Abstract: A system and method for providing quantum entanglement using a hybrid space-fiber quantum network are described. The hybrid space-fiber quantum network includes a communications hub located proximate to an optical ground station and also includes an aerial entangled particle source, such as an entangled photon source attached to a satellite, drone, aircraft, etc. An atmospheric or free-space channel is used to distribute quantum entanglement between optical ground stations that are separated by geographic distances, via the aerial entangled particle source. Also, fiber optic links are connected to the communications hub located proximate to the optical ground station. The communications hub includes optical switches that enable any of the fiber optic links connected to the communications hub to receive or send distributed quantum entanglement to a remotely located recipient endpoint via the atmospheric or free-space channel.

Abstract: A communication resource in a network environment analyzes upstream communications received over multiple passive optical networks. The upstream communications are received from multiple client devices in different passive optical networks. Based on analysis of the upstream communications, via an active or passive approach, a corresponding communication resource detects in which of the multiple passive optical networks each of the client devices reside. A scheduler resource can be configured to use the class information as a basis to schedule subsequent upstream communication, avoiding occurrence of optical beat interference.

Abstract: A method, device and system for implementing a long reach passive optical network are provided. Uplink optical burst packets are transmitted by an optical network unit. The uplink optical burst packets are converted into an electrical signal and then a continuous optical signal. The continuous optical signal is transmitted to a receiving device.

Abstract: Methods and apparatus for line coding in a communications network are described. According to one embodiment of the invention, downstream communications traffic bits are received and mapped into downstream bit positions of a transmission structure. A pre-selected bit in each upstream bit positions of the transmission structure is provided to form a downstream transmission structure. A downstream optical signal carrying the downstream transmission structure is generated for transmission. Upstream communications traffic bits are also received and mapped into the upstream bit positions of the transmission structure to form an upstream transmission structure. An upstream optical signal carrying the upstream transmission structure is generated for transmission.

Abstract: Embodiments of the present invention provide a repeater, including a local unit and a remote unit. The local unit includes a base station interface unit, multiple local basic units and a controller. The remote unit includes multiple remote basic units. The controller is configured to generate, according to a down-tilt angle and/or azimuth angle of a downlink signal instructed by a control instruction, a downlink signal phase for each remote basic unit. The multiple local basic units each are configured to perform, according to the downlink signal phase generated by the controller for a corresponding remote basic unit, phase adjustment on the downlink signal sent by the base station interface unit. The multiple remote basic units each are configured to receive the downlink signal sent by a corresponding local basic unit and to send the downlink signal.

Abstract: An iterative method is provided for progressively building an end-to-end entanglement between qubits in first and second end nodes (91, 92) of a chain of nodes whose intermediate nodes (90) are quantum repeaters. At each iteration, a current operative repeater (90) of the chain merges an entanglement existing between qubits in the first end node (91) and the operative repeater, with a local entanglement formed between qubits in the operative repeater and its neighbor node towards the second end node (92). For the first iteration, the operative repeater is the neighbor of the first end node (91); thereafter, for each new iteration the operative repeater shifts one node further along the chain toward the second end node (92). A quantum repeater adapted for implementing this method is also provided.

Abstract: A method, device and system for implementing a long reach passive optical network (LR-PON) are provided, which solve the problem that the cost for establishing an LR-PON system is high. The method includes: receiving an uplink burst packet transmitted by an optical network unit (ONU) in a burst manner (101), converting a burst optical signal of the uplink burst packet into a continuous optical signal, and transmitting the continuous optical signal to a receiving device (105). The present invention is applicable to an LR-PON.

Abstract: A repeater (1) includes a master unit (2) for communicating with a base station of a mobile network, a plurality of remote units (3) for communicating with mobile communications terminals, and a common optical waveguide (4) connecting the remote units (3) with the master unit (2) for transmitting the optical signals from each of the remote units (3) to the master unit (2). The remote units (3) include, as a transmitter for the optical signals, a laser (7) of a construction similar or somewhat identical to that of the other lasers (7). The lasers (7) have similar or somewhat identical nominal wavelengths (?N), and the individual lasers (7) are selected by adjusting their operating temperatures (TD1-TD4) in such a way that each laser transmits on a different transmission wavelength (?ü1-?ü4).

Abstract: Provided is an optical relay system (10) which is capable of suppressing wasteful power consumption of an entire system to a low level. The optical relay system (10) includes a plurality of relay devices (30) and a network control device (20). The network control device (20) causes an optical signal to be regenerated by a regenerative repeater (35) within the relay device (30) existing at an upstream of the relay device (30) reporting that the optical signal has deteriorated by a degree exceeding a predetermined level. Further, the network control device (20) causes the regenerative repeater (35) to stop regenerating the signal in a case where deterioration of the signal remains within an allowable range even when the regenerative repeater (35) stops regenerating the signal.

Abstract: A vehicle network system is provided with a plurality of star networks, a plurality of devices mounted on a vehicle are connected in a star shape through respective branch lines in each of the star networks, and a trunk line for connecting the plurality of star networks, the branch lines are communication lines for optical communications, and the trunk line is a communication line for electric communication.

