Abstract: Techniques for predicting RF signal propagation in indoor environments are disclosed. A typical technique comprises six distinct phases. In one phase, the mean wall separation, d, of one floor of a building is estimated. In a second phase, a reflection coefficient, s, is estimated for the floor in general. In a third phase, a number of trial RF propagation measurements are made to gather empirical data about the RF propagation characteristics of the floor. In the fourth phase, the mean wall separation, d, the reflection coefficient, s, and the trial RF propagation measurements are fit, using well-known techniques, into a wireless propagation model, such as ##EQU1## where P(r) is the measured or predicted power at a distance, r, from the transmitter, ##EQU2## and .xi. is the parameter that is fit to the empirical data.

Abstract: The system for automated determination of handoff neighbor list uses the data collected from mobile subscriber units to automatically update the handoff neighbor list. The mobile subscriber unit produces Pilot Strength Measurement (PSM) data that is indicative of the relative signal strength measured at the mobile subscriber unit from a plurality of pilot channels. The mobile subscriber unit transmits this data, along with a list of viable pilot channel candidates as determined by the mobile subscriber unit, to the base station serving the existing call. The system for automated determination of handoff neighbor list maintains a data structure that stores data indicative of the number of instances that a pilot channel is recommended, the sum of power levels that were measured by the various mobile subscriber units for these instances.

Abstract: A circuit board assembly includes an integrated circuit package. A first substrate has first and second surfaces. Each surface of the first substrate has a plurality of terminal pads. An integrated circuit device has first and second faces. The first face has a plurality of electrical interconnections to the terminal pads in the first surface of the first substrate. A heatspreader plate has a plurality of legs. For example, the heatspreader may be shaped like a table with four legs. The heatspreader may be formed of copper. The second face of the integrated circuit device is connected to the heatspreader plate by a first thermal interface material. Each of the plurality of legs is connected to the first surface of the first substrate by a second thermal interface material. The first and second thermal interface materials may both be, for example, a conductive silver-filled epoxy. The heatspreader provides an open package that is easily cleaned and drained.

Abstract: A communications connector assembly capable of meeting proposed Category 6 performance levels with respect to near end crosstalk. The assembly includes a wire board having a front portion, and a number of elongated terminal contact wires with base portions connected at one end to the board, and free end portions for electrically contacting a mating connector. The terminal contact wires extend parallel and co-planar with one another above the front portion of the board, and their free end portions project from the front portion of the board. The free end portions are configured to be deflected resiliently toward the board when the mating connector engages them in a direction parallel to the board. A crosstalk compensating device is associated with at least one of the terminal contact wires at a position where the wires are co-planar with one another.

Abstract: A composite gasket for the door of an outdoor, electronic component containing cabinet includes a known type of gasket including an elongated hollow tubing for mounting on a door jamb of the cabinet, and a supplemental gasket of an electrically conductive material fixedly secured to one side of the hollow tubing and coextensive therewith entirely around the periphery of the door jamb. The known gasket provides a weather seal for the door. The supplemental gasket spans the gap between the door and the jamb established by the weather gasket for electrically interconnecting the door to the jamb and for sealing the door joint against electromagnetic radiations. The supplemental gasket is disposed entirely within the weather sealed space of the cabinet when the door is closed, and is so arranged as to provide no interference with the weather seal formed upon closing of the door.

Abstract: Optical devices, such as wavelength routers, having a plurality of waveguides of differing lengths, with improved independence to temperature fluctuations. Improved temperature independence is achieved by varying the cross-section of the device waveguides. Cross-section variation can be implemented in one or more of the following ways: selectively applying a temperature-compensating material (e.g., a polymer) over portions of the waveguides, and/or varying the dimensions and/or compositions of the materials used in the waveguides, either along each waveguide or between waveguides or both. By carefully designing the devices, the temperature effects resulting from the different lengths of the different waveguides can be compensated to produce a relatively temperature-independent device.

Abstract: Apparatus for permitting any of a plurality of driver circuits to control a select lead. In the preferred embodiment, the plurality of drivers are in separate peripheral component interconnect (PCI) host bridges. The drivers when active are in one of two low impedance states. A resistor whose impedance is substantially less than the high impedance of a driver when in the inactive state is connected to ground and pulls the voltage on the select lead toward ground when none of the drivers connected to the select lead are active. Advantageously, a plurality of drivers can control a single select lead, and only a short time is required as a guard interval between the time that two different drivers control the select lead.

Abstract: Flow-induced noise affecting microphones used in such applications as cellular phones is reduced by providing a deflector, made of an acoustically transmissive, high flow resistance material, disposed at a certain distance from the microphone pressure sensing area. The distance between the pressure sensing are and the deflector may be determined experimentally in consideration of any space constraints imposed by the specific application, and for cellular phones in particular, is approximately as little as 2 or 3 mm from the outside surface of the deflector.

Abstract: A coherent optical system includes an optical coupler or combiner for combining a received upstream optical signal and an optical local oscillator signal. The coherent optical system further includes a coherent optical receiver which is configured to receive and process the combined optical signal from the optical coupler to retrieve upstream information from the upstream optical signal. In certain embodiments, the coherent optical communication system includes a central office having an optical source for generating a composite downstream optical signal made up of downstream optical signals of particular wavelengths (or sets of wavelengths).

Abstract: In a cellular system, channels are assigned for new calls using a cost-function-based dynamic channel assignment (CFBDCA) algorithm. In one embodiment, the CFBDCA algorithm is implemented in the cellular system's mobile switching center (MSC), which maintains a database containing one or more cost tables and a busy channel table. The entries in the cost tables reflect the costs of using a candidate channel in one particular cell of the cellular system, assuming that the channel is already being used in another particular cell. The entries in the busy channel table identify which channels are currently being used in which cells. The CFBDCA algorithm uses the cost tables and the busy channel table to generate cost of reusing the channel (CORC) values. Depending on the implementation, the CFBDCA algorithm of the present invention may or may not be used in conjunction with a measurement-based DCA (MBDCA) algorithm.

