Abstract: In a method and system for deriving a seed position of a subscriber station in a wireless communications system in supporting unassisted GPS-type position determination is provided, the subscriber station receives overhead messages from the wireless communications system, and derives the seed position from the parameter values. The subscriber station may use a data structure in its memory and map possible parameter values to corresponding positions that may serve as the seed positions.

Abstract: A communication system that allows multiple data applications to work simultaneously within a distributed execution environment in which only one IP address is assigned to the mobile system by an external wireless network. The mobile system comprises a wireless communication system with a first processing device (such as a cell phone or a network card) and a second device with another processor (such as a laptop computer or a personal digital assistant). The single IP address is assigned to the second processor, and all incoming external communications are stored in the second processor. In some embodiments the first processing device includes a filter; in other embodiments the second processing device includes a proxy for each processor. Additional processors can be connected to the mobile system by adding an additional filter or additional proxy.

Abstract: A method for communication includes deploying a half-duplex terminal in a wireless full-duplex communication network configured to permit simultaneous transmission of downlink paging messages and uplink access messages between a base station and full-duplex mobile terminals in the network. The half-duplex terminal is assigned paging channel slots in a cyclical sequence of the paging channel slots, so that the base station transmits the downlink paging messages to the half-duplex terminal only during the assigned paging channel slots. The half-duplex terminal is controlled so that the half-duplex terminal transmits the uplink access messages only during an interval bounded by the assigned paging channel slots occurring in successive cycles in the sequence.

Abstract: A repeater is configured so as to detect feedback oscillation conditions by detecting a gain parameter, and responding to the detected gain parameter by reducing the gain when the loop gain approaches unity. When used in a framed shared channel wireless communication systems, feedback oscillation conditions the loop gain of the repeater may be adjusted so as to permit operation of the repeater outside of the oscillation range. The invention is particularly useful when the repeater is used in a framed shared channel wireless communication system.

Abstract: Apparatus and methods for estimating a geographical position corresponding to an event associated with operation of a wireless device communicating in a wireless communications network. The time and distance between the occurrence of the event and the related time and speed of the wireless device of at least one of a first and second geographical position, respectively measured before and after the event, are analyzed. These analyses includes comparing those metrics to predetermined time and distance thresholds to associate and/or estimate a geographic position of the wireless device with the event.

Abstract: A storm drain filter including a frame holding a filter assembly to filter incoming drainage water and thereby prevent sediment from entering the storm drain's inlet. The frame can be easily removed and replaced to allow street sweeping. In one embodiment, an erosion control apparatus comprises one or more broom filters each including a plurality of adjacent bristles, and a frame that holds the broom filter(s) so that the bristles extend downwardly to the road surface. In one embodiment, the beam of the broom filter is pivotally connected to the frame, and the bristles have substantially greater than a 90° vertical angle, to allow the weight and flexibility of the bristles to conform to variations in the road surface. A filtration bag to filter hydrocarbons may be attached downstream of the broom filter. The frame can be designed for a wide variety of implementations, and can be re-usable.

Abstract: A laser includes a narrow bandwidth AR coating for defining a frequency range for laser emission within the laser cavity. Advantageously, the narrow-band AR coating has a very low loss, which can be particularly useful if the gain medium has low gain. The narrow-band AR coating can be used to narrow the laser emission from a broadband gain medium (e.g. Cr:LiSAF), or to select from among discrete transition lines (e.g. Nd:YAG) without the use of cumbersome tuning elements. An etalon may be utilized to further narrow the fundamental wavelength, and the etalon may be substantially uncoated. For a solid state gain medium, the AR coating may be formed on one of the optical faces. A nonlinear element may be included for frequency-conversion, and the AR coating constrains the lasing frequency in the presence of this nonlinear loss and assists in maintaining single frequency operation to provide a stable frequency-converted output.

Abstract: An inexpensive, robust, and adhesive-free method and apparatus is disclosed for efficiently coupling first and second optical components together utilizing a flexure assembly for fine alignment. An initial three-dimensional rough alignment process positions the first and second optical components proximate to each other and aligns them in three dimensions. The first and second components are then misaligned by a fixed amount, causing a defocus, and then securely fastened together. The fine alignment process uses standard machine screws, or other easily attainable, robust tensioning means to progressively increase the tension around the periphery of the flexure assembly, which causes the flexure to bend and the second optical component to translate along the longitudinal axis of the flexure assembly and tilt with respect to the longitudinal axis of the flexure assembly, which re-focuses and three-dimensionally finely aligns the optical components for optimum coupling efficiency in a simple and secure manner.

