An optical device may include an optical subassembly and a digital signal processor (DSP). The optical device may include a radio frequency (RF) interconnect that electrically connects the optical subassembly and the DSP. The optical device may include a passive RF filter on one or more transmission lines of the RF interconnect.

Apparatuses and methods for far-end monitoring of transmitter IQ skew in a DSCM system are described. Soft symbols for a given subchannel and a corresponding mirror subchannel are used as joint inputs to a MIMO equalizer. The hard decision symbols for the given subchannel and mirror subchannel are used as references to compute the equalizer coefficients. An estimated phase or estimated transmitter IQ skew is computed for at least the given subchannel using the equalizer coefficients. The computation is repeated to obtain estimated phase or estimated transmitter skew for all subchannels. The transmitter IQ skew is computed using the estimates from all subchannels. The computation is performed for each polarization. The computed transmitter IQ skew is communicated back to the transmitter via optical path (for correcting the skew).

An optical transmitter includes: a modulator, square law detector, and a processor. The modulator generates an optical signal indicating transmission data. The square law detector detects an intensity of the optical signal using a photodetector and output first intensity data indicating the detected intensity. The processor calculates, based on the transmission data, an electric field of the optical signal generated by the modulator by using parameters pertaining to a state of the modulator. The processor calculates second intensity data indicating the intensity of the optical signal based on the calculated electric field. The processor updates the parameters so as to reduce a difference between the first intensity data and the second intensity data. The processor controls the state of the modulator based on the parameters.

The present disclosure relates to the field of microwave and optoelectronic technologies, and in particular to an integrated microwave photon transceiving front-end for a phased array system, including: a ceramic substrate, on which a control integrated circuit, a silicon-based photonic integrated chip, a first amplifying chipset, a second amplifying chipset, and a microwave switch chipset are carried. The control integrated circuit is configured to control the silicon-based photonic integrated chip and the microwave switch chipset by means of an input control signal. The silicon-based photonic integrated chip is connected at one end with an input/output optical fiber, and at the other end with the first amplifying chipset and the second amplifying chipset. The two amplifying chipsets are connected to the microwave switch chipset respectively, and the microwave switch chipset is further connected with a phased array antenna.

An optical device may include an optical subassembly and a digital signal processor (DSP). The optical device may include a radio frequency (RF) interconnect that electrically connects the optical subassembly and the DSP. The optical device may include a passive RF filter on one or more transmission lines of the RF interconnect.

A transimpedance amplifier (TIA) device. The device includes a photodiode coupled to a differential TIA with a first and second TIA, which is followed by a Level Shifting/Differential Amplifier (LS/DA). The photodiode is coupled between a first and a second input terminal of the first and second TIAs, respectively. The LS/DA can be coupled to a first and second output terminal of the first and second TIAs, respectively. The TIA device includes a semiconductor substrate comprising a plurality of CMOS cells, which can be configured using 28 nm process technology to the first and second TIAs. Each of the CMOS cells can include a deep n-type well region. The second TIA can be configured using a plurality CMOS cells such that the second input terminal is operable at any positive voltage level with respect to an applied voltage to a deep n-well for each of the plurality of second CMOS cells.

The present disclosure is directed to a light-signal communication receiver device including a photo-receiving diode configured to generate a current signal on a first node from a received light signal, a preamplifier configured to convert the current signal on the first node into a voltage signal on a second node, and a differential amplifier including a first input connected to the first node and a second input connected to a third node coupled to the second node via an adjustment circuit. The adjustment circuit is configured to offset the level of the voltage signal of the second node, on the third node, in a controlled manner by a control signal.

A wavelength demultiplexer includes a photonic circuit and a control circuit that adjusts wavelength characteristics of the photonic circuit. The photonic circuit converts two orthogonal polarized waves contained in the incident light into two same polarized waves, which are supplied to a first optical demultiplexing circuit and a second optical demultiplexing circuit provided in the photonic circuit and having the same configuration. The photonic circuit supplies a total output power of monitor lights extracted from the same positions in the first optical demultiplexing circuit and the second optical demultiplexing circuit to the control circuit. The control circuit controls a first wavelength characteristic of the first optical demultiplexing circuit and a second wavelength characteristic of the second optical demultiplexing circuit based on the total output power of the monitor lights.

A wavelength conversion device includes: a memory; and a processor configured to: receive transmission signal light in which first wavelength division multiplexing signal light and second wavelength division multiplexing signal light that have different wavelength bands in which a plurality of rays of main signal light is wavelength-multiplexed are combined with supervisory control signal light that relates to supervisory control of the first wavelength division multiplexing signal light and the second wavelength division multiplexing signal light from a transmission line and that demultiplexes the supervisory control signal light from the transmission signal light; detect input power of the supervisory control signal light; demultiplexer each of the first wavelength division multiplexing signal light and the second wavelength division multiplexing signal light from the transmission signal light; convert at least one of the wavelength bands of the first wavelength division multiplexing signal light and the second wavelength division multiplexing signal light.

A method for signal reconstruction, the method may include obtaining, an input digital signal that is a digital representation of an received optical signal, wherein the received optical signal represents a transmitted optical signal that was transmitted by a coherent transmitter and over a channel to a coherent optical receiver; wherein a phase difference between the transmitted optical signal and the received optical signal is unknown; and generating a hybrid estimation, wherein the hybrid estimation represents a magnitude of the transmitted optical signal and a phase of the received optical signal.