Abstract: Methods and apparatus for allocating a system resource in a communication system having an interconnected set of modules and for which the system resource is allocated among the modules are disclosed. The interconnected set of modules may be a multi-shelf daisy-chained DSL access multiplexer (DSLAM), with each of the modules corresponding to a particular shelf of the DSLAM. The system resource is initially allocated among the modules in accordance with a predetermined allocation, e.g., a reserve pool is established with a first portion of the system resource and the remaining portion of the system resource is equally divided among the interconnected modules. The allocation of the system resource is then periodically updated based at least in part on measured characteristics of at least a subset of the modules, the measured characteristics being indicative of utilization of the initial allocation.

Abstract: An apparatus, method and system are provided for hand-off of a communication session utilizing ISDN multiway capabilities, in which the communication session of a mobile unit on a first call path is transferred from a serving base station to a target base station. The preferred system includes a switch coupled to a serving base station and a target base station, wherein the serving base station includes instructions to request a second call path to the target base station and to request a multiway feature. The switch then establishes the second call path from the serving base station to the target base station via the switch, and combines the communication session of the first call path with the second call path to form a multiway communication session.

Abstract: A logic circuit with improved performance when operating at the limits of the transistor's bandwidth. In particular, a latch includes a clocked trans-admittance stage circuit for receiving a voltage and producing a current output, and an active load, such as a trans-impedance stage circuit, connected to receive as input the current output of the trans-admittance stage circuit and produce a voltage output. Two independent trans-admittance and trans-impedance stages may be combined as a single latch pair. One or more latch pairs may be arranged in series as a cascaded chain and connected to the output current of a clocked trans-admittance stage latch.

Abstract: The inventors propose herein a novel band filter design for planar lightwave circuits. In one embodiment of the present invention, the band filter includes two waveguide grating routers connected by sets of substantially equal path length waveguides within each set separated on one side, wherein the waveguides of each set are formed such that optical signals having overlapping frequency ranges are propagated through adjacent waveguides. In addition, the waveguides of each set are spaced at their connection to the second waveguide grating router such that optical signals with predetermined optical frequency ranges are routed to selected, respective output ports. Some of the advantages of this novel band filter include compactness, sharp passband corners, and a lack of chromatic dispersion.

Abstract: A semiconductor waveguide includes a section containing free charge, either electrons or holes, which can be steered into or removed from the path of the beam under the control of electrical signals. The mobile charges come from a potential well which may be either filled or depleted under electrical control. When the well is filled, the charges speed the beam propagation, introducing a phase change. When the well is emptied the beam propagates with extra delay. The phase shifter allows very high speed modulation of the beam using low voltage and low power electronics. The device can be created using standard silicon processing techniques, and integrated with other optical components such as splitters and combiners to create amplitude modulators, attenuators and other optical devices.

Abstract: The scheduling of data transmissions for a CDMA system downlink or other type of communication network is implemented on a dynamic basis using a revenue-based policy. For a given transmission slot or other transmission interval, a maximum-rate user is identified from among a set of users requesting data transmissions, and a data transmission of the maximum-rate user is scheduled for the given interval. The maximum-rate user is identified based on application of coefficients of a revenue vector to corresponding feasible rates of the requesting users. The revenue vector is determined in an iterative manner using an adaptive algorithm which updates the revenue vector periodically to compensate for observed deviations between actual and target throughput, such that the deviations are reduced over time and the revenue vector converges to an optimal revenue vector.

Abstract: This invention is directed toward improving the subjective voice quality of a mobile to mobile phone call having tandem vocoder processing by modifying the spectrum of the voice signal before it is processed by the second vocoder to compensate for digital distortion which is generated by the second vocoder. An adaptive filter can be used to modify the spectrum of the voice signal. With this invention, the voice quality of a call from a first mobile phone to a second mobile phone has a quality that is substantially similar to the voice quality of a call from a mobile phone to a desk phone.

Abstract: A system and method is provided for measuring network round trip time by monitoring fast-response operations at one network endpoint, typically a client computer. A client computer of the system includes a network monitoring and analysis engine which monitors a sent packet for a fast-response operation. If a fast-response operation is detected, then the client computer assumes a server computer processed the packet substantially instantaneously. Thus, the processing time at the server computer is neglected as zero. The round trip time can then be approximated as the difference in time between when the client computer sent the packet and when the client computer received the response packet.

Abstract: A liquid electrical switch is disclosed that uses a plurality of droplets of conducting liquid to form an electrical path. In a first embodiment, at least a first voltage differential is used to create a separation distance between two droplets. The droplets are illustratively contained within a housing and surrounded by an immiscible, insulating liquid. In this embodiment, the at least a first voltage differential draws at least a portion of at least one of the droplets away from a second droplet, thus preventing electrical current from flowing from the at least one droplet to the second droplet. In another embodiment, the at least a first voltage differential is changed in a way such that at least one liquid droplet is made to come into contact with a second droplet, thus creating an electrical path between the two droplets.

Abstract: A tunable microlens uses at least two layers of electrodes and a droplet of conducting liquid. Such a droplet, which forms the optics of the microlens, moves toward an electrode with a higher voltage relative to other electrodes in the microlens. When calibration of the microlens is desired, an equal and constant voltage is passed over the first layer of electrodes and a different, constant voltage is passed over the second layer of electrodes such that the droplet of conducting fluid is adjusted to a calibrated position.

