Abstract: Real-time location system and method, the system including a tag and a plurality of groups, each group including: a plurality of battery operated secondary technology base-stations, and a battery operated wireless timing beacon generator to provide a timing beacon to the group, such that the timing beacon generator for a group obtains timing information for the timing beacon wirelessly from a timing server, and such that each timing beacon generator transmits timing beacons with timing information to the plurality of base-stations in the group, and each secondary technology base-station transmits a secondary technology signal to the tag based on the received timing beacon.

Abstract: Disclosed are methods, systems, devices, apparatus, computer-/processor-readable media, and other implementations, including a method, at a processor-based mobile device, that includes determining a first set of candidate positions of the mobile device corresponding to a first time instance based, at least in part, on position data including a first set of identifiers decoded from signals including respective first one or more light-based communications received by the mobile device from a first one or more light devices, with the mobile device being located at a first location at the first time instance. The method further includes selecting at least one candidate position from the first set of candidate positions, in response to a determination that the first set of candidate positions includes more than one candidate position, in order to resolve positional ambiguity, based, at least partly, on further position data from further signals from one or more devices.

Abstract: An optical network system includes an optical line terminal, an optical splitter that is connected to the optical line terminal via one first optical fiber, and a plurality of optical network units that are connected to the optical splitter via respective second optical fibers. The plurality of optical network units communicate with the optical line terminal using an optical signal of a working wavelength uniquely assigned to each of them. The optical line terminal communicates with an optical network unit that is connected to the optical splitter using an optical signal of a working wavelength and an optical signal of a spare wavelength that is common to a plurality of optical networks.

Abstract: Embodiments of the present invention provide an optical branching assembly, a passive optical network, and an optical transmission method, which relate to the field of communications and are used to implement a functional diversity of the optical branching assembly. The optical branching assembly includes: a substrate and an optical power distribution area disposed on a surface of the substrate, where the optical power distribution area is coupled to a first optical waveguide, multiple second optical waveguides, and at least one third optical waveguide, and is used to distribute optical power of an optical signal, transmitted through the first optical waveguide, to each of the second optical waveguides and the at least one third optical waveguide; and the third optical waveguide is coupled to the first optical waveguide, where a reflective material is disposed on the third optical waveguide.

Abstract: Completed modular optical switch architecture comprises a number of modular components. The components can be combined in various manners in order to provide different sized switches with different characteristics to meet particular requirements.

Abstract: The present invention discloses a method, an apparatus, an optical component and an optical network system for controlling an operating temperature of an optical component. The method includes: acquiring an external ambient temperature of the optical component; setting a target control temperature of a temperature controller according to the external ambient temperature, where the target control temperature is a function value of the external ambient temperature, and the target control temperature is within a range from an operating temperature lower limit of a laser to an operating temperature upper limit of the laser; and controlling, according to the target control temperature, an operating temperature of the optical component by means of heating or cooling by using the temperature controller.

Abstract: A method in an optical Wavelength Selective Switch, WSS, for multidirectional switching of optical signals. The optical WSS comprises a reflective element, a first tributary port and a second tributary port. The optical WSS switches (304) an optical signal between the first tributary port and the second tributary port with the reflective element.

Abstract: An optical switch comprises a first stage comprising N optical inputs, wherein N is an integer power of 2 and is 16 or greater, and N first sub-switches, wherein each first sub-switch comprises 1 of the optical inputs and 4 first outputs, and a second stage coupled to the first stage and comprising 16 second sub-switches, wherein each second sub-switch comprises M second inputs and M second outputs, and wherein M is equal to N/4.

Abstract: The present application relates to multi-stage amplitude modulation-based methods, apparatuses, and systems for coding and decoding a visible light signal. The coding method includes the following steps: dividing to-be-transmitted information into multiple information units, where each information unit includes multiple bits; converting the multiple information units into multiple electrical signal units indicated by at least three levels, where an interval indicated by a first level in the at least three levels exists between adjacent electrical signal units, and each electrical signal unit uses a combination of other levels in the at least three levels to represent the multiple bits of a corresponding information unit; combining the electrical signal units to obtain a coded electrical signal; and transmitting the coded electrical signal in a visible light signal form.

Abstract: An example of a power and modulation circuit utilizes a very high frequency switching power converter to supply drive current power to cause a solid state light source to emit light. The power converter is configured to convert power from a power source to direct current to supply via the output to the light source, at least in part by a switching function of the power converter at a very high frequency rate. The circuit, in such an example, also includes a control circuit coupled to be responsive to input data and control operation of the power converter so that the current output to drive the light source modulates the light emitted from the light source to also carry the input data.

