A pluggable optical module according to the present invention includes a pluggable electric connector configured so as to be insertable into and removable from an optical transmission apparatus, and capable of transmitting/receiving a data signal to/from the optical transmission apparatus, a drive unit configured to output first/second driving signals by amplifying the data signal, an optical signal output unit configured to output a first/second optical signal modulated according to the first/second drive signal, a light-intensity monitoring unit configured to monitor intensities of the first/second optical signals, a control unit configured to control a gain of the drive unit so as to adjust a difference between the intensities of the first/second optical signals based on a result of the monitoring by the light-intensity monitoring unit, and a pluggable optical receptor configured so that an optical fiber can be inserted thereinto and removed therefrom, and configured to output the first/second optical signals.

An example system includes a hub transceiver and a plurality of edge transceivers. The hub transceiver is operable to transmit, over a first communications channel, a first message to each of the edge transceivers concurrently, including an indication of available network resources on an optical communications network. Each of the edge transceiver is operable to transmit, transmit, over a second communications channel, a respective second message to the hub transceiver including an indication of a respective subset of the available network resources selected by the edge transceiver for use in communicating over the optical communications network. Further, the edge transceiver is operable to receive, from the hub transceiver, a third message acknowledging receipt of a selection and a fourth message confirming an assignment of the selected subset of the available network resources to the edge transceiver.

A receiver system is provided for receiving a coherent Pulse Amplitude Modulation (PAM) encoded signal. The receiver system may include an optical polarization component configured to modulate a polarization of the received coherent PAM encoded signal. The receiver system may further include a digital signal processor (DSP) configured to perform polarization recovery between the received coherent PAM encoded signal and the LO signal using a first control loop, and to perform phase recovery between the received coherent PAM encoded signal and the LO signal using a second control loop.

A receiver system is provided for receiving a coherent Pulse Amplitude Modulation (PAM) encoded signal. The receiver system may include an optical polarization component configured to modulate a polarization of the received coherent PAM encoded signal. The receiver system may further include a digital signal processor (DSP) configured to perform polarization recovery between the received coherent PAM encoded signal and the LO signal using a first control loop, and to perform phase recovery between the received coherent PAM encoded signal and the LO signal using a second control loop.

A 2×2 optical multi-input-multi-output (MIMO) demultiplexer is disclosed. A first optical phase shifter applies a first relative phase shift between a first pair of optical transmission paths that are received from MIMO inputs, and a first 2×2 optical coupler combines the first pair of optical transmission paths and outputs a second pair of optical transmission paths. A second optical phase shifter applies a second relative phase shift between the second pair of optical transmission paths, and a second 2×2 optical coupler combines the second pair of optical transmission paths and outputs a third pair of optical transmission paths. A third optical phase shifter applies a third relative phase shift between the third pair of optical transmission paths, and a third 2×2 optical coupler combines the third pair of optical transmission paths and outputs a fourth pair of optical transmission paths, which are output by a pair of MIMO outputs.

A method and an apparatus for polarization multiplexing and encoding in a visible light communication system based on a gold nanoparticle are provided. A method for encoding in a receiver using a polarizing characteristic in a visible light communication system based on a gold nanoparticle, which is performed by a computer device, includes splitting a receive signal into left circular polarization light and right circular polarization light by allowing the receive signal to pass through a linear polarizer and estimating a phase retardation difference, and detecting a transmit symbol by estimating the phase retardation difference.

A method and an apparatus for polarization multiplexing and encoding in a visible light communication system based on a gold nanoparticle are provided. A method for encoding in a receiver using a polarizing characteristic in a visible light communication system based on a gold nanoparticle, which is performed by a computer device, includes splitting a receive signal into left circular polarization light and right circular polarization light by allowing the receive signal to pass through a linear polarizer and estimating a phase retardation difference, and detecting a transmit symbol by estimating the phase retardation difference.

[Problem] An optical receiver using a polarization demultiplexing technique is miniaturized.

[Solution] An optical receiver 100A for receiving a polarization multiplexed signal obtained by performing orthogonal polarization multiplexing on two optical signals. The optical receiver includes an IL 1 splitting the polarization multiplexed signal into two transmitted signals that are asymmetric in terms of a light transmission characteristic, O/Es 2a and 2b converting the transmitted signals resulting from the split into electrical signals, a downsampler 3 downsampling the electrical signals resulting from the conversion to generate low-speed digital signals, a calculator 4 calculating coefficients of a polarization separation matrix from the resultant low-speed digital signals, a level adjuster 5A adjusting, in accordance with the coefficients resulting from the calculation, signal levels of the electrical signals resulting from the conversion to generate a plurality of adjustment signals, adders 6Aa and 6Ab adding the generated adjustment signals to generate addition signals, and discriminators 7a and 7b restoring and extracting the two optical signals from the generated addition signals.

[Problem] An optical receiver using a polarization demultiplexing technique is miniaturized.

[Solution] An optical receiver 100A for receiving a polarization multiplexed signal obtained by performing orthogonal polarization multiplexing on two optical signals. The optical receiver includes an IL 1 splitting the polarization multiplexed signal into two transmitted signals that are asymmetric in terms of a light transmission characteristic, O/Es 2a and 2b converting the transmitted signals resulting from the split into electrical signals, a downsampler 3 downsampling the electrical signals resulting from the conversion to generate low-speed digital signals, a calculator 4 calculating coefficients of a polarization separation matrix from the resultant low-speed digital signals, a level adjuster 5A adjusting, in accordance with the coefficients resulting from the calculation, signal levels of the electrical signals resulting from the conversion to generate a plurality of adjustment signals, adders 6Aa and 6Ab adding the generated adjustment signals to generate addition signals, and discriminators 7a and 7b restoring and extracting the two optical signals from the generated addition signals.

A wireless system may include a central processor and an access point. The central processor may generate an optical signal on an optical fiber. The optical signal may include an optical local oscillator (LO) signal and one or more carriers. The central processor may modulate different combinations of transverse optical modes, orbital angular momentum, polarization, and/or carrier frequency of the optical signal to concurrently convey respective wireless data streams. The orthogonality of the transverse optical modes, orbital angular momentum, polarization, and carrier frequency may allow many wireless data streams to be modulated onto the optical signal and concurrently transmitted and propagated on the optical fiber independent of each other for transmission to one or more external devices.