Systems and methods for optical modulation index calibration in a CATV network.

A system for delivering multiple passive optical network services is disclosed. The system includes a first optical transmission service comprising a common wavelength pair routed from a source to each of a plurality of subscribers. The system further includes a second optical transmission service comprising a plurality of unique wavelength pairs, where each of the unique wavelength pairs is routed from the source to a subscriber among the plurality of subscribers. The system delivers the first optical transmission service and the second optical transmission service to the subscriber on a single optical fiber.

An optical transceiver includes a wavelength-tunable transmission unit configured to transmit an optical transmission signal, a wavelength-tunable reception unit configured to receive an optical reception signal, a wavelength table configured to store a plurality of combinations of a transmission wavelength and a reception wavelength, an input terminal configured to input a wavelength selection signal, and a control unit configured to select one combination of the transmission wavelength and the reception wavelength from the wavelength table based on the wavelength selection signal, and perform transmission wavelength control for setting the selected transmission wavelength in the wavelength-tunable transmission unit as a wavelength of the optical transmission signal and reception wavelength control for setting the selected reception wavelength in the wavelength-tunable reception unit as a wavelength of the optical reception signal.

A carrier office includes an optical line terminal, a first transmit-erbium-doped fiber amplifier (EDFA), and a second transmit-EDFA. The OLT is configured to transmit first and second optical signals. The first transmit-EDFA is optically coupled to the OLT and a first feeder fiber, and the first feeder fiber is optically coupled to a first remote node (RN). The first transmit-EDFA is operable between a respective enabled state and a respective disabled state. The second transmit-EDFA is optically coupled to the OLT and a second feeder fiber, and the second feeder fiber is optically coupled to a second RN. The second transmit-EDFA is operable between a respective enabled state and a respective disabled state.

Systems and methods for optical modulation index calibration in a CATV network.

Optical fiber-based wireless systems and related components and methods are disclosed. The systems support radio frequency (RF) communications with clients over optical fiber, including Radio-over-Fiber (RoF) communications. The systems may be provided as part of an indoor distributed antenna system (IDAS) to provide wireless communication services to clients inside a building or other facility. The systems incorporate various functions, such as optical network terminal (ONT), splitter, and local powering, in antenna coverage areas.

A wavelength-selectable laser device providing spatially-selectable wavelength(s) may be used to select one or more wavelengths for lasing in a tunable transmitter or transceiver, for example, in a wavelength division multiplexed (WDM) optical system such as a WDM passive optical network (PON). The wavelength-selectable laser device uses a dispersive optical element, such as a diffraction grating, to disperse light emitted from a laser emitter and to direct different wavelengths of the light toward a reflector at different spatial positions such that the wavelengths may be selected by allowing light to be reflected from selected spatial position(s) back into the laser emitter. Thus, the reflected light with a wavelength at the selected spatial position(s) is allowed to complete the laser cavity.

In one embodiment, an optical line terminal judges whether the optical network unit operates at a correct uplink wavelength and a correct downlink wavelength during an optical network unit activation progress; and broadcasts a wavelength configuration message if the optical network unit does not operate at the correct uplink wavelength and the correct downlink wavelength to instruct the optical network unit to tune its uplink wavelength and downlink wavelength respectively to the correct uplink wavelength and the correct downlink wavelength.

Methods, systems, and devices for network communications to reduce optical beat interference (OBI) in upstream communications are described. For example, a fiber node may provide a narrow band seed source to injection lock upstream laser diodes. Therefore, upstream communications from each injection locked laser diode may primarily include the wavelength associated with each seed source. The seed sources may be unique to each end device and configured to minimize OBI. That is, the upstream laser diodes may be generic, but the received seed source may enable upstream communications at varying wavelengths. The fiber node may provide each seed source by filtering (e.g., by a grating filter) a broadband light source.

An OLT configures combinations of wavelength pairs used for upstream and downstream signals, in a wavelength multiplexing optical communication system which performs single-core bidirectional transmission of a plurality of upstream and downstream signals, in such a way that the maximum value of the chromatic dispersion delay amount calculated from each wavelength pair is less than the maximum value of the chromatic dispersion delay amounts calculated when the combinations of wavelength pairs used for upstream and downstream signals are both allocated from the short wave side.