Thermal tuning and quadrature control of opto-electronic devices using active extinction ratio tracking is proved by phase shifting, via a first phase shifter, a first optical signal carried on a first arm of an interferometer relative to a second optical signal carried on a second arm of the interferometer; combining the first optical signal with the second optical signal as an output signal; detecting a peak value in the output signal; and adjusting a relative phase offset imparted by the first phase shifter on the first optical signal relative to the second optical signal, based on the peak value, to increase an amplitude of the peak value. In various embodiments, the peak value is increased over time to maximize an extinction ratio of the optoelectronic device and maintain the extinction ratio in a maximized state during operation.

A system senses analytes through one or more sensors that detect or measure a physical characteristic. The one or more sensor generate a spectroscopic-data signal corresponding to the detection. An edge device communicatively couples the one or more sensors that communicatively couples a wide-area network coupling a cloud service. The edge device includes a data acquisition device that receives spectroscopic data signals from the one or more sensor and a processor that processes the spectroscopic-data signals to identify an analyte. The edge device also includes a transceiver that transmits data identifying the analytes to the cloud service.

A system for data transmission has a transmitter and a receiver connected by an optical channel. The transmitter has a transmitter laser and a transmitter-side electroabsorption modulator with an optical output. An electrical data input of the transmitter is connected to an electrical modulation terminal of the transmitter-side electroabsorption modulator. The receiver has a receiver laser and a receiver-side electroabsorption modulator with an optical output forming the input of the receiver. An electrical data output of the receiver is connected to the electrical modulation terminal of the receiver-side electroabsorption modulator. The transmitter and receiver lasers are detunable by specification of a physical variable, each provided by a respective control unit. The control units are synchronized and they specify the same signal at their outputs for establishing the physical variable for establishing the laser frequency.

Optical transceivers comprising optical loopback circuits are described. The optical transceiver may comprise a housing, which may host a transmitter, a receiver and the optical loopback circuit. The optical loopback circuit may be configured to route at least a portion of a modulated optical signal from the transmitter to the receiver. The optical loopback circuit may comprise tap couplers and/or optical switches. The optical transceiver may be switched between a normal mode and a calibration mode. The optical transceiver may maintain the same fiber connections even when the optical transceiver is switched from one mode to another. The transmitter, the receiver and the optical loopback circuit may be disposed on a common substrate, or on separate substrates.

In order to suppress any reduction in the reception performance of an optical transceiver, the optical transceiver includes a light source, an optical splitter that splits the output of the light source into a first split light and a second split light, an optical modulation unit that modulates the first split light, a coherent receiver that causes the inputted received light to interfere with the second split light, and a first control unit that controls the split ratio of the optical splitter on the basis of the reception characteristic of the received light received by the coherent receiver.

Apparatus and method for digital signal constellation transformation are provided herein. In certain configurations, an integrated circuit includes an analog front-end that converts an analog signal vector representing an optical signal into a digital signal vector, and a digital signal processing circuit that processes the digital signal vector to recover data from the optical signal. The digital signal processing circuit generates signal data representing a signal constellation of the digital signal vector. The digital signal processing circuit includes an adaptive gain equalizer that compensates the signal data for distortion of the signal constellation arising from biasing errors of optical modulators used to transmit the optical signal.

A packaged integrated white light source configured for illumination and communication or sensing comprises one or more laser diode devices. An output facet configured on the laser diode device outputs a laser beam of first electromagnetic radiation with a first peak wavelength. The first wavelength from the laser diode provides at least a first carrier channel for a data or sensing signal.

A smart light source configured for visible light communication. The light source includes a controller comprising a modem configured to receive a data signal and generate a driving current and a modulation signal based on the data signal. Additionally, the light source includes a light emitter configured as a pump-light device to receive the driving current for producing a directional electromagnetic radiation with a first peak wavelength in the ultra-violet or blue wavelength regime modulated to carry the data signal using the modulation signal. Further, the light source includes a pathway configured to direct the directional electromagnetic radiation and a wavelength converter optically coupled to the pathway to receive the directional electromagnetic radiation and to output a white-color spectrum. Furthermore, the light source includes a beam shaper configured to direct the white-color spectrum for illuminating a target of interest and transmitting the data signal.

A smart light source configured for visible light communication. The light source includes a controller comprising a modem configured to receive a data signal and generate a driving current and a modulation signal based on the data signal. Additionally, the light source includes a light emitter configured as a pump-light device to receive the driving current for producing a directional electromagnetic radiation with a first peak wavelength in the ultra-violet or blue wavelength regime modulated to carry the data signal using the modulation signal. Further, the light source includes a pathway configured to direct the directional electromagnetic radiation and a wavelength converter optically coupled to the pathway to receive the directional electromagnetic radiation and to output a white-color spectrum. Furthermore, the light source includes a beam shaper configured to direct the white-color spectrum for illuminating a target of interest and transmitting the data signal.

The present invention is directed to communication systems and methods. In a specific embodiment, the present invention provides an optical receiver that receives a data stream from an optical transmitter. The optical receiver determines a histogram contour parameter using the data stream and inserts the histogram contour parameter into a back-channel data segment, which is then transmitted to the optical transmitter. The optical transmitter changes its data transmission setting based on the histogram contour parameter. There are other embodiments as well.