Abstract: The invention relates to a centrifuge provided with a blood bag system having an upper and lower outlet for separation of blood constituents, containing a rotor which can be driven in a rotative manner about a hub, wherein at least one conventional whole blood bag equipped with an upper outlet and with a lower outlet can be positioned vertically in this blood bag, while the whole blood bag can be arranged on the rotor in such a way that one outlet of the whole blood bag is bent in a radial direction, and the opposite outlet of the whole blood bag is bent in the other radial direction, so that the entire whole blood bag and the outlets thereof adopt an approximately Z- or S-shaped form in its functional position. In this case it is preferred that the upper outlet of the whole blood bag lie radially toward the interior and the lower outlet of the whole blood bag lie radially toward the exterior of the whole blood bag.

Abstract: A shipping pallet that has a load bearing deck with a plurality of domes that provide high strength, stiffness, and rigidity to the deck, and an undercarriage for supporting the deck and for receiving a forklift, palletjack, hand truck, or other automated machinery. Each dome is defined by an apex located proximate to the upper surface of the deck and a plurality of legs extending from the apex and ending at the lower surface of the deck. The domes are arranged adjacent to each other and define an array such that a load applied to the upper surface of the deck, substantially on the apex of the domes, will cause the applied forces from the load to be transmitted substantially laterally along the legs of the arches thereby producing intersecting compressive forces between adjacent domes that enable the load bearing deck to have high strength, stiffness, and rigidity.

Abstract: A single frequency filter for a laser, comprising a polarizer that defines a direction of polarization and one or more birefringent elements situated within the cavity with their dielectric axes offset from the direction of polarization. The ends of the birefringent elements have a finite reflectance, and may be coated for reflectance or left uncoated. In some embodiments the filter is situated in a laser cavity with a broadband gain medium, in other embodiments, the filter is situated in an external cavity. To provide tunability, a wavelength control system is coupled to the birefringent element. An embodiment is described in which the filter comprises two birefringent elements of unequal optical length along the optical axis, which advantageously reduces the voltage required to tune the frequency. To provide tunability, the first and second birefringent elements are both coupled to a wavelength control system that simultaneously controls both elements.

Abstract: A multi-screen laser projection system comprises a laser source that generates a plurality of laser beams, an image display control system, a plurality of modulator arms each including a light modulator; and an optical switch coupled to the image display control system and modulators. A plurality of projection optical systems are respectively arranged to project the modulated light from each modulator onto its associated screen. The optical switch is arranged to receive the plurality of beams from the laser source and switch each of the beams to one of the modulator arms in order to illuminate each modulator with a sequence of colors during each frame. During the course of a frame, each of the colors becomes incident upon the modulator. The projection system disclosed herein can provide a cost-effective, efficient true digital projection display system with high resolution and high brightness.

Abstract: A dual mode laser projection system having a film mode and an electronic mode that can be used to project an image onto a screen. In the film mode an image is projected by illuminating film with lasers, and in the electronic mode an image is created by modulation of with lasers with data to project an electronic image. The laser source may comprise a plurality of lasers each providing a different color, such as red, green, and blue. Laser-CRTs may be used. In some embodiments the laser source is synchronized with the film aperture so that the laser source is modulated to illuminate the film aperture only while a frame of the film is stopped. In some embodiments the color temperature of the light illuminating the film can be selected by increasing and/or decreasing the relative light intensity contribution of each of the lasers.

Abstract: A low noise laser includes a birefringent gain crystal arranged so that polarization is not constant within the gain crystal. The gain crystal and an intracavity optical element each have a nonzero polarization retardance. The total single-pass retardance is approximately equal to an odd multiple of one-half wave; for example each may provide one quarter wave retardance. In one embodiment the optical element comprises a nonlinear crystal situated within the laser cavity for Type II frequency doubling. The principal crystal axis of the gain crystal is offset from the principal axis of the nonlinear crystal at an offset angle for example about 45°. In one embodiment a gain crystal and frequency-doubling crystal are coupled together to form a monolithic laser component. An alternative embodiment is described in which the optical element comprises a quarter-wave plate and the laser output includes substantially two linear polarizations at the fundamental wavelength.

