Abstract: A method can be for use in a photonic analog to digital converter, a first optical signal and a radio frequency signal. The method modulates the first optical signal based on the radio frequency signal, quantizes one or more of phase, quadrature, and amplitude coordinates of the modulated signal, and provides the quantized coordinates to one or more electronic analog to digital converters.

Abstract: The present invention is an optical system configured for enabling co-transmission (ex.—co-propagation) of a reference signal and a carrier signal (ex.—or a phase encoded signal and a reference signal) in a same fiber. Since it is configured for enabling said co-transmission, the optical system of the present invention promotes reduced transmission microphonic sensitivity in the optical system.

Abstract: A photonic analog to digital converter includes one or more modulators configured to receive a first optical signal and a radio frequency signal. The one or more modulators is configured to modulate the first optical signal based on the radio frequency signal. The converter also includes circuitry configured to independently quantize one or more of phase, quadrature, and amplitude coordinates of the modulated signal. The circuitry provides the quantized coordinates to one or more electronic analog to digital converters.

Abstract: The present invention is a fiber optic data network, such as a passive optical network (PON), which includes a primary sub-network and a secondary sub-network. The primary sub-network may include a primary optical line terminal communicatively coupled to a plurality of primary optical network units. The secondary sub-network may include a secondary optical line terminal communicatively coupled to a plurality of secondary optical network units and to an intermediate optical network unit. The secondary sub-network may be communicatively coupled to the primary sub-network via the intermediate optical network unit, thereby allowing the PON to be configured so that the primary optical line terminal and the secondary optical line terminal are cascaded.

Abstract: Apparatuses, systems, and methods are disclosed that provide for an agile coherent optical modem that can generate agile RF waveforms and data rates on a generic opto-electronic hardware platform. An “agile coherent optical modem” [ACOM] approach to optical communications by employing a software configurable and adaptive technologies to the transport system. The ACOM generate agile RF waveforms and data rates on a generic opto-electronic hardware platform. By employing advanced communication techniques to the optical domain such as wavelength agility, waveform agility, and symbol rate agility, it is possible to enable robust optical communications. The ACOM allows for the transport capacity of a communications link to be varied, thereby accommodating variations in transport conditions, range, opacity, etc.

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: A monitoring device in an analog-to-digital converter, the monitoring device including a monitoring module configured to receive a first radio frequency signal provided by a first radio frequency modulator and a second radio frequency signal provided by a second radio frequency modulator. The first radio frequency signal being associated with a laser data and a radio frequency input signal. The laser data being associated with a radio frequency oscillator signal. The second radio frequency signal being associated with the laser signal and the radio frequency oscillator signal. The monitoring module is configured to determine a modification factor based on the first radio frequency signal and the second radio frequency signal.

Abstract: The present invention is a remote input analog-to-digital conversion (ADC) system. The system may generate low jitter, short duration optical pulses to allow for high performance sampling of an antenna signal at a remote end of the system. The system may utilize phase modulation and IQ demodulation (with a reference optical pulse stream) using separate analog-to-digital converters for I and Q to overcome linearity limitations. Low sampling rate analog-to-digital converters may be utilized by the system by using parallel, low optical pulse repetition rate paths and/or optical demultiplexer switching trees. The system is an optical fiber system.

Abstract: Apparatuses, systems, and methods are disclosed that provide for an agile coherent optical modem that can generate agile RF waveforms and data rates on a generic opto-electronic hardware platform. An “agile coherent optical modem” [ACOM] approach to optical communications by employing a software configurable and adaptive technologies to the transport system. The ACOM generate agile RF waveforms and data rates on a generic opto-electronic hardware platform. By employing advanced communication techniques to the optical domain such as wavelength agility, waveform agility, and symbol rate agility, it is possible to enable robust optical communications. The ACOM allows for the transport capacity of a communications link to be varied, thereby accommodating variations in transport conditions, range, opacity, etc.

Abstract: A method and apparatus for estimating fiber dispersion in an optical communication system including transmitting an optical signal carrying a unique word along an optical communication path, receiving the optical signal carrying the unique word from the optical communication path, producing an electrical signal corresponding to the received unique word, and processing the electrical signal corresponding to the received unique word to produce an estimate of the fiber dispersion in the optical communication system.