Abstract: A plug-in surge protector having an improved handle for facilitating and isolating the removal of an individual protector from a protector panel without interfering with adjacent protectors. The plug-in protector comprises a body having a front end and a rear end. Extending from the rear end of the body are terminals for plugging into sockets on a protector panel. Extending from the front end of the body is a handle having a reduced width and concave upper and lower surfaces. On the concave surfaces are horizontal teeth running across the width of the handle. It is preferable that the teeth are tilted towards the rear end of the body and against the direction of removal of the protector from the panel. The reduced width of the handle allows the removal of a single protector without touching or interfering with adjacent protectors plugged into the panel. The teeth on the handle increases the frictional surface area to facilitate removal of the protector from the panel.

Abstract: A method of preparing a supporting substrate of an optical subassembly for metal-oxide bonding an optical element to the substrate. The method includes providing a supporting substrate including a metalized region for metal-oxide bonding an optical element to the substrate and rinsing the substrate in a potassium hydroxide solution. The potassium hydroxide solution removes any excess metal oxide or other contaminants from the surface of the metalized region.

Abstract: Embedded systems employed in critical applications demand high reliability and availability in addition to high performance. Hardware-software co-synthesis is the process of partitioning an embedded system specification into hardware and software modules to meet performance, cost, reliability, and availability goals. The present invention addresses the problem of hardware-software co-synthesis of fault-tolerant real-time heterogeneous distributed embedded systems. Fault detection capability is imparted to the embedded system by adding assertion and duplicate-and-compare tasks to the task graph specification prior to co-synthesis. The reliability and availability of the architecture are evaluated during co-synthesis. On embodiment of the present invention, called COFTA, allows the user to specify multiple types of assertions for each task. It uses the assertion or combination of assertions that achieves the required fault coverage without incurring too much overhead.

Abstract: A method is described for the selection and assignment of keyboard access mnemonics and accelerator key combinations as part of the application software development process. After determining application functions and categories that require assignment, mnemonics and accelerators are assigned using pre-established recommendations, assignment rules and/or user assignment. If the assignments are made automatically, each function is first evaluated on the basis of usage likelihood and then prioritized before assignment begins in order to maximize the number and quality of successful assignments. In the alternative, assignments can be made on a function-by-function basis.

Abstract: An RF connector includes a shell that forms a cavity with the shell including external threads having a recessed portion therein which does not extend into the cavity so as not to cause a disruption in a signal transmitted through the connector. A locking slug is secured within the recessed portion for example by using an adhesive. The locking slug increases friction between the external threads and complementary internal threads of an interface plug to prevent the RF connector from loosening from the interface plug.

Abstract: A strain relief for an insulation displacement connector contains a cap section, a base section, and a base tab. The cap section is movable between an open position and a closed position and has a wire insertion channel for guidedly receiving a wire. The channel has an entrance aperture for entry of the wire into the channel. The open position facilitates entry of the wire into the channel. The base tab is upstanding from the base section and extends into the wire insertion channel when the cap is in the closed position. In this orientation, the wire in the channel is forced by the base tab into contact with a portion of an inner wall of the channel thereby forming a friction fit therebetween. Thus, the wire is restrained in the channel and strain relieved.

Abstract: The present invention includes a MZI comprising a pair of folded waveguides disposed between a pair of couplers. Each folded waveguide comprises a pair of segments intersecting at a reflector. The respective reflectors are different distances from the couplers to provide a major portion of the differential path length between the two arms. In a preferred embodiment, the reflectors are polysilicon mirrors and can be formed by etching through the intersecting waveguides and depositing polysilicon. The result is a compact MZI that can be used as a multiwavelength reference for a laser light source on a common silicon optical bench chip.

Abstract: An improved optical fiber device includes a length of optical fiber having a longitudinally tapered region for causing a portion of light signals guided by the fiber to emerge outside of the fiber. The tapered region is surrounded by a coating that operates on the portion of the light signals emerging from the fiber to modify their propagation properties. The tapered optical fiber device can be used in an optical fiber system which includes at least one source of light signals, wherein the optical fiber device is disposed in the path of light signals from the source.

Abstract: A scalable overflow clamp for controlling the level of allowable digital signal overflow in a gain scaler/summer having an initial full-scale range and a feedback path for establishing a feedback gain. The clamp includes a range scaler for determining the feedback gain and generating a modified full-scale range relative to the feedback gain. The modified full-scale range defines a substantially constant overflow capability relative to the feedback gain. An overflow detector senses the overflow conditions and a selector responsive to the overflow detector utilizes the modified full-scale range when overflow conditions are sensed.

Abstract: A circuit, such as a phase-lock loop (PLL), has an oscillator having a plurality of operating curves. During circuit auto-trim operations, the oscillator is automatically trimmed to an appropriate oscillator operating curve for use during normal circuit operations. In particular PLL embodiments, the PLL is a charge-pump PLL having a phase/frequency detector (PFD) that generates error signals based on comparing an input signal and a PLL feedback signal; a charge pump that generates amounts of charge corresponding to the error signals; a loop filter that accumulates the amounts of charge to generate a loop-filter voltage; and a voltage-controlled oscillator (VCO), where the VCO output signal is used to generate the PLL feedback signal. During normal PLL operations, the loop-filter voltage is applied to the voltage input of the VCO.