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 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.

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.

An apparatus for generating a time-delayed product of two independent signals includes a fixed-wavelength laser. A first optical modulator is optically coupled to the fixed-wavelength laser and configured to modulate a fixed wavelength optical carrier with a first input signal of a set of input signals. The apparatus also includes a tunable laser. A second optical modulator is optically coupled to the tunable laser and configured to modulate a tunable optical carrier with a second input signal of the set of input signals. The apparatus also includes a dispersive element coupled to the second optical modulator, a first optical detector coupled to the dispersive element, a third optical modulator optically coupled to the first optical detector and the first optical modulator, an optical 90-degree hybrid element optically coupled to the third optical modulator, and a plurality of optical detectors optically coupled to the optical 90-degree hybrid element.

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.

An optical IQ modulator includes Y branching elements each of which has one input and two outputs and which are cascade-connected, QQPSK modulators each of which performs QPSK modulation on a corresponding one of continuous beams of light branched by the Y branching elements so that four signal points are present in a first quadrant on an IQ plane, Y combining elements each of which has two inputs and one output and which are cascade-connected, a phase modulator that modulates output light of the Y combining element in accordance with a drive signal Z, and a phase modulator that modulates output light of the phase modulator in accordance with a drive signal W.

A device and method related to processing an optical signal so as to compensate nonlinear distortions of optic fibers are provided. The method includes: generating a first signal by equalizing the optical signal using a first DBP algorithm; generate a first sequence of LLRs by demapping and deinterleaving the first signal; generating a first sequence of bits by iteratively decoding the first sequence of LLRs for a first number of iterations; generating a sequence of QAM symbols by mapping and interleaving the first sequence of bits; generating a second signal by equalizing the first signal based on the sequence of QAM symbols using a second DBP algorithm; generating a second sequence of LLRs by demapping and deinterleaving the second signal; and generating a second sequence of bits by iteratively decoding the second sequence of LLRs for a second number of iterations.

Deep neural networks (DNNs) have become very popular in many areas, especially classification and prediction. However, as the number of neurons in the DNN increases to solve more complex problems, the DNN becomes limited by the latency and power consumption of existing hardware. A scalable, ultra-low latency photonic tensor processor can compute DNN layer outputs in a single shot. The processor includes free-space optics that perform passive optical copying and distribution of an input vector and integrated optoelectronics that implement passive weighting and the nonlinearity. An example of this processor classified the MNIST handwritten digit dataset (with an accuracy of 94%, which is close to the 96% ground truth accuracy). The processor can be scaled to perform near-exascale computing before hitting its fundamental throughput limit, which is set by the maximum optical bandwidth before significant loss of classification accuracy (determined experimentally).

Arrangements for transmitting network credentials from a user device to a second device to enable the second device to connect to a network are disclosed. At the user device, a user inputs network credentials for the second device to enable the second device to connect to a network. The user device transmits modulated light to the second device. The light is modulated so that the transmitted light is encoded with the network credentials. The second device has a photo sensor for receiving the modulated light from the user device and a processor for processing the modulated light to obtain the network credentials from the received modulated light.