Abstract: A telephonic handset comprises an active noise reduction (ANR) system. The ANR system comprises a reference microphone and an IIR filter. The IIR filter is receivingly coupled to the reference microphone with respect to noise reference signals, and it is transmittingly coupled to the receiver transducing element of the handset. The ANR system is configured as a fixed feed-forward noise cancellation system. Preferably, the IIR filter has a transfer function derived, in part, from the open-loop gain of a feedback noise cancellation system. In specific embodiments of the invention, the noise reference microphone is situated so as to sample the ambient noise field near the front face of the receiver, but without directly sampling the noise field on the front face.

Abstract: An omnidirectional video camera captures images of the environment while moving along several intersecting paths forming an irregular grid. These paths define the boundaries of a set of image loops within the environment. For arbitrary viewpoints within each image loop, a 4D plenoptic function may be reconstructed from the group of images captured at the loop boundary. For an observer viewpoint, a strip of pixels is extracted from an image in the loop in front of the observer and paired with a strip of pixels extracted from another image on the opposite side of the image loop. A new image is generated for an observer viewpoint by warping pairs of such strips of pixels according to the 4D plenoptic function, blending each pair, and then stitching the resulting strips of pixels together.

Abstract: A coupler includes a first set of ports coupled to a first ring, a second set of ports coupled to a second ring, and a plurality of connecting elements coupled between the first and second rings. The coupler provides low loss insertion and high port isolation and may be used as a standalone coupler or as an elementary device for building Butler matrices of varying configurations.

Abstract: A method and apparatus is proposed for use in a communication system in which an optical communications path including a plurality of optical spans, each of the optical spans contributing nonlinear distortions to an optical signal passing there-through includes, providing a dispersion pre-compensation to the optical signal in the optical communications path, such that the limiting nonlinear effect that produces signal distortions for long-haul transmission is suppressed, prior to transmission through a plurality of optical spans, and providing a dispersion post-compensation to the optical signal in the optical communications path after transmission through the plurality of optical spans.

Abstract: Systems and techniques for generating optical pulses exhibiting a progressive phase shift, and the use of those pulses to transmit data, are described. One embodiment of the invention employs a Mach-Zehnder modulator using electrical signals chosen to introduce a predetermined frequency shift at the center of each pulse generated by the pulse generator. This frequency shift is achieved by introducing a timing difference between the electrical input signals. Another embodiment of the invention employs a chirp free pulse generator and a separate phase modulator to induce the desired frequency or phase shift. These progressively phase shifted pulses may be further modulated to transmit data by introducing phase or amplitude modulation on the optical pulses, depending on the data to be transmitted.

Abstract: Overhead voltage is allocated in a telecommunication system among different AC signals, such as POTS, on-hook transmission POTS, PPM and XDSL signals, communicated between a telephonic switch and a user device. The allocation is based on the available overhead voltage, the condition, such as impedance, of the line carrying communications to the user, and which of the signals are to be communicated.

Abstract: An apparatus for performing optical routing includes a metal layer having first and second sides, a regular array of structures positioned along the first side, and an input optical waveguide positioned to illuminate a portion of the first side. The illuminated portion of the side is adjacent to ones of the structures. The apparatus also includes a plurality of output optical waveguides positioned to receive light radiated from portions of the metal layer not illuminated by the input optical waveguide.

Abstract: A system and method of replicating changed data between an active process and a standby process is provided. The active and standby processes each include an application and a processor having memory. The method includes organizing active and standby processor memories into regions, with each region including one or more tuples, datamarking the tuples having changed data in the active processor corresponding to the active application, and transferring copies of the changed data from the active process to the standby process to replicate data between the active and standby processors. The system includes means for datamarking changed data and transferring copies of the changed data between active and standby processes having active and standby processors configured as mated pairs.

Abstract: Telephone numbers are omitted from a communications device (200) or line (110b), thereby inhibiting incoming calls. Outgoing calls are permitted on the line or communications device and are facilitated in part by an equipment identifier (122b, 222) used in a telecommunications network. A surrogate telephone number, which may already be assigned to a customer, is used for billing, caller identification and other functions. The equipment identifier is used for maintenance, administration and other functions associated with the communications device or line. A telephone number is temporarily made available to the communications device or line for a predetermined period of time upon request by a user. This advantageously reduces the number of telephone numbers required in a telecommunications network.

Abstract: Systems, methods, and software are disclosed for synchronizing data among network elements of a telecommunication management network. In a data synchronization system, a mapping system receives a first data set from a first network element and receives a second data set from a second network element. The mapping system processes the first data set to identify a first object, and processes the first object based on mapping rules to identify an associated second object in the second data set, and map the first object and the second object. A comparison system then processes the first object and the second object as mapped to identify differences between the objects, and generates information indicating the differences. An alignment system processes the first object and the information indicating the differences to generate new object data used to adjust the first object stored in the first network element.

