Abstract: Because of the line-of-sight character of optical wireless communication and a limited field-of-view of optical receivers, the coverage of an access point and the overlapping coverage area of adjacent access points in an optical system are smaller as compared to a RF system. It turns more challenging to support an end point (110) to roam securely in an optical multi-cell wireless communication network. To speed up the derivation of a new pairwise transient key with a new access point during a handover procedure, the end point of this invention comprises a controller (118) that is configured to act as a second supplicant (1181), on behalf of a first supplicant (1186) comprised in a host processor (1185), to communicate with an authenticator to establish a new pairwise transient key for the end point (110) and a candidate access point, and an active pairwise transient key with the currently associated access point is used to secure the communication for new key derivation.

Abstract: A first device may generate optical signals of different polarizations. Photodiodes may use the optical signals to transmit wireless signals at different polarizations and at a frequency greater than 100 GHz using the optical signals. A second device may receive the wireless signals and may convert the wireless signals into optical signals. A Stokes vector receiver on the second device may generate Stokes vectors based on the optical signals. Control circuitry on the second device may use the Stokes vectors generated for a series of training data in the wireless signals to generate a rotation matrix that characterizes polarization rotation between the first and second devices. The control circuitry may multiply wireless data in subsequently received wireless signals by the rotation matrix to mitigate the polarization rotation and other transmission impairments while using minimal resources.

Abstract: Aspects of the present disclosure describe systems, methods, and structures for aberration correction of optical phased arrays that employ a corrective optical path difference (OPD) in the near-field of an OPA to correct or cancel out aberrations in emitted beams of the OPA including those reaching far-field distances by generating a spatially-varying OPD across the aperture of the OPA that is substantially equal and opposite to an equivalent OPD of the aberration(s).

Abstract: The present invention relates to a fiber branch structure for spatial optical communication for transmitting information by emitting communication light. The fiber branch structure is provided with: a light emitter configured to emit communication light; a light emission controller configured to control the light emitter; an optical fiber configured to transmit the light emitted from the light emitter; a distributor configured to distribute the light, the distributer being optically coupled to an output terminal of the optical fiber; and an optical fiber group optically coupled to a plurality of output terminals of the distributor. According to the present invention, a communication area can be established without blind spots. That is, the fiber branch structure for spatial optical communication according to the present invention includes an optical fiber group optically coupled to a plurality of output terminals of the distributor.

Abstract: A quantizer includes: a clipper configured to clip a portion exceeding a quantization range of a sample value sampled at a predetermined rate; and a noise shaper configured to determine a plurality of candidates for a quantization level based on the clipped sample value, and outputs, as a quantization value, a value obtained by adding a minimum noise in which a noise in a low-frequency region is minimum among noises generated in each candidate to the sample value before clipping.

Abstract: An apparatus and method for signaling and transmitting data through an optical link is described. The apparatus may include a connector including a first plurality of contacts compatible with an enhanced SFP (SFP+) connector. The connector further includes an additional contact formed at a space adjacent to the first plurality of contacts. A tone generator couples to the additional contact to receive a first signal and to generate a first distinct tone indicative of the first signal for transmission via the additional contact. The method may include generating a first distinct tone indicative of a first signal providing control or status of an apparatus and transmitting or receiving a differential data signal over a portion of a first plurality of contacts compatible with an enhanced SFP (SFP+) connector. The first distinct tone is transmitted over the additional contact formed in a space adjacent to the first plurality of contacts.

Abstract: A plurality of digital processors may be used to adjust phases in a plurality of phase modulators. The plurality of digital processors may receive a periodic pulse, or heartbeat signal, from a synchronization controller in order to control the digital processors. The synchronization controller may output an additional signal used to determine and to control the phase of the signals output from the plurality of phase modulators.

Abstract: An optically-monitored and/or optically-controlled electronic device is described. The device includes at least one of a semiconductor transistor or a semiconductor diode. An optical detector is configured to detect light emitted by the at least one of the semiconductor transistor or the semiconductor diode during operation. A signal processor is configured to communicate with the optical detector to receive information regarding the light detected. The signal processor is further configured to provide information concerning at least one of an electrical current flowing in, a temperature of, or a condition of the at least one of the semiconductor transistor or the semiconductor diode during operation.

Abstract: Systems, methods and apparatus are provided for a reusable, client-server based ecosystem designed to support content-aware, LiFi-powered transfer of large-scale, semi-structured data files. Containerized client-side applications may include a LiFi communication engine (LCE), a job control engine (JCE), and an execution hub that is configured to interface with the JCE, the LCE, job stakeholders and downstream applications. A central server may include a server-side LCE configured for two-way communication with the client-side LCE. Each LCE may be configured to cluster semi-structured data into data packets, broadcast data packets using an LED array, receive data packets using an array of photoreceptors and synchronize received data packets.

Abstract: Aspects of the subject disclosure may include, for example, a device in which a processing system receives an electromagnetic signal including a plurality of packets, stores a copy of the packets in a memory, converts the signal to an optical signal, and splits the optical signal into first and second optical signals each including the packets. A first converter and second converter then convert the optical signals to electromagnetic signals. A timing coordinator sends a timing signal to the memory and to the first and second converters, resulting in simultaneous release of a copied packet from the memory and first and second packets from the first and second converters. The system compares the copied packet with the first and second packets; if those packets are identical to the copied packet, the system outputs the first and second packets in outgoing signals. Other embodiments are disclosed.

