Abstract: An optical amplifier. The amplifier includes a plurality of pump radiation sources, each pump radiation source adapted to produce radiation having a set of pump wavelengths and pump powers corresponding to the respective pump wavelengths, wherein at least one set is different from at least one other set. The amplifier also includes a plurality of pump radiation combiners and a coupler. The coupler is optically coupled to the outputs of the pump radiation combiners, receives the coupled radiation from the pump radiation combiners and outputs pump radiation profiles to respective coupler outputs. The amplifier also includes pump-signal combiners, each optically coupled to a respective coupler output of the coupler outputs, which are adapted to couple an optical signal with the respective pump radiation profiles.
Type:
Grant
Filed:
April 20, 2001
Date of Patent:
September 9, 2003
Assignee:
Dorsal Networks Inc.
Inventors:
William Shieh, Vladimir Petricevic, Thomas Clark
Abstract: A method and system for equalizing Q performance of a wideband, Raman-amplified optical communication system are disclosed. Wideband, Raman-amplifed systems suffer significant performance degradation from nonlinear effects in shorter wavelength channels. Absent compensation, the shorter wavelength channels limit system performance and restrict the amount of launch power that can be employed for the optical data signals in each wave division multiplexed channel. Careful design that employs increased channel spacing in the nonlinear region of the bandwidth can offset the increased nonlinear effects, thereby improving the worst channel's Q performance and permitting high launch power without unacceptable Q performance.
Type:
Grant
Filed:
July 30, 2001
Date of Patent:
September 2, 2003
Assignee:
Dorsal Networks, Inc.
Inventors:
M. Imran Hayee, William Shieh, Quan Zhen Wang
Abstract: A branch unit for a fiber optic system that includes a service path and a protection path, whereby the branch unit provides switching to account for problems due to fiber cuts and/or equipment failures that may occur in the fiber optic system. The service and protection paths meet at a branch point of the fiber optic network, or at a network protection equipment (NPE) that is located near a customer interface equipment. A plurality of switches are provided at the branch unit or NPE, along with a detector and a processor, to determine whether any signals are being received from the service path, and if not, to reconfigure the system to accept signals from the protection path.
Abstract: A collapsed ring fiber optic system includes a service path and a protection path provides at a shallow water portion of the fiber optic system, to deal with any fiber cuts that may occur at the shallow water portion without loss of main trunk bandwidth. The service and protection paths meet at a branch point, which is preferably located at a deep water portion of the fiber optic system. A passive combiner or a 1×2 switch is provided at the branch unit, along with a detector and a processor, to determine whether any signals are being received from the service path, and if not, to reconfigure the system to accept signals from the protection path. At another shallow water portion of the fiber optic system, nearby where a destination is located, the signal provided on the optical path over the deep water portion is split into a service path and a protection path, to provide redundancy to deal with any fiber cuts that may occur.
Type:
Grant
Filed:
May 8, 2001
Date of Patent:
April 29, 2003
Assignee:
Dorsal Networks, Inc.
Inventors:
Lee Daniel Feinberg, Bo Pedersen, Ronald Dale Esman, John Hagopian, Cathal Mahon, Brent Ashley Miller, M. Imran Hayee, Ronald E. Johnson, Nandakumar Ramanujam
Abstract: A method and system for generating both return-to-zero (RZ) and carrier suppressed return-to-zero (CSRZ) shaped signals using only a single optical modulator. The system includes: a switch for receiving a data signal and a clock signal as inputs, and outputting a voltage signal; a unit for controllably adjusting the phase of said clock signal before input to the switch; an optical modulator for receiving a continuous wave light (CW) signal and the voltage signal as inputs, and outputting one of an RZ and a CSRZ signal. To generate a CSRZ signal, the optical modulator is biased at a transmission minimum level signal. To generate an RZ signal, the optical modulator is biased at a transmission maximum level and the clock signal is phase shifted. Also disclosed is an optical communication transceiver including a plurality of optical modulator circuits generating both RZ and CSRZ signals.
Abstract: A method of modulating an optical signal is provided comprising the steps of providing a first electric field in a first optical signal path, providing a second electric field in a second optical signal path, transmitting an optical signal along the first optical signal path and the second optical signal path, amplitude modulating the optical signal via the first electric field and the second electric field, and phase modulating the optical signal via the first electric field and the second electric field. A clock source and a data source are ANDed to provide a data modulated RF signal on an offset waveguide electrode for generating the first and second electric fields. The magnitude of the electric field of the first electric field in the first optical signal path is greater than the magnitude of the electric field of the second electric field in the second optical signal path.
Abstract: An equipment rack includes a subrack mounted in a first direction and one or more circuit cards, each circuit card being mounted in the subrack in a second direction substantially perpendicular to the first direction and in parallel with each other circuit card mounted in the subrack. Each circuit card includes one or more ports coupled to a respective optical fiber traveling in the second direction. The equipment rack also includes a fiber handling track mounted in the first direction. The fiber handling track includes one or more radius control bosses, the number of radius control bosses equaling or exceeding the number of circuit cards mounted in the subrack. Each of the radius control bosses is adapted to receive an optical fiber coupled to a respective one of the one or more circuit cards and divert the received optical fiber from the second direction to the first direction.