Abstract: A shipping pallet offers significant advantage over the prior art, in that it is stronger, lighter, stiffer and more rigid, more economical, and ecologically sound. The pallet for shipping materials includes a deck that has a plurality of arch elements situated adjacent to each other and wherein each of the arch elements is situated such that a load applied to the deck will transmit forces through each of the arch elements and towards adjacent arch elements, such that forces from adjacent arch elements intersect each other at an intersection point. One advantage of this structural design is that the intersecting forces create a countervailing compressive stress to fully or partially offset the forces from the applied load by laterally redirecting the stress inducing forces.

Abstract: Optical transformer devices described herein provide a variety of area output patterns from a small light source (21). A light ejector (24) is described for transversely ejecting light injected by a light source, including a plurality of partially reflective interfaces (41) arranged along a central axis (28), the interfaces arranged so that light injected by the light source travels through each of the interfaces, the reflected light providing an area light output of the light reflected. The interfaces may utilize Fresnel reflectance or may comprise metallic or dielectric coatings. A variety of embodiments are described, such as a cylindrical configuration, a rectangular block configuration, or an N-sided polygonal configuration. In some embodiments a turning reflector (132) and polarization retarder (131) are provided to reverse the direction of light and rotate polarization on the side opposite the light source. In one embodiment, a stripe ejector (470) can be used to illuminate an LCD display.

Abstract: A highly efficient optical device comprises two opposing active non-spherical optical surfaces defined by a two-dimensional representation that is symmetrically extended to provide a three-dimensional device. A focal area, spaced apart from the optical surface and non-contiguous therewith, is defined by the two opposing active optical surfaces. The active optical surfaces each have a continuous second derivative, and the optical surfaces are defined by a polynomial with an order of at least about twenty. The optical device may comprise a transparent dielectric core, and the optical surfaces may be formed on the core. A receiver may be situated at the focal area to provide a concentrator. An extended light source such as an LED may be situated at the focal area, to provide a collimator. Faceted embodiments can provide a low aspect optical device. In some embodiments a diffuser may be used to transform incident radiation into a predetermined shape.

Abstract: A shovel and bag assembly for scooping animal refuse deposited by a pet animal. The shovel comprises a handle, a spaded loop including a spade with a protruding leading edge, a first and second support arm for the spade, a base, and a first and second extended corner. The spade and the two extended corners are configured to affix and tension the bag in an open configuration. The extended corners may each comprise a shoulder that assists in tensioning and holding the bag. In addition, the support arms may comprise a curved section proximate to the spade, which increase the tension along the underside of the spade and also widen the opening to facilitate pickup of animal refuse. After scooping the animal refuse into the bag, a rear pocket of the bag is inverted over a forward pocket, covering the soiled forward section and sealing the bag for disposal.

Abstract: An efficient frequency-converted solid state laser that outputs a single beam utilizing an angled reflector situated within the laser cavity. The laser comprises an optical cavity including a first reflector and a second reflector. A gain medium situated within the optical cavity is energized by a pump source to excite a laser emission at a fundamental wavelength. A nonlinear material is arranged within the optical cavity to convert the laser emission to a second wavelength. The angled reflector, which is reflective of the second wavelength and transmissive of the first wavelength, is situated within the optical cavity between the first reflector and the nonlinear material. In operation, the forward-propagating converted beam is reflected from the second reflector, and then combines with the reverse-propagating converted beam. The angled reflector reflects the combined beam so that it exits from the optical cavity at a nonzero exit angle.

Abstract: A progressive scan architecture for displaying a two-dimensional image by alternately scanning two or more laser beams, one after the other with a time delay between adjacent beams. The beams are arranged to become incident upon a polygon scanner in a row with an approximately uniform spatial separation and an approximately equal angle between adjacent beams. The polygon scanner scans horizontally and a galvanometer-driven mirror scans vertically. Adjacent lines are progressively scanned in sequence from top to bottom, which advantageously reduces or eliminates psycho-visual effects and is tolerant of non-linearities in the vertical scanner, allowing use of a low-cost galvo mirror. Typically, the beams in the row are arranged in pairs, and only one beam from each pair will be scanning at any one time.