The first layer is composed of a first propellant composition that produces a relatively clean gas, and the second layer is composed of a second propellant composition that produces a relatively less clean gas.

Abstract: A vibration type sensor can make a noncontacting measurement of position or pick up the passage of an object past a point. The sensor has a coil of wire placed on a vibrating structure. As an object with an attached magnet approaches the coil, an emf is induced in the coil indicating position. Alternatively, the magnet remains fixed with respect to the vibrating coil while a material of high magnetic permeability approaches the coil and magnet combination thereby perturbing the magnetic field and changing the induced emf. This method can be used to obtain a linear variation of sensor output with position or to enable the use of the device as a pickup sensor.