The invention relates to a system for sending data in an optical network comprising source nodes (1-1, 1-2, 1-3, 1-4, 1-5), each capable of generating, in a spectral band that is associated with it, a multi-carrier optical data signal obtained by modulation of a source signal at a source wavelength and of sending this signal in the form of single-band data bursts (11-13, 21-23, 31-33, 41-43, 51-53) that can be associated with distinct source wavelengths, and a combiner (1,2) for combining single-band data bursts, sent by the source nodes in the spectral bands that are associated with them, into multi-band data bursts (61-63, 71-73) occupying a spectral band corresponding to a juxtaposition of the spectral bands associated with the source nodes. In this system, a unit for controlling an instant of sending of said single-band data bursts by the source nodes, implements a control plane taking account of a path time of the single-band data bursts sent by the source nodes to the combiner.

A photonic interconnect apparatus includes tunable light devices, multiplexers to multiplex optical signals produced by the tunable light devices onto optical paths, and a cyclic arrayed waveguide grating (AWG) to receive the optical signals over the optical paths, and to direct a given optical signal of the received optical signals to a selected output of a plurality of outputs of the cyclic AWG based on a wavelength of the given optical signal. A respective demultiplexer directs the given optical signal to a selected output of a plurality of outputs of the respective demultiplexer according to which coarse wavelength band the wavelength of the given optical signal is part of.

A system for performing failover switches in an optical network, such as a time and wavelength division passive optical networks (TWDM PON) like NG-PON2, includes a backup optical line terminal (OLT) for backing up communications of a primary OLT. The backup OLT is configured to allocate small upstream time slots, referred to herein as “de minimis” time slots, to at least one optical network terminal (ONT) communicating with the primary OLT during normal operation. When a failure occurs that prevents communication between the ONT and the primary OLT, the ONT autonomously tunes to the upstream and downstream wavelength pairs of the backup OLT and begins to transmit data to the backup OLT in the de minimis time slot allocated to it. The presence of data in the de minimis time slot indicates the occurrence of a failover switch to the backup OLT, and the backup OLT then begins to allocate time slots to this ONT, which is normally serviced by the primary OLT according to its normal TDM algorithm.

Disclosed are embodiments of an apparatus and method relating to an optical signal to noise ratio detection circuit, adopting an optical switch, a tunable optical filter, a photoelectric conversion module, a pilot-tone modulation signal conditioning module and a control module. After the photoelectric conversion module converts a to-be-detected optical signal to a voltage signal, the pilot-tone modulation signal conditioning module respectively amplifies an AC signal and a DC signal in the voltage signal, correspondingly converts the AC signal and the DC signal to two-way digital signals, determines a modulation depth of the pilot-tone modulation signal and a modulation depth of an ASE noise according to the two-way digital signals, and calculates an optical signal to noise ratio of the optical signal.

In one embodiment, an optical network system including a plurality of optical switches configured to switch beams of light which are modulated to carry information, a plurality of host computers comprising respective optical network interface controllers (NICs), optical fibers connecting the optical NICs and the optical switches forming an optically-switched communication network, over which optical circuit connections are established between pairs of the optical NICs over ones of the optical fibers via ones of the optical switches, the optically-switched communication network which including the optical NICs and the optical switches.

A device system for constituting a 3D image sensor based on optical phased array is provided. The device system includes an optical modulator that is integrated on the same photonic integrated circuit (PIC) chip as a laser diode array with different output wavelengths and a multiplexer for transmitting an optical wave having a wavelength selected from the laser diode array to an optical waveguide and modulates the optical wave into a specific optical signal, an optical phased array that radiates the optical signal received via an optical switch to the free space using a tunable transmit and receive (TRx) antenna array, and a photodetector that converts an Rx optical signal received by a Tx optical signal transmitted via the optical phased array into an electrical signal.

A monitoring control unit (22) of an OXC (20d) stores a management table (22a) in which pieces of information regarding a modulation mode, an FEC, and a frame mode of an optical signal are associated with each other, and sequentially changes the modulation mode, the FEC, and the frame mode according to the management table (22a) upon an LOS alert from a relay-side optical input/output unit (24) or an LOF alert from a DSP (25) being input thereto. Upon successfully receiving an appropriate optical signal according to the change, the monitoring control unit (22) acquires transmission source information included in the optical signal, and detects an occurrence of erroneous connection of an optical transmission line in an OXC (20g), which serves as a relay apparatus, when the acquired transmission source information indicates an optical cross-connect apparatus that is a transmission source different from an original transmission source.

A monitoring control unit (22) of an OXC (20d) stores a management table (22a) in which pieces of information regarding a modulation mode, an FEC, and a frame mode of an optical signal are associated with each other, and sequentially changes the modulation mode, the FEC, and the frame mode according to the management table (22a) upon an LOS alert from a relay-side optical input/output unit (24) or an LOF alert from a DSP (25) being input thereto. Upon successfully receiving an appropriate optical signal according to the change, the monitoring control unit (22) acquires transmission source information included in the optical signal, and detects an occurrence of erroneous connection of an optical transmission line in an OXC (20g), which serves as a relay apparatus, when the acquired transmission source information indicates an optical cross-connect apparatus that is a transmission source different from an original transmission source.

In a wavelength selective switch, an input port transmits an input beam, and diffraction grating disperses the input beam into optical channels. A liquid-crystal-on-silicon (LCoS) switch assembly has a phase grating profile and has addressable pixels, which are liquid crystal based. The LCoS switch assembly can selectively direct first-order diffracted beams of the optical channels for output to selected output ports. A tunable optical wedge adjacent the LCoS switch assembly can direct higher-order diffraction beams in the space between the output ports to reduce crosstalk. The wedge is a liquid crystal cell having spaced-apart resistive layers and having liquid crystal material disposed between the layers. In the wedge, the liquid crystal material can produce a phase profile in response to bias voltages applied to the resistive layers, and a beam steering angle of the phase profile can direct at least the second-order diffracted beams towards the port spacing between the ports.

Data center interconnections, which encompass WSCs as well as traditional data centers, have become both a bottleneck and a cost/power issue for cloud computing providers, cloud service providers and the users of the cloud generally. Fiber optic technologies already play critical roles in data center operations and will increasingly in the future. The goal is to move data as fast as possible with the lowest latency with the lowest cost and the smallest space consumption on the server blade and throughout the network. Accordingly, it would be beneficial for new fiber optic interconnection architectures to address the traditional hierarchal time-division multiplexed (TDM) routing and interconnection and provide reduced latency, increased flexibility, lower cost, lower power consumption, and provide interconnections exploiting N×M×D Gbps photonic interconnects wherein N channels are provided each carrying M wavelength division signals at D Gbps.