Abstract: A method of receiving optical channels including providing an optical band filter configured to filter at least one optical channel from a multiple channel optical signal and provide a band filtered optical signal. A periodic filter is configured to filter and/or shape one channel from the band filtered optical signal and provide the periodic filtered, shaped signal to a receiver and other optical system. The invention also relates to corresponding systems and apparatuses.

Abstract: A method of transmitting an optical communications signal, comprising receiving a first signal, encoding the signal with a differential or duobinary encoding scheme, encoding the signal with an oscillating signal component, and sub-carrier modulating the signal onto a sub-carrier of an optical carrier signal. The invention also relates to corresponding systems and apparatuses.

Abstract: Systems, apparatuses, and methods for producing and utilizing orthogonal optical data signals, which can be produced by modulating electrical data signals onto orthogonal polarization components of an optical carrier traveling in opposite directions in a common modulator. The modulator can include one or more traveling wave electrodes having first and second ends with a first electrical data input connected to the first end and a second electrical data input connected to the second end.

Abstract: Systems, apparatuses, and methods for producing and utilizing orthogonal optical data signals, which can be produced by modulating electrical data signals onto orthogonal polarization components of an optical carrier traveling in opposite directions in a common modulator. The modulator can include one or more traveling wave electrodes having first and second ends with a first electrical data input connected to the first end and a second electrical data input connected to the second end.

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 an electrical signal distortion compensator configured to electrically distort an electrical signal to offset optical distortion imposed by a Fabry-Perot filter on an optical signal corresponding to the electrical signal. The electrical signal distortion compensator can be used in an optical transmitter to distort the electrical signal prior to optical transmission, or in an optical receiver after optical transmission. The distortion compensation can be performed on a baseband signal or a modulated electrical carrier. Likewise, the distortion compensator can be deployed in combination with an optical receiver, which allows the use of the F-P filter-optical receiver combination with transmitters and receivers that do not include F-P filters or distortion compensators.

Abstract: An optical transmission system including at least one optical transmitter configured to transmit at least one signal wavelength and a tuning wavelength, an optical receiver including an optical filter having a filter bandwidth including the at least one signal wavelength and a percentage of the tuning wavelength and an optical to electrical signal converter configured to receive the at least one signal wavelength from said filter, a first tuning optical to electrical converter configured to receive a first portion of the tuning wavelength stopped by said filter, a second tuning optical to electrical converter configured to receive a second portion of the tuning wavelength passed by said filter, and a filter controller configured to tune the filter bandwidth based on the relative proportion of first and second portions of the tuning wavelength provided to the first and second tuning optical to electrical converters.

Abstract: Apparatuses, methods, and systems are disclosed for controlling optical signal wavelength spacing by providing for simultaneous upconversion of a plurality of electrical signal on subcarrier frequencies of an optical carrier frequency with or without modulation of an electrical data signal onto the optical carrier frequency. The optical carrier lightwave is split into a plurality of split lightwaves upon which one or more electrical frequencies carrying information can be upconverted onto optical subcarriers of the lightwave carrier frequency. The relative spacings of the optical subcarrier lightwaves will thus be unaffected by variation in the carrier frequency. The optical subcarrier lightwaves can then be recombined to form the optical data signal carrying the plurality of information carried by the electrical frequencies.

Abstract: Apparatuses, methods, and systems are disclosed for controlling optical signal wavelength spacing by providing for simultaneous upconversion of a plurality of electrical signal on subcarrier frequencies of an optical carrier frequency with or without modulation of an electrical data signal onto the optical carrier frequency. The optical carrier lightwave is split into a plurality of split lightwaves upon which one or more electrical frequencies carrying information can be upconverted onto optical subcarriers of the lightwave carrier frequency. The relative spacings of the optical subcarrier lightwaves will thus be unaffected by variation in the carrier frequency. The optical subcarrier lightwaves can then be recombined to form the optical data signal carrying the plurality of information carried by the electrical frequencies.

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.