Abstract: Optical transmission systems of the present invention include a plurality of optical amplifiers configured to provide optical amplification of one or more information carrying optical signal wavelengths. At least two of the optical amplifier are operated to provide net losses or net gains along corresponding spans, while the cumulative gain provided by the plurality of optical amplifiers substantially compensates for the cumulative loss of the spans.

Abstract: Optical systems of the present invention generally include an optical signal controller disposed along an optical link between two optical nodes. The optical signal controller is configured to provide a monitoring signal from an optical signal passing between the nodes as a plurality of wavelength sub-bands at least one of which includes a plurality of signal channels. The controller generates a compensating channel having an optical power that is a function of the monitoring signal power in the plurality of wavelength sub-bands or total power. The compensating channel is combined with the optical signal to compensate for power variations in the optical signal passing between the nodes. In addition, the compensating channels can be used to transmit communication or system supervisory information between monitoring points and/or nodes in the system.

Abstract: Optical transmission systems of the present invention include at least one optical amplifier configured to provide optical amplification of one or more information carrying optical signal wavelengths. At least one optical amplifier is controlled based on an in situ performance characterization of the at least one optical amplifier and the transmission fiber. The in situ, or installed, performance characteristics of the optical amplifier can be characterized based on relative gain measurements over the signal wavelength range as a function of the supplied pump power. The installed characterization allows the optical amplifier performance and gain profiles to be tightly controlled over the signal wavelength range in the transmission system.

Abstract: Optical transmission systems of the present invention include at least one optical amplifier configured to provide optical amplification of one or more information carrying optical signal wavelengths. At least one optical amplifier is controlled based on an in situ performance characterization of the at least one optical amplifier and the transmission fiber. The in situ, or installed, performance characteristics of the optical amplifier can be characterized based on relative gain measurements over the signal wavelength range as a function of the supplied pump power. The installed characterization allows the optical amplifier performance and gain profiles to be tightly controlled over the signal wavelength range in the transmission system.

Abstract: Optical systems of the present invention generally include an optical signal controller disposed along an optical link between two optical nodes. The optical signal controller is configured to provide a monitoring signal from an optical signal passing between the nodes as a plurality of wavelength sub-bands at least one of which includes a plurality of signal channels. The controller generates a compensating channel having an optical power that is a function of the monitoring signal power in the plurality of wavelength sub-bands or total power. The compensating channel is combined with the optical signal to compensate for power variations in the optical signal passing between the nodes. In addition, the compensating channels can be used to transmit communication or system supervisory information between monitoring points and/or nodes in the system.

Abstract: Optical systems of the present invention include an add/drop device and/or cross-connect device, which is reconfigurable to add and drop signal wavelengths between one or more transmission paths. The add/drop device includes a first selective element configurable to pass a first group of signal wavelengths including at least a first signal wavelength from an input path to a first add/drop path and pass continuing signal wavelengths differing from the first group of signal wavelength to a second add/drop path. A second selective element is provided that is configurable to pass a second group of signal wavelengths including at least a second signal wavelength from said first add/drop path and continuing signal wavelengths differing from the second group of wavelengths from said second add/drop path to an output path.

Abstract: Optical systems of the present invention include a plurality of optical processing nodes in optical communication via a plurality of signal varying devices. A first signal varying device includes an optical fiber configured to produce Raman scattering/gain in a signal wavelength range and a first signal variation profile. A first pump source is configured provides sufficient pump power in a plurality of first pump wavelengths to stimulate Raman scattering/gain in the optical fiber within the signal wavelength range.

Abstract: Optical systems, device, and methods including signal varying devices, such as optical amplifiers, attenuators, and filters that have controllable gain, loss and transparent intensity profiles, and which can include and be responsive to one or more local and remote controllers.

Abstract: Apparatuses, methods, and systems are disclosed that provide for simultaneously upconverting electrical signals carrying information at electric frequencies onto optical subcarrier lightwave frequencies that are greater and less than the carrier frequency of the lightwave onto which the electrical frequencies were upconverted. The upconversion of the electrical signals can be performed with or without suppression of the optical carrier frequency.

Abstract: Optical systems of the present invention include amplifiers configured to achieve maximum signal channel in a span downstream of the transmitter and amplifier site and to decrease the interaction between the wavelengths at high signal channel powers. In addition, the system can include various types of optical fiber positioned in the network to provide for increased signal channel powers and higher gain efficiencies in the system.

