A coherent passive optical network extender apparatus includes an extender transceiver for communication with an associated optical headend. The extender transceiver includes at least one receiving portion, at least one transmitting portion, and an extension processor. The apparatus further includes a signal adaptation unit configured to convert a downstream electrical transmission lane into a plurality of individual wavelengths. Each of the converted individual wavelengths are for transmission to one of an optical node and an end user. The apparatus further includes a plurality of transceivers, disposed within the signal adaptation unit, and configured to process and transmit the converted individual wavelengths as a bundle for retransmission to the respective end users.

An optical transceiver module having unibody structure is disclosed. The unibody structure comprises a single-piece substrate, an optical interface, and an optical engine. The components of the optical interface and the components of the optical engine are directly attached to the single-piece substrate.

A light amplification device according to an example aspect of the invention includes a wavelength demultiplexing unit configured to demultiplex the wavelength division multiplexed signal light into a plurality of wavelength bands; a plurality of light amplification media configured to amplify the plurality of pieces of demultiplexed multiplex signal light; a wavelength multiplexing unit configured to multiplex the amplified demultiplexed multiplex signal light; a plurality of excitation energy supply units configured to supply excitation energy to each of the plurality of light amplification media; and a control unit, wherein the control unit includes a wavelength multiplexing/demultiplexing control unit configured to control the wavelength demultiplexing unit and the wavelength multiplexing unit in such a way that a starting wavelength and a wavelength number become an optimum starting wavelength and an optimum wavelength number when a sum of power consumption of the plurality of excitation energy supply units is minimized.

A coherent passive optical network extender apparatus includes an extender transceiver for communication with an associated optical headend. The extender transceiver includes at least one receiving portion, at least one transmitting portion, and an extension processor. The apparatus further includes a signal adaptation unit configured to convert a downstream electrical transmission lane into a plurality of individual wavelengths. Each of the converted individual wavelengths are for transmission to one of an optical node and an end user. The apparatus further includes a plurality of transceivers, disposed within the signal adaptation unit, and configured to process and transmit the converted individual wavelengths as a bundle for retransmission to the respective end users.

In order to prevent a signal which a terminal station does not require from being intercepted by the terminal station without greatly changing the power of optical signals to be transmitted from a node to the terminal station, a node device is provided with: a first optical unit which outputs a first optical signal received from a first terminal station and addressed to a second terminal station, and a second optical signal received from the first terminal station, addressed to a third terminal station, and having a different wavelength band from the first optical signal; and a second optical unit to which the first and second optical signals outputted from the first optical unit are inputted, and which shifts the frequency of the first optical signal by a predetermined amount to create a fourth optical signal, passes the second optical signal without any change, couples the second and fourth optical signals, and transmits a resultant signal to the third terminal station.

An optical transceiver may include an optical transmitter and an optical receiver. The optical transmitter and receiver may each include a grid including one or more lanes spaced apart. Each lane may correspond to a predetermined optical signal, or wavelength. The optical transmitter may include one or more sets of lasers to output one or more optical signals corresponding to the grid. Each set of laser may output a set of optical signals. Each set of lasers and, therefore, each set of optical signals may have a different passband. For example, the multiplexing and/or demultiplexing architecture may have a wide passband for the first set of optical signals and a narrow passband for the second set of optical signals. The narrow passband may be determined based on the space between two wider passbands.

A method in an optical Wavelength Selective Switch, WSS, for multidirectional switching of optical signals. The optical WSS comprises a reflective element, a first tributary port and a second tributary port. The optical WSS switches (304) an optical signal between the first tributary port and the second tributary port with the reflective element.

This invention relates to provisioning wavelength-selective switches and reconfigurable optical add-drop multiplexers to minimize the bandwidth narrowing effect from the optical filters. Novel architectures and methods are disclosed that can significantly reduce bandwidth-narrowing on channels in a reconfigurable WDM network where a large number of optical filter elements are cascaded. Instead of blocking unused channels as in the prior art, unused channels are selectively provisioned depending on the state of their adjacent channels. Unused adjacent channels of an active channel are provisioned to follow the same path as the active channels. As each channels is deployed, the channel frequency is selected so as to minimize bandwidth narrowing.

An optical transceiver may include an optical transmitter and an optical receiver. The optical transmitter and receiver may each include a grid including one or more lanes spaced apart. Each lane may correspond to a predetermined optical signal, or wavelength. The optical transmitter may include one or more sets of lasers to output one or more optical signals corresponding to the grid. Each set of laser may output a set of optical signals. Each set of lasers and, therefore, each set of optical signals may have a different passband. For example, the multiplexing and/or demultiplexing architecture may have a wide passband for the first set of optical signals and a narrow passband for the second set of optical signals. The narrow passband may be determined based on the space between two wider passbands.

To use a plurality of wavelength bands, this seabed branching device comprises: a first demultiplexing unit that demultiplexes a wavelength multiplexed optical signal, which was input from a first terminal, into a first wavelength multiplexed optical signal and a second wavelength multiplexed optical signal; an optical add/drop unit that outputs at least a third wavelength multiplexed optical signal included in the first wavelength multiplexed optical signal to a second terminal station, and outputs at least a fifth wavelength multiplexed optical signal by multiplexing a fourth wavelength multiplexed optical signal included in the first wavelength multiplexed optical signal and a wavelength multiplexed optical signal input from the second terminal station; and a first multiplexing unit that multiplexes the second wavelength multiplexed optical signal and the fifth wavelength multiplexed optical signal, which was input from the optical add/drop unit, and outputs the result to a third terminal station.