Abstract: A method and apparatus for assigning the data rate and/or power level to the mobile terminals without determining the highest theoretical system throughput, and without determining the highest weighted system throughput. An order is imposed on the terminals and the data rate and/or power covariance matrices are assigned such that the data rates of the terminals having a lower index in the order will not be decreased due to the presence of the terminals having a higher index in the order, and this is accomplished without changing the power covariance matrixes of the antennas involved in the communication with the lower index terminals. Thus, the assignment is made to the terminals based on the terminals requirements without regard to the interference introduced by the terminals with a higher index in the order since this interference will be compensated for by the compensation technique when the compensation technique process the terminals in accordance with the order.

Abstract: In an ad-hoc mobile network, a geometry-based routing protocol (GRP) is used to route traffic from a source node to a destination node. In the GRP, each node maintains a location list, which comprises location information for a number of nodes of the ad-hoc mobile network. Periodically, each node transmits to its direct neighbors (i.e., those nodes with which it has a point-to-point link) (a) its location, and (b) its location list. Each node that receives a location list from an adjacent node merges the received location list into its own location list such that location information for existing nodes, and/or newly identified nodes, is current.

Abstract: A method and apparatus for the characterization of an optical pulse includes splitting an optical pulse into two replicas separated by a delay, modulating at least one of the two replicas with a linear temporal phase modulation, measuring a spectrum of the modulated replicas, and characterizing the optical pulse using the measured spectra. In one embodiment of the present invention a spectral phase difference between the replicas is obtained from the measured spectrum using Fourier Transform Spectral Interferometry.

Abstract: An uplink and downlink channel structure supports a shared downlink data channel. The new structure accommodates advanced physical and Medium Access Control (MAC) layer techniques, such as incremental redundancy (IR), fast adaptation to channel conditions, and multiple input multiple output (MIMO) antenna configuration. The proposed changes are intended to lead to a downlink structure that achieves higher spectral efficiency for the packet oriented services over then shared downlink channel. Additionally, the new structure uses the base station transmit power information and of the channelization (OVSF) code space more efficiently.

Abstract: A network management system and technique, implemented in hardware and software, automates certain aspects of a network element configuration in a network of routers that use the OSPF protocol. The network management system uses network wide configuration information to detect configuration deficiencies and configuration related intra-element dependencies, and to then configure the elements automatically. This includes automatically detecting and configuring OSPF virtual links under several different scenarios, including (a) either minimal or complete (redundant) configuration of a router that is newly added to an existing network, and (b) reconfiguring of the routers in an existing OSPF domain, when either minimal or complete configuration is required. Minimal configuration is attained when at least one area border router (ABR) in an area is guaranteed to be connected to a backbone. In a complete configuration, all ABR's in an area are guaranteed to be connected to the backbone.

Abstract: A thermo-optic lens of the present invention includes a plurality of parallel heating elements having substantially constant center-to-center spacing and respective dimensions varying from the outermost heating elements to the innermost heating elements, and at least two conductive elements for providing a potential across the heating elements. The dimensions of the heating elements are varied such that a parabolic temperature distribution is generated within the thermo-optic lens. A dispersion compensator of the present invention includes a first and a second waveguide grating, each of the waveguide gratings having a first star coupler, an array of waveguides of increasing path lengths, a first end of each of the waveguides of the array of waveguides optically coupled to the first star coupler, and a second star coupler, a second end of each of the waveguides of the array of waveguides optically coupled to the second star coupler.

Abstract: An HDLC formatter and a message processing core exchange messages over a high speed message exchange interface. The interface includes a memory shared by the HDLC formatter and the message processing core. A handshaking arrangement is used to coordinate message storage and retrieval in the shared memory by the HDLC formatter and the message processing core with minimal utilization of processing resources of the message processing core. This handshaking coordination, together with the use of a message buffer accessed by the HDLC formatter to buffer channelized messages exchanged with the message processing core, facilitates message processing on multiple serial links (e.g., 3) over multiple timeslots (e.g., 256).

Abstract: A method is provided of informing mobile user terminals (12) camped on a cell of a base station (8) of a radio telecommunications network that a service is unavailable, such that a mobile user terminal (12) desirous of said service is handed over to another cell which provides said service. The method comprises informing the terminals (12) that selectably at least one of circuit-switched services (4) and packet-switched services (6) are unavailable.

Abstract: The invention comprises a system and method for transmitting and receiving between voice switches compressed multiplexed packets. The invention efficiently utilizes a Digital Signal Level Zero (DS0) to provide multiplexed voice traffic between two voice switches.

Abstract: A system and method for providing wireless time division multiplexed communications in which time is divided into a plurality of frames and each frame is divided into N data bursts, which has a first multiplexer defining a channel as a series of bursts that occur periodically every N bursts once per frame; a second multiplexer defining a sub-channel as every Mth burst of said channel; and a transmitter transmitting said channel and sub-channel from a first station to a second station. A new interleaving 0246/1357 method is used by the system which is just as good as the known 0123/4567 method when ideal frequency hopping is used, and 0246/1357 has better performance when non-ideal frequency hopping or no frequency hopping is used.