An optical sensing system includes a transmitter side and a receiver side, and is configured to be positioned below a display of an electronic device. The transmitter side includes a light emitter. The receiver side includes an array of photodiodes. The light emitter of the transmitter side and the array of photodiodes of the receiver side are optically coupled via a waveguide. As a result of this construction, the optical sensing system can be operated as an interferometric optical sensor.

A method for establishing a data model and an apparatus, where a network element may create an optical signal group that includes optical signals with different wavelengths. After selecting a first optical signal group and obtaining first data of the first optical signal group, the network element may reflect, based on a first model established based on the first data of the first optical signal group, a noise coefficient and a gain that are obtained after an optical signal in the optical signal group of different wavelength combinations passes through the network element.

Aspects of the present disclosure describe distributed fiber optic sensing (DFOS) systems, methods, and structures that advantageously overcome problems encountered when operating DFOS systems over operational telecommunications facilities namely, cross-phase modulation, and uneven amplitude profiles through the use of a novel constant amplitude coded DFOS employing suppressed out-of-band signaling.

A method and an apparatus for self-calibration of an ONU receiver in a multi-wavelength PON system, said method including the initial physical layer scan of the receiver tuning range, distributed estimation of the down-stream wavelength channel drift with respect to the nominal standard-based wavelengths, and reporting the estimated downstream wavelength channel drift in the downstream Channel_Map message.

An optical reception apparatus (1) of the present invention includes: a local oscillator (11) outputting local oscillation light (22); an optical mixer (12) receiving a multiplexed optical signal (21) and the local oscillation light, and selectively outputting an optical signal (23) corresponding to the wavelength of the local oscillation light from the multiplexed optical signal; a photoelectric converter (13) converting the optical signal (23) output from the optical mixer into an electric signal (24); a variable gain amplifier (15) amplifying the electric signal (24) to generate an output signal (25) whose output amplitude is amplified to a certain level; a gain control signal generating circuit (16) generating a gain control signal (26) for controlling the gain of the variable gain amplifier (15); and a monitor signal generating unit (17) generating a monitor signal (27) corresponding to the power of the optical signal (23) using the gain control signal (26).

A receiving apparatus includes a first processor configured to compensate, in a perturbation back-propagation (PBP) scheme, waveform degradation of an optical signal by traveling an optical transmission line due to a nonlinear optical effect; a memory; and a second processor coupled to the memory and the second processor configured to change a gamma coefficient to be used in the PBP scheme, measure reception quality of the optical signal for each of gamma coefficients obtained by the changing, specify a gamma coefficient in accordance with the reception quality from among the gamma coefficients obtained by the changing, and set the specified gamma coefficient as a parameter of the PBP scheme.

A loss-based wavelength meter includes a first photodiode configured to measure power of monochromatic light; and a loss section having a monotonic wavelength dependency, wherein a wavelength of the monochromatic light is determined based on measurements of the first photodiode after the monochromatic light has gone through the loss section. This provides a compact implementation that may be used in integrated optics devices using silicon photonics as well as other embodiments.

There is provided a control device for controlling a first transmission device and a second transmission device, the control device including a memory, and a processor coupled to the memory and the processor configured to set a first wavelength path between the first transmission device and the second transmission device, select a monitoring wavelength path from established wavelength paths allocated on a transmission line between the first transmission device and the second transmission device, monitor a signal quality of the monitoring wavelength path, and increase power of the first wavelength path, based on the signal quality of the monitoring wavelength path.

A fiber optic assembly for supporting optical connections in a fiber optic network employing parallel optical configurations is described. In one embodiment, the fiber optic assembly includes at least two live multi-fiber components and at least one tap multi-fiber component. Optical signals are routed from one live multi-fiber component to another in a parallel optical connection configuration, with each group of optical signals corresponding to a respective group of fiber positions on each live multi-fiber component. Each group of optical signals is also routed to one of the first and second groups of fiber positions of the at least one tap multi-fiber component in a parallel optical connection configuration. In this manner, fiber optic signals can be simultaneously provided and monitored within an active fiber optic network using a parallel optical configuration without the need for interrupting network operations.

An optical transmission system includes a first optical transmission apparatus that adds a plurality of error correction codes to a main signal, retrieves, from a first error correction code that is added to the main signal and that corresponds to a first sub-carrier among the plurality of sub-carriers, a first code portion in excess of a predetermined redundancy level, distributes the first code portion to a second sub-carrier among the plurality of sub-carriers, concatenates a second code portion into the first error correction code, and transmits an optical signal including the main signal multiplexed with the first error correction code that has been concatenated with the second code portion.