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 dual wavelength continuous wave (cw) solid state microlaser device that provides simultaneous laser action at a first and a second wavelength. The laser comprises a solid state gain material including a rare earth element having a first gain transition at the first wavelength and a second gain transition at the second wavelength. The gain material defines a block having a first face and a second, opposite face. A first reflective surface that is substantially reflective at both the first and second wavelengths is closely coupled to the first face. An output coupler provides a second reflective surface that is partially reflective at both the first and the second wavelengths, which is oriented with respect to the first reflective face to define an optical cavity through the first and second faces of the solid state gain material. An optical pump source is provided to end pump the solid state gain material with continuous pump radiation at a pump wavelength that is highly absorptive by the gain material.

Abstract: The present invention provides a photodetector having an advantageous combination of sensitivity and speed; it has a high sensitivity while retaining high speed. In a preferred embodiment, visible light is detected, but in some embodiments, x-rays can be detected, and in other embodiments infrared can be detected. The present invention comprises a photodetector having an active layer, and a recombination layer. The active layer has a surface exposed to light to be detected, and comprises a semiconductor, having a bandgap graded so that carriers formed due to interaction of the active layer with the incident radiation tend to be swept away from the exposed surface. The graded semiconductor material in the active layer preferably comprises Al.sub.1-x Ga.sub.x As. An additional sub-layer of graded In.sub.1-y Ga.sub.y As may be included between the Al.sub.1-x Ga.sub.x As layer and the recombination layer.

Abstract: An apparatus and method is disclosed for accurate, real time monitoring of the wavefront curvature of a coherent laser beam. Knowing the curvature, it can be quickly determined whether the laser beam is collimated, or focusing (converging), or de-focusing (diverging). The apparatus includes a lateral interferometer for forming an interference pattern of the laser beam to be diagnosed. The interference pattern is imaged to a spatial light modulator (SLM), whose output is a coherent laser beam having an image of the interference pattern impressed on it. The SLM output is focused to obtain the far-field diffraction pattern. A video camera, such as CCD, monitors the far-field diffraction pattern, and provides an electrical output indicative of the shape of the far-field pattern. Specifically, the far-field pattern comprises a central lobe and side lobes, whose relative positions are indicative of the radius of curvature of the beam.

Abstract: A method and apparatus is disclosed that provides a laser output beam having a broad bandwidth and an intensity smooth over time. The bandwidth of the laser output can be varied easily by varying the intensity of a broadband source. The present invention includes an optical modulation apparatus comprising a narrowband laser that outputs a horizontally polarized beam (a "signal beam") and a broadband laser that outputs a vertically polarized beam (a "pump beam") whose intensity varies rapidly. The two beam are coupled into a birefringent laser material so that the respective polarizations coincide with the principal axes of the material. As the two beams travel through the material, the polarization preserving properties of the birefringent material maintain the respective polarizations of the two beam; however there is coupling between the two beams as a result of cross phase modulations, which induces a bandwidth change of the signal beam.