Abstract: The wireless CDMA system includes a base station which generates a configuration channel as one of the forward control channels. The message slots in the configuration channel only include overhead messages. The base station also generates at least one other forward control channel, but these other forward control channels do not need to include overhead messages in any of their message slots. The mobiles in the system determine the location of the configuration channel from information in a sync channel generated by the base station. By camping onto the configuration channel, a mobile can quickly obtain the overhead parameters in the overhead messages. Because obtaining overhead parameters and keeping an updated version of the overhead parameters is an important factor in overall performance, the significant decrease in overhead message access time provided by the provision of the configuration channel greatly improves performance.

Abstract: A contention-based network which allows real-time traffic to be assembled into multiple linked-list chains. A time separation is enforced between the various multiple chains, which are limited to a predetermined maximum number of stations that each can have in order to allow non-real-time stations to obtain timely access to the medium. Ones of the multiple chains may also be joined into a single chain. Blackburst contention is used to enable a chain to be reconstituted robustly from non-anticipated interruptions, such as the failure of one of its stations.

Abstract: An improved keyboard, and a data terminal incorporating same, is disclosed. The present keyboard advantageously includes a keyboard membrane having, on an upper side, a plurality of raised regions upon which character designators can be placed. A plurality of upper key members are disposed on a lower side of the keyboard membrane. Each upper key member is advantageously structurally adapted to return itself, after removal of an actuating force, to an unactuated position. The raised regions on the upper side, and the upper key members on the lower side of the keyboard membrane are advantageously molded from a single elastomeric layer, thereby replacing hundreds of parts in conventional computer-style keyboards using sliding-plunger type key mechanisms. A plurality of lower key members are disposed on a circuit board underneath the keyboard membrane. The lower key members are structurally adapted to prevent “rock over” when a user depresses a raised region somewhat off-center.

Abstract: A system and method for increasing the speed of flow of a quantity of data or of a plurality of data types through a communication system. The communication system comprises a plurality of switches including a source and a sink, each of the switches connected to a neighboring switch by a communication link having a capacity, each of the links having a pair of queue buffers, and one queue buffer of each pair of queue buffers is located at each switch connected by a link. For a single data type, a flow is computed for each link as a function of a last previous amount of flow across the same link. In the multi-data type case, a weighted queue difference is computed as a function of a last previous amount of flow between the same pair of queues and an amount of flow fi of said data type i is routed across each said link such that &Sgr;1≦i≦Kfi (&Dgr;′i(e)−fi) is maximized.

Abstract: A recursive, single-wrong-turn (SWT) decoding method and Viterbi decoder which requires no additional circuitry or processing to keep track of a running list of the L best paths. If the most likely (ML) path fails frame quality metric tests, a search is made through a trellis using an existing survivor (trace back) information stored in a survivor (trace back) memory. An iteration in the recursive algorithm includes tracing back along the ML path to a particular stage, then deviating from the ML path and following the survivor information along that new deviant path, and finally checking the fully decoded frame to see if the frame quality metrics are acceptable for the frame. These same trace back steps can be performed for every stage in the trellis, deviating from a different stage on the ML path each time.

Abstract: A polarization-mode-dispersion emulator in accordance with the principles of the present invention includes a plurality of PMD-generating stages aligned in cascade so as to form a clear light-path through the stage concatenation. Each PMD-generating stage includes an optical birefringent crystal or crystals for the purpose of imparting differential group delay and a polarization-rotating plate such as a half-wave waveplate for the purpose of imparting state-of-polarization rotation from one PMD-generating stage to the next. The polarization-rotating plates are mounted to rotation apparatuses and a controller coordinates the relative rotation of each waveplate for the purpose of generating PMD in a controlled manner.

Abstract: A secondary protection device for protecting a circuit. The device includes a first positive temperature coefficient (PTC) resistor, a bidirectional zener diode and a second PTC resistor connected in series across input terminals. Output terminals are connected across the bidirectional zener diode for providing a protected output to the circuit. A second zener diode is coupled between one end of the bidirectional zener diode and a ground potential for limiting an output voltage to the circuit.

Abstract: Drop testing is performed by controlling the position of a product to be tested with respect to the drop surface until just before the initial impact and then the product is allowed to impact like a free body. Advantageously, realistic, controllable, and substantially repeatable free drop testing can be achieved. In one embodiment of the invention the product is suspended at an angle from a falling structure, e.g., using at least one string or wire, and the suspending material is effectively released just prior to initial impact. By effectively released it is meant actually released, or the effect of the suspending material is essentially negligible, e.g., where the suspending material produces a very low restitutional force when deformed, such as a weak rubber band. The suspension of the object is arranged in such a way that initial impact occurs at the desired point on the product.

Abstract: A method and apparatus for controlling bit slips in a high-speed, two-way, communications channel. More particularly, the entire communications system, comprising, inter alia, a receiver, a transmitter and the physical communications channel is operated as a feedback loop. That is, the detection of bit slips is performed continuously in the receiver and a bit slip signal is generated that indicates the number of bit slips and the direction, i.e., forward or backward, of the bit slip. Thus, the bit slip signal is communicated to the transmitter and certain actions are performed to introduce bit adjustments in the bit stream to eliminate the effects of any future bit slips. The bit slip signal contains an indication of the number of bit slips which have occurred, the time between bit slips, and the direction of the slip. As a function of this information from the bit slip signal, bit adjustments are made in the communications stream to correct for the bit slips and mitigate any effect in future transmission.

