Abstract: A distributed Bragg reflector laser is fabricated wherein material defects are produced in the laser's tuning waveguide region. The defects may be created by introducing impurities into the region. The defects increase the non-radiative recombination rate of injected carriers, thereby decreasing FM efficiency and improving RF performance. Injected carrier electrons are substantially separated from injected carrier holes to reduce bimolecular and Auger recombination rates, thus improving tuning range.

Abstract: A Code Division Multiple Access system and method of operation provides reduced interference for received signals and improved signal acquisition and processing with reduced computational complexity. The system includes a base station coupled to an antenna array of at least two or more antennas and serving a plurality of users. A receiver in the base station includes a universal inverse cross-correlation matrix coupled to the antenna array, a signal acquisition and a signal processing circuit serving each user. Each signal acquisition circuit comprises a series of delay stages in which the incoming antenna signals in each stage are correlated with a spreading code and combined in a multiplier coupled to the universal inverse cross-correlation matrix which facilitates improved time delay estimation for signal acquisition.

Abstract: A programmable broadband N×N cross-connect switch includes an N×N wavelength coupler combined with N tunable lasers, N modulators and N optical receivers. Each of the N tunable lasers can selectively produce N different wavelengths. The coupler couples the N wavelengths to the N modulators. The N modulators modulate the N wavelengths using N input electrical signals, each modulator being selectable by choosing a laser wavelength. The N optical receivers receive and detect the N modulated wavelengths to produce N output electrical signals therefrom, each receiver receiving and detecting a different one of the N different wavelengths. By selecting a laser wavelength a particular modulator and receiver is selected so that a modulated signal, formed at the selected modulator when an input electrical signal modulates the selected wavelength, is switched to the selected receiver.

Abstract: A wave division multiplexing system in which low frequency intensity modulation of the optical channels is avoided in order to reduce or substantially prevent inter-channel cross-talk of low frequency telemetry signals by phase modulating the low frequency telemetry signal so as to recover the transmitted signal at the receiver. The system includes multiple transmitters and receivers. Each transmitter includes an optical source, such as a laser, a radio frequency generator having a low frequency telemetry signal impressed thereon, and an optical phase modulator. The phase modulated low frequency telemetry signal generated by each transmitter is combined using a multiplexer before being amplified and transmitted through a single optical fiber. A demultiplexer receives the transmitted signal and separates it into respective optical channels based on the particular frequency of each transmitter. Respective signals for each optical channel are transmitted to an associated receiver.

Abstract: The wireless communication system includes antennas having electrically controllable downtilt angles and downtilt controllers associated with each antenna. The downtilt controllers receive instructions from a main controller, and adjust the downtilt angles of the associated antennas in accordance with the received instructions.

Abstract: A customer signature or other type of record in a database system is updated using an event-driven estimator based on a model of time-dependent behavior. In a preferred embodiment, a current version of a record affected by a given transaction is retrieved from a memory of the system and an event-driven estimator of at least one of a transaction rate and a period probability for the record is determined based at least in part on a dynamic Poisson timing model having a number of periods and corresponding period-based transaction rates associated therewith. The event-driven estimator may be configured so as to generate an estimated transaction rate {circumflex over (&lgr;)}j,n for period j and a given transaction n, and then to generate an estimated period probability {circumflex over (&pgr;)}j,n for period j as {circumflex over (&lgr;)}j,n/&Sgr;k{circumflex over (&lgr;)}k,n. An updated version of the record may then be generated based on the event-driven estimator.

Abstract: Data compression achieved by set partitioning of hierarchical trees is made more efficient by a family of related traversal schemes which act upon the tree structure and the significance values derived from the tree structure. The tree structure may be traversed in any of a number of sequences. In accordance with significance tests applied to the node data, bits are produced or not. The order in which the bits are produced may be freely chosen. Trees are traversed and bits are emitted which describe the relative magnitude of coefficients in the sub-trees of the current tree-node. The manner of traversal can either be known to the remote decoder or can be derived from the incoming data stream. The encoding scheme typically specifies all bits emitted by a given node v as a function of the traversal of its parents, the bit-plane b, the coefficient value c of v, the significances B1(v) and B2(v), and whether the parent node p still emits B2(p).

Abstract: A computer implemented method and apparatus utilizing a multi-diversity synchronization technique for improving time synchronization in wireless applications, such as TDMA applications is disclosed. The multi-diversity synchronization technique utilizes cross-correlations between multiple diverse received signals to determine relative offsets between the signals. The signals are then time aligned. An absolute synchronization word location is determined using the time aligned signals and is used along with the relative offsets to determine respective synchronization word locations for each received signal in an accurate, efficient and improved manner.

Abstract: A system and method that enables a calling party to verify delivery and/or cancel stored facsimiles. This advance is achieved by a voice mail system that receives incoming telephone calls and compares an incoming caller ID with caller ID's stored in conjunction with previous faxes. If a caller ID of the incoming call matches a caller ID in the database, (i.e., the calling party has previously left a fax) then the calling party is presented with a menu of options. The menu may include determining whether the called party has accessed the voice mail system but did not print or delete the fax message, and if the fax has not already been deleted, the calling party may delete the fax.

Abstract: A distortion reduction system uses upstream signal information from carrier frequencies in a signal to be amplified, to determine at least one frequency for the distortion generated by an amplifier amplifying the signal. A sample of an output is taken, and a distortion detection circuitry is used to detect the amplitude of the distortion at least at the one frequency. In response to the amplitude of the distortion at the one frequency, the processing circuitry provides gain and/or phase control signal(s) to adjust the relative phase and/or gain between combining distortion products to reduce the amplitude of the distortion.

