Abstract: An apparatus comprising a plurality of optical transmitters and a wavelength locker shared by the plurality of optical transmitters. A periodic transmission filter used for wavelength locker operations is in a network communication path and shapes optical transmissions from the plurality of optical transmitters to a network. An apparatus comprising at least one processor configured to receive a pre-filter signal corresponding to part of an optical signal comprising a pilot tone and to receive a post-filter signal corresponding to a part of the optical signal that passes through a period transmission filter, wherein a filtered part of the optical signal is directed into a network. The processor is also configured to perform wavelength locking based on a quadrature detection technique that aligns an adiabatic logical one position of a modulated transmission signal with a spectral transmission peak of the period transmission filter.

Abstract: According to one embodiment of a method for interference suppression in radio-over-fiber communication systems, the method uses a mode selection module to continuously update real time information of at least two mobile stations and determine to enter a cross mode or a single mode. In the single mode, when a mobile station approaches a switching point, a single mode command is issued to control at least one first specific remote antenna unit (RAU). In the cross mode, when an immediate cross condition is a new cross condition, a new cross mode table is generated, and when the position of any one mobile station of the at least two mobile stations cross a threshold, a cross mode command is issued to control at least one second specific RAU according to a corresponding cross mode table.

Abstract: A plurality of optical transmission sources provide data communication from a transmitting module to a common detector cooperative with a receiving module, the modules being subject to relative rotation about a shared axis. The detector can be located on the shared axis, each of the sources directing a beam onto the detector regardless of relative module orientation, and/or the light can be diffused, so that it is detected regardless of source and detector placement and relative module orientations. Transmissions can be distinguished according to synchronized timing, differing optical frequencies, differing baud rates, and/or differing circular polarizations. The detector can split the light into a plurality of beams which pass through different optical filters and are thereby distinguished. Cut-off circuits can prevent failed sources from transmitting. A diffused second light source and a second plurality of detectors can provide reverse communication from the receiving module to the transmitting module.

Abstract: A method of configuring a path between an ingress node and an egress node in an optical communications network, the path comprising a first hop and a subsequent hop. The method includes: a) selecting a candidate hop for the first hop of the path; b) obtaining a value of a signal feasibility parameter for the candidate hop; c) determining whether said value lies within an acceptable value range and if one is, accepting said candidate hop for the first hop of the path, and if one is not, repeating steps a. to c.; d) selecting a candidate hop for the subsequent hop of path; e) obtaining a value of a signal feasibility parameter for a combined path comprising the first hop and the candidate hop for the subsequent hop of the path; f) determining whether said value lies within an acceptable value range, if one is, acceptable value range accepting said candidate hop for the subsequent hop of the path, and if one is not, repeating steps d. and e.

Abstract: In order to realize a multiplexer/demultiplexer in which utilization efficiency of a frequency is high, wavelength characteristics of a transmission band is flat, the cost is low, the size is small, and a wavelength and a band are variable, the multiplexer/demultiplexer includes: first light branching means for branching inputted light into plurality of pieces of light and outputting the branched pieces of light; a plurality of light wavelength separating means for separating and outputting light outputted from the first light branching means for each of predetermined frequency bands; and an optical coupling means for making outputs having frequency bands different from each other among outputs from the light wavelength separating means gather and be outputted.

Abstract: An eye safety mechanism for use with a bi-directional data cable having an electrical interface at at least one (but potentially both) ends, despite the fact that the cable communicates over much of its length using a bi-directional optical channel. Upon power-up, the eye safety mechanism determines whether or not a loss of signal condition is present on an optical receive channel of the bi-directional data cable. If the loss of signal is present, the mechanism intermittently disables the optical transmit channel of the bi-directional data cable. On the other hand, if the loss of signal is not present, the mechanism enables the optical transmit channel of the bi-directional data cable without intermittently disabling transmission at least for most of the time until the next time a loss of signal is detected on the optical receive channel.

Abstract: Methods and systems for splitting an initiated signal are disclosed. An exemplary system may include a transmitter configured to selectively transmit an initiated signal, and a signal splitter in communication with the transmitter. The signal splitter may be configured to selectively split the initiated signal into a plurality of recipient signals for a plurality of recipient lines in communication with the transmitter. The signal splitter may be configured to selectively modify a number of recipient signals, e.g., by adjusting a spot size of the initiated signal on the signal splitter.

Abstract: A sending apparatus includes: a wavelength path multiplexing part; a sending wavelength path selection part; and an optical transmitter having optical sending parts. The wavelength path multiplexing part includes: sending wavelength path demultiplexing ports; and sending wavelength multiplexing ports connected thereto. The sending wavelength path multiplexing ports are connected to optical transmission paths respectively. The sending wavelength path selection part includes a wavelength multiplexing parts which multiplexing a set combination of optical signals among the optical signals inputted to the sending input ports and outputs it to any of the sending output ports. In the wavelength path sending or receiving by the wavelength path multiplexing/demultiplexing optical transmission apparatus, a non-selectable combination between a wavelength and a route can be avoided.

Abstract: In an optical transfer system, an optical transmission unit generates an optical signal in which respective polarization components are alternately present on a time axis, a time period during which the respective polarization components are simultaneously present on the time axis is substantially zero, and a symbol repetition cycle of optical signals of the respective polarization components becomes Ts, an optical reception unit causes an interference between local oscillation light and a received optical signal and converts an interfered optical signal to an electric signal, and a received electric-signal processing unit performs analog-digital conversion of an electric signal, elimination of a delay difference of Ts/2 between the respective polarized signal components, and adaptive equalization of a distortion other than the delay difference.