Abstract: A system for transporting signals through PON, including a device for transporting optical network signals and a device for transporting optical line signals, wherein: the device for transporting optical network signals is adapted to map upstream optical signals with a PON frame format to upstream optical channel data unit signals, to convert into upstream signals with an optical channel transport unit format, and to transport to the device for transporting optical line signals through OTN; and to perform corresponding downstream processing; the device for transporting optical line signals is adapted to convert the upstream signals into upstream optical channel data unit signals, to de-map to upstream optical signals with a PON frame format, and to transport to an optical line terminal; and to perform corresponding downstream processing. The invention further discloses relevant devices and methods.

Abstract: A signal detect circuit includes a signal strength measuring differential output linear amplifier. A positive peak detection circuit is coupled to the positive output terminal of the linear amplifier and generates a signal that represents a peak magnitude of a signal received from the positive output terminal. Likewise, a negative peak detection circuit is coupled to the negative output terminal of the linear amplifier and generates a signal that represents a peak magnitude of a signal received from the negative output terminal. Upon power up of the signal detect circuit, a comparison circuit detects when the positive and negative peak signal magnitudes has both exceed respective values at least once. Once this occurs, the comparison circuit compares an interpolation of the positive peak signal and the negative peak signal with the value. If the interpolated signal falls below the value, the comparison circuit generates a signal representing that no signal is being received.

Abstract: A modulation device comprises for each carrier frequency: means of discrimination between a signal coming from a first channel of a communications link and a signal coming from a second channel of said link, so as to obtain differentiated first and second signals; first assigning means, enabling the assigning of the first differentiated signal to one of the two modulation arms, and the second differentiated signal to the other of the two modulation arms.

Abstract: An optical wireless local area network using line of sight optical links. The base station and terminal stations are provided with optical transceivers which include a transmitter array and detector array. The transmitter array consists of an array of resonant cavity light emitting diodes integrated using flip-chip technology with a CMOS driver circuit. The driver circuit includes constant bias, current peaking and charge extraction. The driver circuitry is compact and can be confined within a region underlying the corresponding light source. The detector array consists of an array of photo diodes, provided with sense circuitry consisting of a pre-amplifier and post-amplifier. The diodes and sense circuitry are also integrated using a flip-chip technique. The light emitter and the detector may include adaptive optical elements to steer and/or focus the light beams.

Abstract: In accordance with the teachings of the present invention, a system and method for managing communication in a hybrid passive optical network (HPON) is provided. In a particular embodiment, the method includes transmitting, at a first wavelength, a first configuration message on the HPON. The method also includes receiving at one or more of a plurality of receivers at an optical line terminal (OLT) one or more configuration response messages from one or more optical network units (ONUs) in a first set of ONUs. The method further includes, based on the configuration response messages from the first set of ONUs, associating, in a database, each ONU in the first set of ONUs with the first wavelength and with the receiver receiving the configuration response message from the ONU. The method also includes, after transmitting the first configuration message, transmitting, at a second wavelength, a second configuration message on the HPON.

Abstract: Disclosed is an apparatus for controlling wavelength-division-multiplexed light wherein overall power of wavelength-division-multiplexed light is rendered constant through control for uniformalizing the level of only one wave of maximum power, and wherein the levels of respective channels are made substantially uniform. Optical level control means controls the optical level of propagating wavelength-division-multiplexed light, and a portion of the wavelength-division-multiplexed light output from the output level control means is branched to a tunable optical filter, which selectively outputs the light of each wavelength contained in the wavelength-division-multiplexed light. The light of each wavelength output from the optical filter is photoelectrically converted to an electric signal by photoelectric conversion means.

Abstract: A wavelength-selective routing capability is provided in a single network element by configuring the network element using a combination of add/drop network elements to route individual optical channels of WDM signals among a plurality of optical transmission paths coupled to the network element. Any optical channel of any WDM signal received at the network element can be selectively added, dropped, or routed among the multiple optical transmission paths within and external to the node.

Abstract: An optical repeating system includes an optical transmitter and an optical amplifying repeater. The optical transmitter transmits a supervisory command and a control command to the optical amplifying repeater as a first sub-signal. The supervisory command is a command to supervise internal circuits of the optical amplifying repeater, and the control command is a command to control the optical amplifying repeater. The optical amplifying repeater includes multiple sub-modules each for amplifying and repeating main signals on multiple sets of optical transmission lines. When receiving the supervisory command via the optical transmission line, each sub-module transmits a supervisory signal indicating the supervisory result associated with the supervisory command to an optical receiver as a second sub-signal.

Abstract: A repeater apparatus (1001) is constituted from infrared transmitter sections (1s, 2s, 3s) and infrared receiver sections (1r, 2r, 3r) as well as connection control sections (1C, 2C, 3C) and further a repeater section (101), thereby attaining independent communications with the individual one of several associated equipments with respect to infrared communication apparatus of the direct emission type which supports only one-to-one (1-to-1) or one-to-several (1-to-N) communication schemes, thus enabling achievement of N-to-N communication forms by performing transfer of data information being received by each communication equipment to others.

Abstract: An optical repeater which includes a wavelength converter and a bit rate converter. The wavelength converter converts a wavelength of an optical signal from a first optical network to a wavelength of a second optical network. The bit rate converter converts a bit rate of the optical signal from the first optical network to a bit rate of the second optical network. The optical repeater transmits the optical signal from the first optical network to the second optical network at the converted bit rate and wavelength.