Abstract: A gas arrestor separates entrained gas from a liquid medium. The gas arrestor is a porous member, such as a woven mesh screen having pores of a size sufficiently small to enable liquid transport while inhibiting gas transport. Since the trapped gas has a tendency to accumulate on the porous member impeding continued liquid flow, a wick extends in an upstream direction from the porous member. When used in spacecraft to provide substantially gas-free liquid to a thruster, the gas arrestor is located between a tank of pressurized liquid propellant and a gas generator. Improved results are obtained by locating the gas arrestor between a pressure reducing liquid fluid resistor and the gas generator.

Abstract: A shock and acoustic mount for reducing transmission of forces between two relatively moveable members such as a mounted component and a supporting structure, providing a compressible fluid spring with large allowable relative movement of the mounted component and support structure. The mount comprises a casing, a piston shell with one end disposed in the casing and another end extending outside of the casing, and a piston housed in the piston shell, all relatively moveable in response to external axial forces. In one embodiment, the mount is filled with a compressible fluid, such as air, providing an air spring. The piston is sealingly bonded to the inner surface of the piston shell, the bond accommodating acoustic and vibration forces by deformation of the bond material. An annular seal between the piston shell and the casing accommodates large and shock forces.

Abstract: A rolling-element clutch assembly including a first race member, a second race member and a plurality of rolling elements. The first race member defines a first race surface having a first ratchet surface portion. The second race member defines a second race surface having a second ratchet surface portion. The first race surface and the second race surface define a raceway therebetween. A plurality of rolling elements are disposed in the raceway. The rolling elements provide rolling support between the first race member and the second race member when the first race member moves in a first direction relative to the second race member. At least one of the plurality of rolling elements engages the first and second ratchet surface portions when the first race member moves in a second direction relative to the second race member.

Abstract: A cable seal and method for sealing a cable termination is provided for sealing the passage of a cable into a cable-receiving structure. The seal includes a first plurality of o-rings disposed along a length of the cable adjacent the cable-receiving structure and a first length of heat-shrinkable tube which fits over the cable and o-rings for compressive engagement with the cable and o-rings to prevent moisture penetration between an inner surface of the first tube and the outer surface of the cable. A second plurality of o-rings is disposed over the first heat-shrinkable tube adjacent the first plurality of o-rings.

Abstract: An array module containing an array of electronic units is mounted in an installation frame. The electronic units can be mounted by rails in a hermetically sealed array housing and blind-mate connectors can connect the units to a rear plate. Blind-mate connectors also can connect the rear plate to the installation frame for external connection. A plurality of resilient mounts are fastened to the installation frame to protect the frame and storage array module from external shock. A thermal transfer mechanism transfers thermal energy between the electronic units and a region exterior to the installation frame. The electronic units can be enclosed in hermetically sealed chambers having side rails for rigidly fastened to the unit and a resilient support connecting the side rails to at least one of the covers of the hermetically sealed chamber.

Abstract: A method and system for logical multicasting on an Asynchronous Transfer Mode (“ATM”) switch. There is a logical replication of cells on the same physical port of the ATM switch. A block of consecutive CIs is used by the controller in the switch to create new cells. The CIs are used to control the flow through the switch and for updating the VPI and VCI.

Abstract: A multi-mode rolling element clutch assembly including first and second race members and a plurality of rolling elements. The first race member defines a first race surface having a ratchet surface portion. The second race member defines a second race surface. The first second race surfaces define a raceway therebetween. A plurality of rolling elements are disposed in the raceway. The ratchet surface portion has a multi-mode ratchet mechanism for providing first and second ratchet configurations. When the multi-mode ratchet mechanism is in the first ratchet configuration, the rolling elements may provide rolling support between the first and second race members when the first race member moves in a first direction relative to the second race member, and one of the rolling elements may engage the first ratchet surface portion when the first race member moves in a second direction relative to the second race member, thereby providing load transmission capability.

Abstract: There is disclosed a device and associated method for impeding the motion of a land vehicle travelling along a pathway on a terrain surface. First and second supports are positioned at first and second sides of the pathway, respectively, each capable of being actuated from a compressed condition to an extended condition. A propulsion system is effective to actuate the supports. A barrier extends between the supports at a mean first height that is effective to permit passage of a vehicle when the supports are compressed and supported by each support at a mean second height effective to impede passage of the vehicle when the supports are extended. When the supports are compressed, vehicles pass over the barrier unimpeded. When the supports are extended, the barrier impedes the motion of a vehicle travelling along the pathway. At least one deceleration cable mechanically couples the barrier to a brake system.

Abstract: Adjustable optical fiber grating dispersion compensators. The invention provides a fully tunable dispersion compensator with a wide dynamic range. Dispersion compensators according to the invention are based on uniform fiber Bragg grating technology. Individual gratings are tuned so that the gratings, which normally operate in reflection mode, operate in transmission mode with the frequency of interest falling just outside a reflection band edge. Gratings are combined to provide broadband, or multiple-wavelength dispersion. Tuning is provided via transducers coupled to the gratings. A control system can be connected to the transducers to provide a control signal so that the frequencies of the gratings can be dynamically tuned. The control system operates by measuring signals from opto-electronic detectors. The signals are used to determine a fractional spectral power transmitted through a filter. The fractional spectral power is related to the amount of dispersion present in the optical path of the network.

Abstract: Non-planar propellers or windmill blade assemblys are proposed which have tips that are curved to point in the same direction as the axis of rotation of the propeller. This non-conventional design results in a stronger, stiffer, and more efficient propeller or windmill.