Abstract: Systems and methods are disclosed for adding attachments to voice calls. A communication system for the invention includes a file server and a switching system of a circuit-based network. During a voice call connected between a first station and a second station over the circuit-based network, the switching system detects a code entered by the user of the first station. Responsive to detecting the code, the switching system transmits a query to the file server. The file server processes the query to locate one or more files stored in the file server. The file server then transmits the located file to the switching system. The switching system plays the file to the second station over the connection for the voice call.

Abstract: Systems and methods are disclosed for serving VoIP emergency calls. In one embodiment, a call control entity is placed between PSAPs of an emergency services network and the IP network transporting VoIP calls. When the call control entity receives a VoIP emergency call and its associated user ID, the call control entity assigns a TDN to the emergency call and associates the assigned TDN to the user ID. The emergency call and the TDN are then extended to a PSAP to handle the emergency call. If the emergency call is disconnected from the PSAP, the PSAP operator is able to dial the TDN to provide a call-back function. The call control entity receives the call-back attempt to the TDN from the PSAP, identifies the user ID associated with the TDN, and routes the call-back attempt to the user ID to reestablish a call between the PSAP and the user.

Abstract: A distinct-count estimate is obtained in a guaranteed small footprint using a two level hash, distinct count sketch. A first hash fills the first-level hash buckets with an exponentially decreasing number of data-elements. These are then uniformly hashed to an array of second-level-hash tables, and have an associated total-element counter and bit-location counters. These counters are used to identify singletons and so provide a distinct-sample and a distinct-count. An estimate of the total distinct-count is obtained by dividing by the distinct-count by the probability of mapping a data-element to that bucket. An estimate of the total distinct-source frequencies of destination address can be found in a similar fashion. By further associating the distinct-count sketch with a list of singletons, a total singleton count and a heap containing the destination addresses ordered by their distinct-source frequencies, a tracking distinct-count sketch may be formed that has considerably improved query time.

Abstract: Systems and methods are disclosed for changing attributes of voice calls. During a voice call over a connection of a circuit-based network between a first station and a second station through a switching system, the switching system receives audio from the first station. The switching system also detects a code entered by the user of the first station. Upon detecting the code, the switching system changes one or more attributes of the audio received from the first station to generate audio with changed attributes. For instance, the switching system may raise or lower a volume of the audio, may raise or lower the frequency of the audio, may add or remove background tones, or change other attributes. The switching system then transmits the audio with the changed attributes to the second station.

Abstract: A method and apparatus for measuring the group delay of a device are provided. The temporal and spectral intensities of optical pulses are measured after propagation in the device and the group delay of the device is determined using the measured intensities.

Abstract: The cellular call redirection system enables a subscriber to redirect all incoming calls directed to the subscriber's cellular telephone to an automated message system for a predetermined period of time. In addition, the calling party is connected to a voice announcement system which plays a message to the calling party to inform the calling party that the call has been redirected and provides information regarding the time remaining before the call redirection feature is automatically deactivated. This provides the calling party with an indication of the future time at which the subscriber is likely to be available to receive incoming calls. In addition, the cellular call redirection system maintains a count or queue of redirected incoming calls to thereby enable the subscriber to determine the number and identity of the calling parties who have attempted to contact the subscriber during the period that this feature has been activated.

Abstract: Systems for, and method of, determining propagation characteristics of a photonic structure having a transverse N-fold symmetry. In one embodiment, a system includes: (1) a numerical analyzer that employs a leading order of a systematic homogenization expansion having multiple scales to develop an angularly averaged indexed profile for the photonic structure and (2) a leading order corrector, associated with the numerical analyzer, that further employs the homogenization expansion to refine an imaginary part of an effective index of refraction of the photonic structure.

Abstract: A new algorithm for clock offset estimation for resources distributed across a network (such as the Internet). By exchanging a sequence of time-stamped messages between pairs of network nodes and separately estimating variable delays for each message direction, present inventive embodiments provide estimates for clock offset between node pairs and the bias of such estimates, thereby to permit more accurate correction. Present inventive algorithms operate in a variety of peer and server network configurations while providing significant improvement in convergence speed and accuracy.

Abstract: A synchronization of a pilot assisted channel estimation orthogonal frequency division multiplexing can be achieved by receiving a signal containing pilot symbols, providing an initial time and frequency synchronization to the signal, phase rotating the signal across time, transforming the signal with a fast Fourier transformation, phase rotating the signal across frequency, extracting the pilot symbols and generating a channel estimator. The phase rotating across time and the phase rotating across frequency are controlled by a phase rotation controller in accordance with the channel estimator. The initial time and frequency synchronization synchronizes the signal such that intercarrier interference effects and intersymbol interference effects are negligible. The signal may include plural carrier frequencies each having an arrival timing offset and a frequency offset. The signal may also include delay spread or Doppler spread.

Abstract: A method of transferring a call established between a first communications device and a second communications device from the second communications device to a third communications device. The method includes negotiating media description between the first communications device and the third communications device to establish a transferred call capable of handling media which can be different than that handled by the original call.