Abstract: A lighting node is described. One embodiment of the lighting node includes a lamp, a radio device, and a memory. The lamp is configured for generating illumination. The radio device is configured for radio communication. The radio device is configured to remotely receive a color profile from the controller. The lamp is also configured to generate illumination to substantially match the received color profile. The memory is configured to store a group identifier for the lighting node.

Abstract: In accordance with embodiments of the present disclosure, a method may include determining individual spectrum requirements for each of a plurality of signals to be communicated in an optical network, wherein a first signal of the plurality of signals has a first spectrum requirement and a second signal of the plurality of signals has a second spectrum requirement. The method may also include calculating a minimum spectrum granularity based on the individual spectrum requirements. The method may further include assigning each particular signal a channel spectrum equal to an integer multiple of the minimum spectrum granularity.

Abstract: A method and apparatus for determining if an optical input signals has been interrupted and responsively replacing an interrupted optical input signal with a replacement optical signal having a similar optical profile (e.g., such as a loopback between OADMs within a backbone network), thereby insuring that transient-induced high speed optical amplifier adjustments are avoided.

Abstract: A receiver chip, system and method for on-chip multi-node visible light communication, the receiver chip comprising: an array of receiver cells comprising an array of photodetectors, each receiver cell comprises at least one photodetector and is to receive light through the at least one photodetector, and a logical layer for independently configuring at least one selected receiver cell as a communication receiving channel. The system comprises an array of receiver cells comprising an array of photodetectors, each receiver cell includes at least one photodetector and is to receive light through the at least one photodetector, a logical layer to independently configure at least one selected receiver cell as a communication receiving channel, and a processor to receive data from the logical layer and control the logical layer for configuration of the receiver cells.

Abstract: The present invention provides systems and methods for a receiver threshold optimization loop to provide self-contained automatic adjustment in a compact module, such as a pluggable optical transceiver. The receiver threshold optimization loop utilizes a performance metric associated with the receiver, such as FEC, to optimize performance of the receiver. The receiver is optimized through a change in the receiver threshold responsive to the performance metric. Advantageously, the present invention provides improved receiver performance through a continuous adjustment that is self-contained within the receiver, such as within a pluggable optical transceiver compliant to a multi-source agreement (MSA). The receiver threshold optimization loop can include a fine and a coarse sweep of adjustment from an initial setting.

Abstract: An optical network and method of protection switching between first and second transceivers where dispersion compensation is effected electrically in the transmitters. The method includes detecting, at the second transceiver, a signal failure of a signal transmitted from the first transceiver and, upon detecting the signal failure, signaling the first transceiver to change its compensation function. The signaling can be done by encoding overhead bits in a signal transmitted from the second to the first transceiver. Another method of protection switching includes both transceivers toggling alternate reception paths upon detecting a signal failure and changing their dispersion compensation function to that of their respective alternate path.

Abstract: An apparatus and method for deriving fiber characteristics between two nodes in an optical communication network are disclosed. A roundtrip time for a signal to travel between two nodes is measured by sending the signal via the optical supervisory channel from a first node to a second node, which is configured for loopback operation. Fiber characteristics can be calculated based on the measured roundtrip time.

Abstract: A bit error generating device includes a light source, an input device, and a control processor. The control processor includes logic configured to: receive protocol or bitrate information regarding a live traffic signal via the input device; determine bit error simulation signal parameters based on the received protocol or bitrate information; configure the light source to generate the bit error simulation signal based on the bit error simulation signal parameters; and instruct the light source to inject the bit error simulation signal into an optical fiber carrying the live traffic signal.

Abstract: A multi-channel optoelectronic device is configured to establish a redundant status link with a remote device. The optoelectronic device can transmit N transmit optical signals to the remote device over a plurality of transmit channels and receive N receive optical signals from the remote device over a plurality of receive channels. The optoelectronic device includes one or more spare transmit and receive channels. When used with a remote device having spare transmit and receive channels, each device can establish a status link with the other and use the status link to switch out transmit and/or receive channels to identify and permanently switch out the worst transmit and/or receive channels. Alternately, the device can interoperate with a non-status-link enabled remote device by determining that the remote device is not status-link enabled, transitioning to a low transmit power mode, and transmitting and receiving over a plurality of default transmit and receive channels.

Abstract: A number of carriers are selected according to a modulation format and symbol rate to realize a superchannel having fixed capacity, for example. At a receive node, the superchannel is optically demultiplexed from a plurality of other superchannels. The plurality of carriers are then supplied to a photodetector circuit, which receives additional light at one of the optical signal carrier wavelengths from a local oscillator laser. An analog-to-digital converter (ADC) is provided in the receive node to convert the electrical signals output from the photodetector into digital form. The output from the ADC is then filtered in the electrical domain, such that optical demultiplexing of the carriers is unnecessary.

Abstract: An apparatus and method for extracting an optical clock signal are provided. The apparatus includes a first reflection filter selecting and reflecting only a first frequency component in an input optical signal; a first Fabry-Perot laser diode matching the first frequency component reflected by the first reflection filter with a predetermined output mode and outputting the first frequency component in the predetermined output mode; a second Fabry-Perot laser diode selecting a second frequency component in an input optical signal that has not been reflected but has been transmitted by the first reflection filter, matching the second frequency component with a predetermined output mode, and outputting the second frequency component in the predetermined output mode; and a photodetector receiving the first frequency component from the first Fabry-Perot laser diode and the second frequency component from the second Fabry-Perot laser diode and beating them to extract a clock signal.