Abstract: The presence of interfering continuous-wave signals are automatically detected in the demodulated output of a quadrature amplitude modulation data communications receiver. The transmitter is re-tuned in order to avoid the detected interferer. Statistical information concerning the received signal is accumulated at a receiver and is analyzed to determine whether a reduction in the received bit-error-rate is due to the presence of an interferer. If an inteferer is determined to be present within the signal transmission bandwidth, then the potentially available transmission band is spectrum analyzed to find a new portion of that band in which the signal can be transmitted free of the interferer. The results of the statistical analysis and the spectral analysis are conveyed back to the transmitter which then readjusts the transmission parameters and forwards the new parameters to the receiver.

Abstract: An ammunition storage and retrieval system for a weapon is provided. The storage and retrieval system includes a main magazine having a main carrier belt that is configured to store a plurality of munitions have a first set of handling characteristics and a handoff unit that retrieves a selected one of the plurality of munitions and transfers the selected munition to the weapon. The main magazine also includes an auxiliary magazine mount. There is further provided a set of auxiliary magazines that are selectively engageable with the auxiliary magazine mount. A first one of the auxiliary magazines is configured to store munitions having the first set of handling characteristics and a second one of the auxiliary magazines is configured to store munitions having a second set of handling characteristics.

Abstract: Disclosed is a method and apparatus for improving airborne vehicle tracking and guidance systems by reducing boresight error induced by polarization of the RF energy impinging on the vehicle radome. The radome wall is formed with a taper which gradually increases from the base near the vehicle antenna to the tip according to a disclosed formula which accounts for frequency, incidence angle, look angle, and the dielectric constant of the radome material. This taper of the radome minimizes the crossplane boresight error component magnitude which is polarization sensitive and produces a polarization insensitive inplane boresight error component. Also disclosed is a method of electronically compensating such radomes for boresight error where the radome boresight error data accumulated during testing is digitized and processed for compensating data in the vehicle electronic system to provide compensated tracking data for the vehicle guidance system.

Abstract: This disclosure describes systems and methods for processing voice data for secure transmission and secure receipt over a network, such as the Internet. The systems and methods include the processing of analog voice and digital information, including conversion of a voice signal into digital information (or of digital information into a voice signal) and transmission of digital information representing voice data over a network. The analog-to-digital conversion (and digital-to-analog conversion) includes coding and decoding digital information according to voice coding techniques and encrypting and decrypting digital information according to encryption techniques. The transmission of the digital information includes creation of a secure voice frame.

Abstract: A method and apparatus are described for adaptively predistorting a signal before it is transmitted by a transmitter in order to compensate for nonlinearities which are introduced. Statistical information regarding the received signal is accumulated at a receiver, and is preferably transmitted back to the transmitter for processing. The processing includes a constellation analysis to determine the distortion characteristics of the signal, which may include bias, gain imbalance, lock and quad angle errors, and nonlinear distortions including AM-AM and AM-PM conversion effects, with all of these phenomena occurring anywhere in the transmitter-channel-receiverchain. From analysis of the statistics of the distortions in the received signal constellation, adjustments are made in the transmitter and/or receiver parameters.

Abstract: An aircraft data management system provides a passenger seated on the aircraft with a number of entertainment and productivity enhancing options. Such options include, without limitation, video, audio, internet, airplane systems data and power. Located proximate to each seat group is an integrated seat box that includes a network interface card that identifies a requesting passenger for proper directing of the required data and/or power from devices that interface with a network controller back to the requesting passenger. Both on-aircraft and off-aircraft devices may be accessed by the system. While particularly drawn to aircraft, the data management system is also applicable to other venues have identifiable seating locations such as buses, passenger ships, hotels and auditoriums.

Abstract: An algorithm for emitter identification of a transmitting platform using spectral energy analysis, and a system utilizing said algorithm, wherein said algorithm processes audio signals from transmission data using a fast fourier transform, detecting gaps in said processed transmission data. It then extracts spectral features consisting of normalized energy per unit frequency from said gaps. The algorithm and system then proceed to execute a decision function based on said extracted characteristic features to identify the platform of said transmitter based on said features. A second algorithm, which may be executed in parallel with the first by said system, processes the same transmission data to detect transmission activity on a radio channel in the audio frequency range, and to detect the boundaries of transmitter keyclicks at the beginning and end of said transmission.

Abstract: An algorithm for emitter identification of a transmitting platform using microphone keyclick analysis, and a system utilizing said algorithm, wherein said algorithm processes audio signals to detect transmission activity on a radio channel in the audio frequency range, detects the boundaries of transmitter keyclicks at the beginning and end of said transmission; extracts keying envelopes from said detected keyclick boundaries; and analyzes said keying envelopes to extract features characteristic of said keyclicks. The algorithm and system then proceed to execute a decision function based on said extracted characteristic features to identify the platform of said transmitter based on the features of said keyclick. A second algorithm, which may be executed in parallel with the first by said system, processes said transmission data using a fast fourier transform, detecting gaps in said processed transmission data.

Abstract: A method and apparatus are described for adaptively pre-emphasizing signals transmitted over a stable but occasionally varying transmission medium such as a very-high-speed digital subscriber line (VDSL) signal, before it is transmitted by a transmitter, in order to compensate for frequency distortion that is introduced by the VDSL transmission line. At system start up, or whenever the parameters or configuration of the line are changed, the the line termination transceivers at both ends of the transmission line exchange calibration signals to measure the attenuation-versus-frequency curves of the line in both directions. Thereafter, whenever the signal transmission band is to be changed in either direction, the transmitter for that direction uses the measured attenuation curve for the line to calculate and design a set of filter coefficients for an adjustable pre-emphasis filter.

Abstract: Methods and systems for the computerized solution of the intersection of polygons where the product polygon and subtracting polygon are represented by vertices in a product polygon linked list and a subtracting polygon linked list, respectively. In one aspect, the vertices in the product polygon linked list and the vertices in the subtracting polygon linked list have a different orientation.