Abstract: A wireless transmitter and receiver are used in a wireless telecommunication system and method including antennas having at least one antenna element with a relatively narrow beamwidth at both the transmitter and receiver for high data rate communication. The antenna element provides beam coverage in both azimuthal and elevational directions, and a processor is operatively connected to the antenna and is capable of determining a suitable communication path with respect to the at least one antenna element and predetermined communications conditions.

Abstract: A line interface circuit (LIC) used in telecommunications networks operates in either a high frequency mode or a low frequency mode, depending upon the status of its associated customer premises equipment. A LIC main controller detects a change in state of customer premises equipment via a battery feed circuit. If the customer premises equipment is off-hook, a switch associated with a resistor-capacitor (RC) circuit is activated to lower the resistance value of the RC circuit, and thereby, increase the operating frequency of the LIC. During on-hook intervals, the main controller deactivates the switch, and the LIC operates at a lower, default frequency.

Abstract: A hinge assembly which has a limited number of stable positions and in which the hinge automatically moves to the closest of such stable positions is disclosed. The movement of the hinge is accomplished in one illustrative embodiment by positioning the protrusion on one of a pair of ramps inclined opposite to one another and toward the adjacent recess so that the parts of the hinge rotate relative to one another, moving the protrusion into the adjacent recess. The protrusion is pressed against the ramps and the grooves by a connecting portion that joins the arm portions and is flexed when the hinge parts are assembled so as to bias the arm portions toward one another.

Abstract: A digital audio broadcasting system includes an RF transmitter and a corresponding RF receiver. In the RF transmitter, a digitally compressed audio signal is encoded into a symbol stream that is first rotated using a frequency of 150,000 hertz (hz) before transmission to the RF receiver.

Abstract: A rail-to-rail voltage-to-current converter converts a variable differential voltage signal having first and second voltage signal components, to an output current signal. The converter includes a first voltage-to-current converter configured to receive a voltage signal component and a reference voltage signal to provide a substantially linear output current signal. A second voltage-to-current converter receives the other one of the voltage signal components and the reference voltage signal to provide a second substantially linear output current signal. An adder combines the first and second output current signals to provide a substantially linear voltage/current characteristic over a wide range of available voltage signals generated by a power supply.

Abstract: The gain-bandwidth product for an integrated circuit is stabilized by operating a first capacitance element that tracks a load capacitance of an integrated circuit to be stabilized over a given range of ambient operating conditions, and operating a first control element having a control terminal and first and second controlled terminals in a triode operating region. The conductance of the first control element is set to correspond to an effective conductance of the first capacitance element by developing a feedback control voltage and coupling the control voltage to the control terminal of the first control element. The control voltage is also coupled to a control terminal of a second control element, and a controlled terminal current of the second control element is coupled to the integrated circuit to be stabilized while operating the second control element in a saturation region.

Abstract: An optical probe microscope includes an optical fiber oriented in a vertical direction. The fiber has a tip that emits light onto a horizontal surface of a sample to be measured. This surface can have both desired and undesired departures from planarity. An electromechanical device for imparting dither motion to the fiber tip is superposed on another electromechanical device for imparting two-dimensional horizontal scanning motion to the fiber tip. The dither motion has a much higher frequency than that of the scanning motion. Between successive scannings, another device moves the sample itself from one horizontal position to another. A microscope receives the optical radiation either transmitted or reflected by the sample surface. The microscope forms a (magnified) image of this received optical radiation on the surface of an optical image position detector. The surface of this detector has a relatively large area compared with that of the (magnified) image.

Abstract: Applicants have discovered methods for making, treating and using diamonds which substantially enhance their capability for low voltage emission. Specifically, applicants have discovered that defect-rich diamonds--diamonds grown or treated to increase the concentration of defects--have enhanced properties of low voltage emission. Defect-rich diamonds are characterized in Raman spectroscopy by a diamond peak at 1332 cm.sup.-1 broadened by a full width at half maximum .DELTA.K in the range 5-15 cm.sup.-1 (and preferably 7-11 cm.sup.-1). Such defect-rich diamonds can emit electron current densities of 0.1 mA/mm.sup.2 or more at a low applied field of 25 V/.mu.m or less. Particularly advantageous structures use such diamonds in an array of islands or particles each less than 10 .mu.m in diameter at fields of 15 V/.mu.m or less.

Abstract: In accordance with the invention, a tunable fiber grating comprises a fiber grating secured to a magnetostrictive body so that magnetostrictive strain will be transmitted to the grating. An electromagnet is disposed adjacent the magnetostrictive body for applying a magnetic field along the body. Control of the current applied to the electromagnet permits control of the strain transmitted to the fiber grating, and thus control of the grating spacing and reflection frequency. In a preferred embodiment the magnetostrictive body is cylinder bonded along the grating. In alternative arrangements, the magnetostrictive effect can be mechanically amplified. An add/drop multiplexer employing the tunable gratings is described.

Abstract: A linear actuator is used to push a spring-loaded ram. The loading force of the spring against a stationary workpiece is calibrated with the displacement of the ram once the load exceeds the spring preset value. At a preset loading position, an electrical contact opens, indicating that the spring load has reached or exceeded the preset value. A mechanical stop, acting in conjunction with the stall characteristics of the linear actuator, prevents the operating range from being exceeded. This device has applications where precise standoff from a surface, the application of a precise force to that surface, and a controlled rate of the application of the force is needed.

