Abstract: Systems and methods for synchronizing a clock at a customer premises equipment (CPE) location with a master clock at a central office (CO) location are described. One embodiment is a method that comprises receiving, by a time-of-day transmission convergence (ToD-TC) module in the CPE, ToD information relating to the master clock. Based on the received information, time stamps are applied to reference data samples. The method further comprises transporting the ToD information by transporting the reference data samples with applied time stamps and utilizing time stamps of the reference data samples to synchronize the CPE clock with the master clock.

Abstract: Systems and methods for synchronizing a clock at a customer premises equipment (CPE) location with a master clock at a central office (CO) location are described. One embodiment is a method that comprises receiving, by a time-of-day transmission convergence (ToD-TC) module in the CPE, ToD information relating to the master clock. Based on the received information, time stamps are applied to reference data samples. The method further comprises transporting the ToD information by transporting the reference data samples with applied time stamps and utilizing time stamps of the reference data samples to synchronize the CPE clock with the master clock.

Abstract: Systems and methods for monitoring impulse noise are described. At least one embodiment is a method, which comprises detecting whether impulse noise is present and in response to detecting the presence of impulse noise, performing time domain analysis to determine whether one or more impulse noise sources are present based on minimum interarrival time and maximum impulse length. The method further includes performing frequency domain analysis to estimate frequencies associated with the one or more impulse noise sources and based on the time domain analysis and frequency domain analysis, providing a total number of impulse noise sources and frequencies associated with the impulse noise sources. In this regard, the embodiments described herein provide dual-speed monitoring of impulse noise in the form of short-term and long-term monitoring.

Abstract: Systems and methods for monitoring impulse noise are described. At least one embodiment is a method, which comprises detecting whether impulse noise is present and in response to detecting the presence of impulse noise, performing time domain analysis to determine whether one or more impulse noise sources are present based on minimum interarrival time and maximum impulse length. The method further includes performing frequency domain analysis to estimate frequencies associated with the one or more impulse noise sources and based on the time domain analysis and frequency domain analysis, providing a total number of impulse noise sources and frequencies associated with the impulse noise sources. In this regard, the embodiments described herein provide dual-speed monitoring of impulse noise in the form of short-term and long-term monitoring.

Abstract: A system and method for ADSL USB bandwidth negotiation are presented. The system comprises a modem that is configured to transfer data between an ADSL line and a USB bus and that is further configured to receive an ADSL line rate setting, submit an isochronous bandwidth request to a computer, reduce the isochronous bandwidth request in response to the availability of isochronous bandwidth, modify the ADSL line rate setting in response to the availability of isochronous bandwidth, and modify the USB bus transfer mode in response to the availability of isochronous bandwidth. The method comprises steps of receiving an ADSL line rate setting, submitting an isochronous bandwidth request to a computer, reducing the isochronous bandwidth request in response to the availability of isochronous bandwidth, modifying the ADSL line rate setting in response to the availability of isochronous bandwidth, and modifying the USB bus transfer mode of the ADSL USB modem in response to the availability of isochronous bandwidth.

Abstract: A method for manufacturing an annular acoustic transducer array from a plate of transducer material, which enables production of precision aligned arrays at low cost. The circular plate is sawed along at least two lines that are radial to the axis of the plate. At steps along each radial cut, the plate is rotated first in one direction and then in an opposite direction by a predetermined angle such as slightly less than 90.degree.. The cuts result in the forming of several largely ring-shaped lands, each largely ring-shaped land being joined to the other rings of different radii by thin portions of the plate, and each ring being cut into segments. The bridges that join different rings, hold the transducer together until it can be mounted on a lens.

Abstract: An ultrasonic transducer for use in a high temperature environment and method for fabricating the same. A disk-shaped piezoelectric crystal is weakened in at least one surface in accordance with a predetermined line pattern relative to a first direction in that surface. The crystal is bonded to a thin lens material with a coefficient of thermal expansion dissimilar in this first direction. The predetermined line pattern is adapted to relieve stress in this first direction created by unequal rates of expansion or contraction of the crystal and the lens.

Abstract: An improved probe for in-service ultrasonic inspection of long lengths of a workpiece, such as small diameter tubing from the interior. The improved probe utilizes a conventional transducer or transducers configured to inspect the tubing for flaws and/or wall thickness variations. The probe utilizes a hydraulic technique, in place of the conventional mechanical guides or bushings, which allows the probe to move rectilinearly or rotationally while preventing cocking thereof in the tube and provides damping vibration of the probe. The probe thus has lower friction and higher inspection speed than presently known probes.

Abstract: A method for fabricating ferroelectric ultrasonic transducers by directing beam of electrons at a disk of ferroelectric material to produce a thin plate throughout which the Curie temperature is exceeded, and by applying a high DC Voltage across the faces of the disk while the Curie temperature is exceeded to polarize the thin plate.