Abstract: In a method for admitting new connections based on measured quantities in a wireless communications network having a base station and remote hosts, the base station measures and computes performance metrics to determine whether admission of the new connection could cause a failure to meet the Quality of Service (QoS) promised to already admitted connections. Only if the QoS can be maintained is the new connection is admitted. In one embodiment, the base station may optionally disconnect one or more already admitted lower priority connections if doing so will allow a higher priority new connection to be admitted without loss of QoS to the remaining already admitted connections. In one embodiment, each connection request specifies the average bit rate required and a traffic burstiness factor, the base station measures the number of bytes sent by each connection for a certain period of time and a burstiness factor for the traffic in either direction.

Abstract: A weather resistant cabinet for housing electrical equipment includes a one-piece, unitary tubular housing. The tubular housing has two open ends and is preferably formed from aluminum using a deep-drawing process. Two covers are attached to the two open ends of the tubular housing. The two covers include heat sinks and are preferably formed from aluminum using an extruding process. The covers are attached to the tubular housing using either mechanical fasteners and a gasket, or by a dip-brazing process.

Abstract: An adaptive filter (and a corresponding adaptive filtering method) for use in an echo cancellation environment, comprising a finite impulse response filter having a vector of adaptive coefficients, and an adaptive coefficient vector update module which modifies the vector of adaptive coefficients in response to an error signal and based on a predetermined probability density function for said error signal. In accordance with several illustrative embodiments of the present invention, the probability density function is advantageously non-Gaussian, and has certain advantageous characteristics which provide for robustness in the adaptive algorithm based thereupon.

Abstract: A semiconductor waveguide device and method for forming the same provide an InAlAs film as an etch stop layer. The InAlAs film does not etch in the CH4/H2 etch chemistry used to produce the device using reactive ion etching techniques. The etching process etches the waveguide layer and cladding layer or layers formed above the InAlAs layer, and exposes the InAlAs etch stop film to produce a waveguide device having desired physical characteristics.

Abstract: An optical fiber cable having a core which includes at least one optical fiber transmission medium, a sheath system which is disposed about said core, and a filling material disposed within said core. The filling material of the optical fiber cable includes both a hydrocarbon carrier means, and a thickening system disposed within the hydrocarbon carrier means. The thickening system may include an inorganic constituent, either alumina or fumed alumina, and a polymer.

Abstract: A method and system for testing circuit clusters in a boundary scan environment identifies the circuit clusters and corresponding neighboring boundary scan elements, and generates one or more test vectors to be applied to the cluster under test. The generated test vectors are serialized and input into an identified boundary scan element connected to the cluster being tested in the form of a boundary scan test chain. The output of the applied test vectors is observed from an output of another correspondingly identified boundary scan element connected to the cluster under test. During generation of test vectors a list of faults for detecting by each generated vector is maintained such that the observed output can be used to diagnose faults at the component level within the identified cluster.

Abstract: An arrangement for providing secure transmission of information. The bulk of the information is transmitted over non-secure channels such as broadcast media which terminate on a plurality of receiving stations. However, a residue of data is transmitted over a protected channel, such as a point-to-point channel, established for example, by a telephone connection. Interception of a complete message, when only the bulk of the message is available, becomes very difficult. It becomes even more difficult if scrambling arrangements are used to select the particular bits of the data message that are transmitted over the secure channel. It becomes still more difficult, if the data transmitted over the secure channel, itself, alters the scrambling algorithm.

Abstract: A system includes a first virtual end point processor (332) operably coupled to a plurality of channel elements (304) and a second virtual end point processor (340) operably coupled to a plurality of frame selectors (314). The system also includes at least one signaling manager (318, 334) that is arranged and constructed to establish a communication path that terminates at the first virtual end point processor (332) and the second virtual end point processor (340) prior to receiving a request for resources for a data call, such that set-up time for the data call through a wireless network is reduced.

Abstract: An analog-to-digital (A/D) converter system which converts an attenuated analog input signal into a digital value and shifts the position of the digital value within the digital output depending on the attenuation of the analog input signal. For example, in response to an analog input signal which saturates a first A/D converter, a second A/D converter receives and converts an attenuated analog input signal, and the output of the second A/D converter is used to produce the more significant bits of the digital output value to convert a higher amplitude range (power or voltage level range) for the analog input signal. In another example, a level detector can detect the amplitude of the analog input signal and provide an indication of the amplitude of the analog input signal. In response, the analog input signal is attenuated and provided to an A/D converter.

Abstract: A system and method that simulates actual use of appliances and devices in a building learns actual usage patterns over an extended length of time. By replaying such learned sequences to controlled devices whereby the devices are turned on at off, the on/off sequences appear more natural making a building or dwelling appear to be occupied. The realistic control of devices mimics occupancy of a dwelling. In a learn mode, an intelligent control system records and stores the on/off events of controlled devices in the dwelling. In a run mode, the intelligent control system replays the on/off events thus reflecting the usage patterns of the resident.

Abstract: A coupled data network with an accounting system is disclosed. The coupled data network includes a foreign network and a home network. The foreign network includes a base station with an access hub and a foreign mobile switching center with a serving registration server, the access hub including a serving inter-working function, the serving inter-working function including a foreign accounting collection module. The home network includes a home mobile switching center with a home inter-working function, the home inter-working function including a home accounting collection module. An end system is a subscriber to the wireless data network and coupleable to the foreign access hub. The home and serving accounting collection modules collect accounting data on message traffic transported between the end system and a communications server through the home inter-working function and through the serving inter-working function.