Abstract: For a large system having an associated monitoring system with one or more user interfaces that each requires a large amount of direct user interaction, a liaison interface is provided between the user and the existing user interfaces. The liaison interface requires much less direct user interaction by taking the place of the user in the extensive direct interaction required by the existing user interfaces.

Abstract: Traffic demands are routed in a ring network by first determining an inter-ring path for a given demand, and then independently determining an intra-ring path for the demand on each of the rings in the inter-ring path. The intra-ring path provisioning is fully decoupled from the inter-ring path provisioning, such that the demand can be routed more quickly and efficiently. For example, both the routing direction and the interworking nodes for a dual ring interworking (DRI) connection can be determined independently for each of the rings of the inter-ring path. The invention may be implemented in the form of a hybrid centralized/distributed network architecture, in which a central operations system or other central controller determines the inter-ring path by applying a shortest path algorithm to a ring graph in which nodes represent rings in the network and links represent ring interconnections in the network.

Abstract: A system and method for provisioning cable telephone service in a cable communication system that is at least partially integrated with a telephone network. The cable communication system includes a head end Remote Digital Terminal (RDT) respectively communicating with a broadband network, a telephone switch and a customer premises Integrated Service Unit (ISU), and also includes an Order Management Center (OMC) associated with the RDT, the switch, or both. To implement telephone service to customer premises equipment adapted for communication with the ISU, the RDT is notified of a new service request by way of a service request message sent from the ISU to the RDT, and the switch is notified of the new service request by way of provisioning information sent from the OMC to the switch via an Element Management System (EMS) associated with the switch.

Abstract: Improved telecommunication apparatus is realized with a structure that is tailored to provide an ID signal to the telecommunication network, which signal uniquely identifies the apparatus. The ID signal can be communicated to the network under control of the apparatus, or polled by the network The apparatus includes a second port through which communication services are provided to a customer, and the ID signal can be sent to that second port as well. The apparatus further includes circuitry for processing signals flowing between the two ports, allowing the characteristics of the signal to change and thereby provide for format conversions, encryption, and other capabilities.

Abstract: An apparatus comprising a tunable liquid microlens that includes a transparent supporting layer and a transparent photoresponsive layer disposed on a first surface of the supporting layer. A droplet of a transparent liquid is disposed on the photoresponsive layer. The photoresponsive layer separates the supporting layer and the droplet. At least a portion of the photoresponsive layer that contacts the droplet may be selectively irradiated by at least one light source such that a contact angle between the droplet and the photoresponsive layer may be varied and the droplet may be repositioned along the photoresponsive layer. In this manner, at least one of a focal length and a lateral position of a focal spot of the microlens may be adjusted directly by irradiation with a light beam.

Abstract: A method and apparatus are disclosed for remotely managing network elements in a distributed computing system. The distributed computing system utilizes a software entity, such as an operating system, to manage the location of, and communication with, distributed resources in the distributed computing system. A network manager and/or SNMP agents can interact with distributed elements to obtain desired management information independent of the location of the distributed elements. Thus, master agents can communicate with managed network nodes without adhering to the intricate requirements of the SMUX or DPI protocols. SNMP MIBs are implemented as hierarchical file systems, comprised of a tree of file-like objects, that may be accessed through a namespace. The SNMP MIB namespace allows the network manager, master agent and SNMP agents to access each resource, including SNMP MIBs, in a uniform, file-oriented manner.

Abstract: A tunable liquid microlens includes an insulating layer, a droplet of a transparent conducting liquid, and a lubricating layer disposed on a first surface of the insulating layer and between the droplet and the insulating layer. The microlens also includes a plurality of electrodes insulated from the droplet by the insulating layer and the lubricating layer, the plurality of electrodes being disposed such that they may be selectively biased to create a respective voltage potential between the droplet and each of the plurality of electrodes, whereby an angle between the droplet and a plane parallel to the first surface of the insulating layer may be varied and the droplet may be repositioned relative to the insulating layer.

Abstract: A method that selects one of a plurality of priority schemes for scheduling messages for one of cyclically repeating sets of time slots of a control channel based on at least one of a plurality of characteristics of the state of the control channel. The state of the control channel is all information regarding what has arrived, what is queued, and what has been transmitted. This includes the status of the queues, the messages awaiting transmission, along with their type and the time they have been waiting, the sequence of past transmissions, as well as other information.

Abstract: Quasi-Walsh function systems are developed which allow multiple access as well as spectral spreading for interception and jamming prevention. Mutual interference is minimal due to orthogonal spreading. High signal hiding capability occurs by utilizing a large number of distinct orthogonal codes. An encoding algorithm is presented which allows a simple way of “keeping track” of the different systems of Quasi-Walsh systems as well as determining appropriate values for given users at specified chip values.

Abstract: A apparatus linearizing and technique for linearizing a non-linear power amplifier used in a transmitter of, e.g., a TDMA mobile wireless telephone. Linearization of the non-linear amplifier by changing the shape of the input signal is performed when the input signal level is high, thus increasing efficiency or reducing power consumption at that time, albeit at the cost of increased inter-symbol interference (ISI). However, since the input signals at that time are at a high level, the increased ISI can be tolerated and adjacent symbols can still be distinguished from one another. The invention allows use of a non-linear power amplifier which typically enjoys a lower current consumption than that of a linear power amplifier, thus increasing the time between battery recharges and/or reducing the overall size of the wireless telephone device. The power amplifier is operated in a linear mode when transmitted power is low, thus allowing differentiation between adjacent symbols (i.e., improvement of ISI).