A communication network includes a coherent optics transmitter, a coherent optics receiver, an optical transport medium operably coupling the coherent optics transmitter to the coherent optics receiver, and a coherent optics interface. The coherent optics interface includes a lineside interface portion, a clientside interface portion, and a control interface portion.

An optical transmitter, having an encoder and modulator, transmits a data signal. The encoder maps information bits of the data signal to a symbol in eight-dimensional (8D) constellation space spanned by vectors IXT1, QXT1, IYT1, QYT1, IXT2, QXT2, IYT2, QYT2, wherein I and Q are in-phase and quadrature components of an optical carrier, X and Y are orthogonal polarizations of the optical carrier, and T1 and T2 are two consecutive transmission time slots, by selecting the symbol from a set of constellation points in the 8D space. The modulator uses the symbol in the two consecutive transmission time slots to modulate two carrier waves, and to transmit the two carrier waves over the orthogonal polarizations of the optical carrier. The set of constellation points do not include any constellation point with parallel Stokes vectors in the two consecutive transmission time slots but comprise constellation points with orthogonal Stokes vectors.

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.

A wireless optical transceiver, comprising: a light splitter for splitting light emitted from a light source into two lights; a data converter for dividing input data into a plurality of divided data in a symbol unit of a predetermined number of bits, and for converting values of a phase bit and a duty bit at a predetermined position in each of the divided data into a phase control signal and a blocking control signal; a modulator for polarization phase modulating two lights split according to the phase control signal, and for conveying or blocking two modulated polarized lights in response to the blocking control signal to modulate a pulse position; a polarized light combiner for generating a transmission optical signal by combining two polarized lights with a modulated polarization phase and a modulated pulse position; and a light amplifier for amplifying the transmission optical signal and transmitting it through a standby channel.

An optical wireless transmission device according to an embodiment of the present invention comprises: a modulation unit for receiving input of a first input signal and outputting a first output signal; and a light source control unit for controlling a first light source in accordance with the first output signal. The first output signal repeats “0” and “1” in a first phase during clock time if a binary value of the first input signal is 0, and repeats “0” and “1” in a phase opposite from the first phase during the clock time if a binary value of the first input signal is 1.

Disclosed are an optical signal communication method, and an optical signal transmission device and an optical signal reception device which perform the method. The optical signal communication method may comprise the steps of: receiving input data to be modulated into an optical signal, modulating the input data into the optical signal, and transmitting the optical signal to an optical signal reception device, wherein the optical signal includes a start pulse and an end pulse, and a time interval between the start pulse and the end pulse is determined on the basis of a data value of the input data.

This application discloses a signal generating method, apparatus, and system. One example method includes: performing cyclic electro-optic modulation on a first signal to generate a first optical frequency comb signal, where the first signal is a signal output by a laser source, the first optical frequency comb signal includes a target spectral component, and a frequency of the target spectral component is equal to a sum of or a difference between a frequency of the first signal and a frequency of a target signal; performing first filtering processing on the first optical frequency comb signal to generate the target spectral component; and generating the target signal based on a heterodyne beat frequency of the first signal and the target spectral component.

This application discloses a signal generating method, apparatus, and system. One example method includes: performing cyclic electro-optic modulation on a first signal to generate a first optical frequency comb signal, where the first signal is a signal output by a laser source, the first optical frequency comb signal includes a target spectral component, and a frequency of the target spectral component is equal to a sum of or a difference between a frequency of the first signal and a frequency of a target signal; performing first filtering processing on the first optical frequency comb signal to generate the target spectral component; and generating the target signal based on a heterodyne beat frequency of the first signal and the target spectral component.

An optical coherent transceiver includes a transmitter and a receiver that share laser light. The transmitter includes a pair of parent MZIs in a modulator, which are parent MZIs configured to perform quadrature modulation on the laser light according to a bias voltage, and two pairs of child MZIs in the modulator, which are child MZIs configured to perform phase modulation on the laser light according to the bias voltage. The transmitter includes a control circuit configured to control the bias voltage to be applied to the parent MZIs and the child MZIs. The control circuit is configured to, when turning light output of the transmitter off, with input of a data signal being set off, control the bias voltage such that a phase difference between the parent MZIs is around 90 degrees and a phase difference between the child MZIs in each of the pairs is 180 degrees.

An optical transmission device includes: a control module generate a control signal output which includes a slope adjust signal and a bias voltage offset adjust signal according to an input signal indicating a dispersion amount an electrical level adjust signal; a multi-level pulse amplitude modulator; and an asymmetrical optical modulator which is controlled by the slope adjust signal to be operated at one of a positive slope and a negative slope of a transfer function of the asymmetrical optical modulator itself, and is controlled by the bias voltage offset adjust signal of the control signal output to offset a bias voltage point of the asymmetrical optical modulator itself from a quadrature point of the transfer function, and modulates the multi-level pulse amplitude modulation signal to an optical signal to generate an optical modulate signal having a chirp.