An optical add/drop device (100) comprising: a common port (102); an add port (106); a first wavelength selective optical filter (110) configured to: receive an optical signal at an add wavelength from the add port and transmit said optical signal at the add wavelength towards the common port; and receive optical signals from the common port and reflect optical signals not at the add wavelength; a second wavelength selective optical filter (114) configured to receive said optical signals from the common port reflected by the first wavelength selective optical filter and transmit an optical signal at a drop wavelength, different to the add wavelength; a drop port (116); and an optical waveguide (118) configured receive said optical signal at the drop wavelength transmitted by the second wavelength selective optical filter and route said optical signal to the drop port.

The invention relates to an optoelectronic transceiver device comprising a first optical connector (OC1) capable of connection to a first bidirectional optical fibre (OF1), and a second optical connector (OC2) capable of connection to a second bidirectional optical fibre (OF2), the device further comprising: an insertion-extraction module (ADM) capable of: extracting a wave-length (λ.sub.Rx) from a plurality of wavelengths constituting a first optical signal received by the first optical connector (OC1) and transmitting the first optical signal without the extracted wavelength to the second optical connector (OC2); inserting a wavelength (λ.sub.Tx) into a second optical signal received by the second optical connector (OC2) and transmitting the second optical signal with the inserted wavelength to the first optical connector (OC1); an electric-optical conversion module (EC1) capable of providing the insertion-extraction module with the wavelength (λ.sub.Tx) inserted into the second optical signal from an incoming electric signal (Data Tx); and an optical-electric conversion module (EC2) capable of converting the wavelength (λ.sub.Rx) extracted from the first optical signal by the insertion-extraction module into an outgoing electric signal (Data Rx).

An optical communications network comprises optical data links interconnected by add-drop nodes, the optical data links comprising data channels. The data channels are allocated into equal-sized bins. In response to a first data channel request between a given source-destination pair, one of the equal-sized bins is assigned to the data channel request. In response to requests for additional bandwidth for the same source-destination data channel request, unused channels within the assigned equal-sized bin are allocated to the data channel request. In response to subsequent data channel requests between different source-destination pairs, additional unallocated equal-sized bins are assigned to the subsequent data channel requests. In response to subsequent data channel requests when resource sharing for one equal-sized bin, data channels in the last equal-sized bin are assigned using the reverse channel assignment process. Reverse channel assignment can also be used for other bins as an option.

The present disclosure relates to the field of communications technologies, and in particular, to an optical add/drop multiplexer, such that the optical add/drop multiplexer can ensure proper processing of light in two directions. The optical add/drop multiplexer can complete an extraction of a signal in one direction using one microring resonant cavity and two optical circulators, and if a wavelength of a signal in the other direction is the same as a resonant wavelength of the microring resonant cavity, the signal may reenter an optical network after passing through two microring resonant cavities and one optical circulator, and is not affected. Therefore, proper processing of optical signals in the two directions is ensured, and the optical signals in the two directions do not interfere with each other.

An apparatus for management of a spectral capacity of a wavelength division multiplexing, WDM, system includes at least one pair of transmission fibers provided for transporting optical signals. Each transmission fiber of a transmission fiber pair is connected to a first port of an optical circulator having at least two additional ports and adapted to transmit an incoming optical signal entering one of its ports via its next port. WDM subsystems configured with counter-propagating assignable wavelengths are connected to associated ports of the optical circulator of the apparatus.

An optical add/drop device (100) comprising: a common port (102); an add port (106); a first wavelength selective optical filter (110) configured to: receive an optical signal at an add wavelength from the add port and transmit said optical signal at the add wavelength towards the common port; and receive optical signals from the common port and reflect optical signals not at the add wavelength; a second wavelength selective optical filter (114) configured to receive said optical signals from the common port reflected by the first wavelength selective optical filter and transmit an optical signal at a drop wavelength, different to the add wavelength; a drop port (116); and an optical waveguide (118) configured receive said optical signal at the drop wavelength transmitted by the second wavelength selective optical filter and route said optical signal to the drop port.

An apparatus includes a reconfigurable optical add/drop multiplexer (ROADM) having an input port to receive a first optical signal from a second device. The ROADM also includes a first wavelength selective switch (WSS), in optical communication with the input port, to convert the first optical signal into a second optical signal, a loopback, in optical communication with the first WSS, to transmit the second optical signal, and a second WSS, in optical communication with the loopback, to convert the second optical signal to a third optical signal and direct the third optical signal back to the second device via the input port.

An optical-communication module includes an arrayed waveguide grating; a light transmitter including light-emitting elements for emitting first signal beams into the arrayed waveguide grating, wherein the first signal beams are converged into one first communication beam in the arrayed waveguide grating; a wavelength division multiplexing filter is used to transmit the first communication beam emitted by the arrayed waveguide grating to an optical fiber; an optical receiver including optical sensor for sensing second signal beams emitted from the arrayed waveguide grating. The optical fiber is used for transmitting a second communication beam to the wavelength division multiplexing filter. The second communication light beam enters the arrayed waveguide grating through the wavelength division multiplexing filter. The second communication beam is divided into the second signal beams in the arrayed waveguide grating.

An optical transceiver of the present invention includes a coexistence element therein. An optical signal according to a first standard and an optical signal according to a second standard are transmitted and received through an optical cable accommodated in a first receptacle of the optical transceiver, and in the coexistence element, the optical signal according to the first standard and the optical signal according to the second standard are divided/combined. Among the divided upstream optical signals, the optical signal according to the first standard is photoelectrically converted in the optical transceiver, and the optical signal according to the second standard is transmitted to the outside through an optical cable accommodated in a second receptacle.

An optical circuit is used with continuous wave signals having different wavelengths at a channel spacing from one another. A portion of the optical circuit is implemented in a photonic integrated circuit. Modulators in a modulation stage modulate the continuous wave signals to produce modulated signals. A multiplexing stage, which can have multiplexing filters, power combiners, or power couplers, multiplexes the continuous wave or modulated signals to produce multiplexed signals. The multiplexing stage may be placed either before or after the modulation stage. One or more polarization rotator and combiner (PRC) devices in a final stage combines the multiplexed signals into an output signal. The output signal has a first set of the different wavelengths at a first polarization and has a second separate set of the different wavelengths at a second polarization orthogonal to the first polarization.