Abstract: The present disclosure provides an apparatus, a system and a method for wireless data transmission by using a display backlight. The apparatus for transmitting wireless data by using a display backlight according to the present disclosure may include: a data storage unit for storing data to be transmitted; a main control unit for reading the data stored in the data storage unit; a signal modulation unit for modulating the data with a predetermined signal modulation method under the control of the main control unit to generate and output a sequence of switching pulse signals; a light source driving circuit for generating backlight driving switching pulse signals according to the sequence of switching pulse signals; and a display backlight member for outputting a sequence of light and shade signals.

Abstract: A time synchronization apparatus and method for automatically detecting the asymmetry of an optical fiber.

Abstract: A communication system includes a first and second trunk terminals, a plurality of communication trunks disposed along a floor of a body of water, and power feed equipment. Each communication trunk couples the first trunk terminal to the second trunk terminal and includes at least one signal amplifier configured to amplify a signal conveyed along the corresponding communication trunk. The power feed equipment is coupled to the plurality of communication trunks and is configured to deliver power along each communication trunk to power the at least one signal amplifier of the communication trunk. The power feed equipment is also configured to receive a shunt fault notification identifying an electrical shunt fault along a faulted communication trunk of the plurality of communication trunks. In response to the shunt fault notification, the power feed equipment is configured to cease delivery of power along at least one communication trunk.

Abstract: An optical communication system includes: a first network-side device and a second network-side device each coupled to a communication network; and a first terminal-side device and a second terminal-side device configured to communicate with the first network-side device and the second network-side device by being coupled to the first network-side device and the second network-side device via a first communication cable and a second communication cable, respectively, wherein the first network-side device is coupled to the first terminal-side device via the communication network, the second network-side device, and a third communication cable for coupling the second network-side device and the first terminal-side device so as to communicate between the first network-side device and the first terminal-side device.

Abstract: Provided herein is a wavelength/bandwidth tunable optical filter capable of flexibly tuning a wavelength and bandwidth, the wavelength/bandwidth tunable optical filter including an optical circulator configured to receive a WDM (Wavelength-Division-Multiplexing) optical signal from an optical cable; and a plurality of wavelength-tunable optical filters configured to receive the WDM optical signal via the optical circulator, wherein the plurality of wavelength-tunable optical filters reflect wavelengths of different bandwidths from one another.

Abstract: A method includes receiving an optical signal through an optical link and determining a receiving power for the optical link. The method further includes comparing the receiving power for the optical link to a first receiving power threshold and transitioning a clock and data recovery circuit form a normal mode to a holdover mode when the receiving power is less than the first receiving power threshold. The clock and data recovery circuit, when operating in the holdover mode, configured to hold a recovered clock to a known-good clock frequency. When the receiving power for the optical link is greater than a second receiving power threshold, the method initiates a transition of the clock and data recovery circuit from the holdover mode to the normal mode and reacquires synchronization between the recovered clock and a current rate of the incoming data stream using the known-good clock frequency.

Abstract: Techniques for transmitting a data signal through an optical communications system. An encoder is configured to encode the data signal to generate symbols to be modulated onto an optical carrier. Each symbol encodes multiple bits of data and includes a first portion selected from a first constellation and a second portion selected from a second constellation. The first and second constellations have respective different average amplitudes. Each of the first and second constellations have a cardinality of at least two and the cardinality of the first constellation is greater than the cardinality of the second constellation. A modulator is configured to modulate a first frame of the optical signal using the first portion and modulate a second frame of the optical signal using the second portion. A selection of one frame of the optical signal to be used as the first frame encodes at least 1 bit of data.

Abstract: The present disclosure provides an apparatus, a system and a method for wireless data transmission by using a display backlight. The apparatus for transmitting wireless data by using a display backlight according to the present disclosure may include: a data storage unit for storing data to be transmitted; a main control unit for reading the data stored in the data storage unit; a signal modulation unit for modulating the data with a predetermined signal modulation method under the control of the main control unit to generate and output a sequence of switching pulse signals; a light source driving circuit for generating backlight driving switching pulse signals according to the sequence of switching pulse signals; and a display backlight member for outputting a sequence of light and shade signals.

Abstract: A system for transmitting data using light includes a plurality of light sources configured to transmit light at non-overlapping wavelengths, processing electronics, and a diffuser configured to diffuse the transmission of light. The processing electronics assign the plurality of light sources to a plurality of channels, accept a data stream, allocate the data stream to the channels, and modulate a transmission of the light using the allocated data stream, where the allocated data used to modulate a first light source of the plurality of light sources is separate from the allocated data used to modulate a second light source of the plurality of light sources.

Abstract: A visible light communication (VLC) device and method for discovery and association with a VLC infrastructure node are disclosed. The VLC device is configured to receive a beacon frame from a VLC infrastructure node. The VLC device is further configured to transmit an association request to the VLC infrastructure node. The association request includes an indication of physical layer (PHY) capabilities and an indication of medium access control (MAC) capabilities of the VLC device. The VLC device is further configured to receive an association response from the VLC infrastructure node. The association response includes information for use in communicating with the VLC infrastructure node.