Abstract: A high efficiency resonant impedance transforming network for driving a high efficiency infrared LED and the associated method for decreasing the rise time and fall time of the LED to enable the LED to operate at higher frequencies than would ordinarily be possible. The resonant impedance transforming network includes an inductively coupled circuit that contains a primary winding and a secondary winding. The LED and at least one capacitor are coupled in parallel to the secondary winding of the transformer. The secondary winding charges the capacitors connected to it. During the rise time of the LED, the charge stored in the capacitors is discharged to the LED. The discharged charge supplements the current supplied by the secondary winding and the LED experiences a current spike during its rise time that significantly shortens the duration of the rise time. As the LED is conducting a space charge is contained within the LED.

Abstract: An apparatus and method for presenting a viewer with an overall representation of the present number of entertainment programs available for selection given one week of program schedule data for 300 or more channels and one or more filtering criteria to limit the number of items represented in the overall representation. Sequentially applied filters will filter the group of program schedule data items that has at least 100,000 half hour time slots offered by 300 channels each week into a smaller subgroup where individual consideration of each item of the subgroup can be made in a reasonable time. A set top box drives the display of overall representations or results of filtering criteria on a commercial TV set. Once a reasonable sized subgroup is obtained, other displays provide specific information of the program offerings of the subgroup.

Abstract: Apparatus and methods for editing message sequence charts and determining whether a message sequence chart is consistent with a semantic of the system which the message sequence chart represents. As an editor, the apparatus maintains an internal representation of the message sequence chart as a set of processes and events, displays an image of the message sequence chart, and modifies the internal representation in response to modifications of the image by the user. The internal representation can be used to produce further representations of the message sequence chart. One of the representations is an event list which lists send events and receive events in the message sequence chart in a visual order. The event list is used together with a semantic provided by the user of the apparatus to determine whether there is an inconsistency between the message sequence chart and the semantic.

Abstract: A linearized optical transmitter in which predistortion is employed to cancel both third and fifth order intermodulation distortion includes a modulated optical source responsive to a time varying electrical input signal to supply a time varying optical output signal containing multiple subcarrier signals. The modulated optical source is characterized by a non-linear transfer function such that intermodulation of the multiple subcarrier signals occurs, and for this reason, the optical transmitter further includes a predistortion circuit for supplying a predistorted signal comprising both the multiple subcarrier signals and intermodulation products substantially equal in magnitude and opposite in phase to those associated with the non-linear transfer function such that odd-order subcarrier intermodulation distortion products in the optical output signal are substantially canceled through the fifth order.

Abstract: An outdoor electronics enclosure which provides both weather protection and heat dissipation. The plastic enclosure is divided into two compartments. The first compartment has apertures in its exterior walls and contains an inner metal heat radiating box containing active electronic components. The second compartment is weathertight and contains passive components.

Abstract: The present invention provides a speech recognizer that creates and updates the equalization vector as input speech is provided to the recognizer. The present invention includes a speech analyzer which transforms an input speech signal into a series of feature vectors or observation sequence. Each feature vector is then provided to a speech recognizer which modifies the feature vector by subtracting a previously determined equalization vector therefrom. The recognizer then performs segmentation and matches the modified feature vector to a stored model vector which is defined as the segmentation vector. The recognizer then, from time to time, determines a new equalization vector, the new equalization vector being defined based on the difference between one or more input feature vectors and their respective segmentation vectors.

Abstract: An arrangement for adapting a PCM (pulse code modulation) switch to control and communicate with a CDMA (code division multiple access) cell site for communication the wireless CDMA stations that communicate with that cell site. A protocol converter converts between signals for controlling integrated services digital network (ISDN) stations and signals for controlling a cell site, so that the cell site operates as if it were being controlled by a wireless switching center and the switch acts as if it were controlling ISDN stations. In the switch, a switchable connection is established between land based inputs and intermediate ports and a separate set of permanent connections is established between the intermediate ports and the PCM/packet converters. Advantageously, a switch designed to serve ISDN stations can be readily adapted to serve cell sites for serving wireless CDMA stations.

Abstract: An amplitude and phase cancellation circuit for modifying or reducing the phase and amplitude of a signal includes a quadrature hybrid having four ports. A first port receives an input signal and a fourth port outputs an output signal derived from the input signal. The remaining two ports are connected to circuit sections having tuneable and adjustable components for selectively varying the phase and amplitude of the output signal. When the output signal is combined or mixed with an external signal, the circuit allows for selective adjustment or cancellation of components of the external signal by generating an output signal having a phase angle opposite to and amplitude equal to the external signal components for which cancellation is desired.

Abstract: A message sender (104) is equipped with a facility (250, 251) that automatically addresses the sender's messages and/or message components expressed in different media to the appropriate different addresses of the intended message recipient, in response to receiving an identification, such as the name, of the intended message recipient from the message sender. The message sender has an electronic directory (250) that lists, for at least some message recipients, a plurality of different telephone numbers and indicates for each telephone number the message medium or media that can be received at that address.

Abstract: A method and apparatus for processing source code in a language processing system with improved parsing based on prefix analysis. A method in accordance with the present invention includes the steps of identifying a previously-parsed prefix of a source code translation unit; creating a parser in a parser state corresponding to the identified prefix; and parsing a remaining portion of the translation unit after the prefix using the parser in the parser state corresponding to the prefix. In one embodiment of the invention, the step of creating a parser includes retrieving stored level-one subtrees corresponding to the top-level statements in the prefix. The level-one subtrees corresponding to the prefix may be stored in the form of a prefix tree along with the text of the top-level source code statements represented by the prefix and a parser delta indicating the effect of the code statements on the parser state.