摘要:
A system, method and apparatus are described that allow for the updating and transmittal of a low data rate signal providing ancillary network data as a rider on a high data rate optical signal. This subcarrier modulated signal can be processed and updated by using a drop/insert facility without having to alter the high data rate signal component of the data signal. Since the subcarrier signal can be detected by inexpensive equipment without having to detect and demultiplex the high data rate signal, the approach described offers a cost effective solution to the problem of network monitoring. Ancillary network management information can be communicated regardless of the quality or loss of the high data rate signal. In addition, by updating the subcarrier signal rider in a cumulative manner, a complete history of the fiber link the modulated optical signal travels on is provided to network management.
摘要:
An apparatus and method are applied to characterizing an dispersion-affecting element for use in controlling chromatic dispersion in an optical communications link. Information regarding the behavior of the dispersion-affecting element is recorded and stored in a medium that is provided for deployment with the dispersion-affecting element to enable improved management and active control of the dispersion-affecting element. The suitability of the dispersion-affecting element for operating under different conditions may also be characterized.
摘要:
A system includes a duct, a pressurized fluid source, and a valve. The duct receives one or more cables and the pressurized fluid source couples to a first end of the duct and produces fluid pressure within the duct. The valve couples to a second end of the duct and is closed for a time to build pressure within the duct, and then opened to permit the fluid under pressure within the duct to escape rapidly from the duct and propel the one or more cables through the duct.
摘要:
An optical communication system and method of use thereof which uses dispersion compensators to intentionally create a dispersive condition at the output of subsequent inline optical amplifiers. The present invention reduces four-wave mixing and increases the allowable spacing between optical amplifiers, thus reducing the required number of amplifiers and dispersion compensators for a given length of optical fiber. In one embodiment, dispersion compensators and optical amplifiers are alternately spaced from one another along a length of an optical fiber such that the dispersion compensators render a dispersive condition at the amplifiers allowing each amplifier to be run at a higher power level. In another embodiment, the dispersion compensator is collocated with the amplifier, but is positioned between a pre-amp stage and a high power output stage to overcompensate both the slope and absolute dispersion of the fiber up to that point. The dispersion compensator provides a dispersive condition at the output of the output stage allowing the amplifier to be operated at a higher power level without creating four-wave mixing. In yet another embodiment of the invention, an additional dispersion compensator is provided at the output of a transmitter to overcompensate both the slope and absolute dispersion of the fiber to render a substantially neutral dispersion signal upon arrival at the next optical line element or receiver.
摘要:
To verify the integrity of optical paths through and among optical switches, optical signals are provided with co-propagating supplemental signals. The supplemental signals preferably have at least one characteristic which allows distinguishing one supplemental signal from another. Associated with a port of a switch, means are provided for detecting a supplemental signal and determining if the supplemental signal indicates that a desired optical signal is passing through the port as expected and desired. Means for imparting or changing the distinguishing characteristic of a supplemental signal may also be employed to facilitate verifying the passage of optical signals.
摘要:
To verify the integrity of optical paths through and among optical switches, optical signals are provided with co-propagating supplemental signals. The supplemental signals preferably have at least one characteristic which allows distinguishing one supplemental signal from another. Associated with a port of a switch, means are provided for detecting a supplemental signal and determining if the supplemental signal indicates that a desired optical signal is passing through the port as expected and desired. Means for imparting or changing the distinguishing characteristic of a supplemental signal may also be employed to facilitate verifying the passage of optical signals.
摘要:
To verify the integrity of optical paths through and among optical switches, optical signals are provided with co-propagating supplemental signals. The supplemental signals preferably have at least one characteristic which allows distinguishing one supplemental signal from another. Associated with a port of a switch, means are provided for detecting a supplemental signal and determining if the supplemental signal indicates that a desired optical signal is passing through the port as expected and desired. Means for imparting or changing the distinguishing characteristic of a supplemental signal may also be employed to facilitate verifying the passage of optical signals.
摘要:
A rewind or fast forward operation may be performed in which a series of reduced-in-size images from previous frames in a video program may be presented to the viewer. In one implementation, a device may obtain sampled images corresponding to select frames of the video program and output a series of the sampled images in an order in which a sampling time corresponding to each of the sampled images in the video program monotonically increases or decreases in the output series. Differences in the sample times between successive images in the series of sampled images may not be uniform. The device may receive a selection of one of the images in the output series of sampled images and change a current output location of the video program to a location corresponding to the sampling time of the selected image.
摘要:
Disclosed is a computer audio interface adapted to enable blind or visually impaired users to locate icons positioned in rows in the background of a graphical user interface. Whenever the pointer of the interface is positioned on the background, the system produces a distinctive tone. Whenever the pointer is positioned in an icon row that is occupied by one or more icons, the system produces a distinctive chord. Whenever the pointer is positioned in the background and not in an occupied row, the system produces stereo effects that give the user information as to the relative left/right position of the pointer. Whenever the pointer is positioned in an occupied row, the amplitude of the left and right stereo channels is controlled such that whenever the pointer is to the left of the leftmost icon, substantially all of the volume is produced by the left speaker and whenever the pointer is to the right of the rightmost icon, substantially all of the the volume is produced by the right speaker. Whenever the pointer is located between the leftmost and rightmost icons, the volume is balanced substantially equally between the two speakers.
摘要:
It has been ascertained that there is a momentary drop in the flame-off arc voltage used to produce a ball in a ball bonder when the ball contacts the tool tip. A part of the present invention comprises a circuit for detecting this voltage drop and terminating the arc voltage immediately after such contact is made.