Abstract: Optical systems of the present invention include a plurality of optical processing nodes in optical communication via at least one signal varying device. The signal varying devices includes an optical fiber suitable for facilitating Raman scattering/gain in a signal wavelength range and a pump energy source for providing pump energy in a plurality of pump wavelengths. The pump source provides sufficient pump energy in each pump wavelength to stimulate Raman scattering/gain in the optical fiber within the signal wavelength range. The pump wavelengths are selected such that the combined Raman gain resulting from the pump energy supplied by each pump wavelength produces a desired signal variation profile in the signal wavelength range. In addition, the pump energy supplied by at least one of the pump wavelengths can be varied to produce a controlled signal intensity variation profile over the signal wavelength range in the optical fiber.

Abstract: Optical systems of the present invention include amplifiers configured to achieve maximum signal channel in a span downstream of the transmitter and amplifier site and to decrease the interaction between the wavelengths at high signal channel powers. In addition, the system can include various types of optical fiber positioned in the network to provide for increased signal channel powers and higher gain efficiencies in the system.

Abstract: Optical systems of the present invention include a plurality of optical processing nodes in optical communication via at least one signal varying device. The signal varying devices includes an optical fiber suitable for facilitating Raman scattering/gain in a signal wavelength range and a pump energy source for providing pump energy in a plurality of pump wavelengths. The pump source provides sufficient pump energy in each pump wavelength to stimulate Raman scattering/gain in the optical fiber within the signal wavelength range. The pump wavelengths are selected such that the combined Raman gain resulting from the pump energy supplied by each pump wavelength produces a desired signal variation profile in the signal wavelength range. In addition, the pump energy supplied by at least one of the pump wavelengths can be varied to produce a controlled signal intensity variation profile over the signal wavelength range in the optical fiber.

Abstract: Optical transmission systems of the present invention include at least one optical amplifier generally including an optical signal amplifying medium supplied with pump power in the form of optical energy in via an optical pump source. The pump source includes multiple optical sources, at least two of which provide optical energy in first and second wavelength ranges separated by a frequency difference. The amplifier includes a wavelength controller configured to adjust the wavelength range of at least one of the optical sources to vary the frequency difference in a manner sufficient to vary optical intensity noise produced when the optical energy from the multiple optical sources is combined.

Abstract: Optical systems of the present invention include a plurality of optical processing nodes in optical communication via at least one signal varying device. The signal varying devices includes an optical fiber suitable for facilitating Raman scattering/gain in a signal wavelength range and a pump energy source for providing pump energy in a plurality of pump wavelengths. The pump source provides sufficient pump energy in each pump wavelength to stimulate Raman scattering/gain in the optical fiber within the signal wavelength range. The pump wavelengths are selected such that the combined Raman gain resulting from the pump energy supplied by each pump wavelength produces a desired signal variation profile in the signal wavelength range. In addition, the pump energy supplied by at least one of the pump wavelengths can be varied to produce a controlled signal intensity variation profile over the signal wavelength range in the optical fiber.

Abstract: Apparatuses and methods are disclosed for operation of optical transmission systems. An optical transmission system of the present invention includes at least one signal varying device positioned to vary an optical signal passing to an optical processing node to achieve one or more desired signal characteristic in the optical signal as it approaches or reach the optical processing node. A controller is provided and configured to control the at least one signal varying device in response to at least one detected characteristic of said optical signal as it passes to the optical processing nodes. The signal varying devices are controlled collectively, in groups, or individually to achieve the desired characteristics in the optical signal when the optical signal arrives at the optical processing nodes. The processing nodes include optical transmitter in optical communication with optical receivers via signal varying devices, which include amplifiers, attenuators, filters, and other signal varying devices.

Abstract: Optical systems of the present invention include a plurality of optical processing nodes in optical communication via at least one signal varying device. The signal varying devices includes an optical fiber suitable for facilitating Raman scattering/gain in a signal wavelength range and a pump energy source for providing pump energy in a plurality of pump wavelengths. The pump source provides sufficient pump energy in each pump wavelength to stimulate Raman scattering/gain in the optical fiber within the signal wavelength range. The pump wavelengths are selected such that the combined Raman gain resulting from the pump energy supplied by each pump wavelength produces a desired signal variation profile in the signal wavelength range. In addition, the pump energy supplied by at least one of the pump wavelengths can be varied to produce a controlled signal intensity variation profile over the signal wavelength range in the optical fiber.

Abstract: A frequency synthesizer phase locked loop includes a voltage controlled oscillator (VCO) providing a variable frequency signal, a reference frequency oscillator providing a reference frequency signal, a phase comparison circuit for comparing the phases of the variable frequency and reference frequency signals and providing an output signal to a loop filter, the output of the loop filter providing a frequency control signal to the VCO. The phase comparison circuit includes a digital phase detector providing an output signal on an output line coupled to a charge pump for providing a first output signal to the loop filter; and an analog phase detector including a sample and hold circuit, and a control circuit responsive to the variable and reference frequency signals for providing a signal for sampling to the sample and hold circuit, the sample and hold circuit providing a second output signal to the loop filter.