Abstract: A free-space optical (FSO) terminal may include a controller and an alignment sensor. The alignment sensor includes a set of detectors. Each detector generates a signal responsive to receiving electromagnetic radiation at a detection surface. The set of detectors includes an inner set of detectors and an outer set of detectors. The detection surfaces of the inner detectors and the outer detectors may be aligned in a plane. The outer set of detectors surround the inner set of detectors (e.g., in the plane) and have larger detection surfaces than the inner set of detectors. During a tracking mode, the controller is configured to adjust an orientation of the FSO terminal based on signals from the inner set of detectors. During an acquisition mode, the controller is configured to adjust the orientation of the FSO terminal based on signals from the outer set of detectors.

Abstract: Implementations described and claimed herein provide systems and methods for an optical domain controller for managing and maintaining a record of network component configuration and interconnections. The optical domain controller detects changes in a configuration of optical network elements in response to a requested service from the network, coordinates additional changes in configurations to optical network elements that may be affected by the detected change, communicates with the optical network elements to incorporate the changes to the configurations of the network element, and stores the configurations and states of the network elements. The use of the optical domain controller may thus replace or supplement a database storing network configuration information by automatically managing changes to the network as new services are instantiated directly on the optical network elements.

Abstract: A random acoustic phase scrambler device is installed in-line with a telecommunications fiber link to prevent voice detection via fiber links. The device includes a transducer to produce vibrations; a length of optical fiber positioned to receive the vibration from the transducer; and a random acoustic phase driver configured to control the intensity and frequency of the vibrations. The transducer produces randomized vibrations within an acoustic bandwidth. The device is configured to introduce device-induced phase changes to signals within the telecommunications fiber link. The bandwidth of the device-induced phase changes is greater than the bandwidth of voice-induced phase changes, and the device-induced phase changes are greater in intensity than the voice-induced phase changes. The device-induced phase changes mask voice-induced phase changes through the telecommunications fiber link that are otherwise detectable by voice detection equipment tapped to the telecommunications fiber link.

Abstract: An object is to provide a communication system, a base station, and a communication method that can avoid a state in which an RF wireless communication cannot be started due to the quality of optical wireless communication. In an optical communication system according to the present invention, a base station device repeatedly transmits an authentication information frame addressed to a terminal device at a predetermined cycle by the optical wireless communication, the frame including authentication information for connection to the terminal device by the RF wireless communication. Even if the terminal fails to acquire the authentication information at a certain timing due to the quality of optical wireless communication, the communication system has a mechanism that acquires the same authentication information at regular time intervals, so that terminal authentication processing can be performed at the time when the terminal acquires the authentication information.

Abstract: A distorter coefficient updating apparatus, a distorter coefficient updating method, and a digital predistortion apparatus. The distorter coefficient updating apparatus is configured at an optical receiver side, and comprises a processor configured to: perform re-distortion processing on a signal after decision according to a first distorter coefficient to generate a first reference signal; and calculate a second distorter coefficient according to the first reference signal and a signal before decision, or according to the first reference signal, the signal after decision, and the signal before decision The second distorter coefficient is fed back to the processor as the first distorter coefficient of the processor in a next update, and the second distorter coefficient is fed back to a predistorter on an optical transmitter side as a predistortion coefficient for the predistorter to perform a predistortion processing on a signal input to the predistorter.

Abstract: A receiver circuit is disclosed and is configured to receive an optical signal. The receiver circuit includes a receiving circuit configured to receive the optical signal and convert the optical signal from a duobinary signal format into a binary signal based on a plurality of decision thresholds. The receiver circuit also includes a clock data recovery circuit configured to sample the binary signal per data period at a first time instant based on a predetermined clock data recovery technique, and sample the binary signal per data period at a second time instant offset from the first instant, as well as determine an intermediate sample based on an offset for decoding a transmitted bit sequence according to soft information based on the samples.

Abstract: Disclosed is a method for transmitting a signal by a transmission terminal in optical wireless communication. The method may comprise: applying a phase pattern to the wavefront of an optical signal; and transmitting the optical signal. Further, the phase pattern may be determined on the basis of the optical phase conversion characteristics of a phase mask provided in the transmission terminal.

Abstract: A signal processing device processes reception signals of optical signals received by a receiver when the optical signals transmitted from a transmitter are propagated to the receiver via a plurality of paths, and includes: a signal-to-noise ratio calculating unit that calculates signal-to-noise ratios of the optical signals that have been propagated through the respective paths, from propagation distances of the optical signals in the respective paths, intensities of the optical signals transmitted from the transmitter, and intensities of noise with respect to the optical signals transmitted from the transmitter; an amplitude adjusting unit that adjusts amplitudes of the reception signals of the optical signals that have been propagated through the respective paths, using the corresponding signal-to-noise ratios calculated by the signal-to-noise ratio calculating unit; and a signal combining unit that combines the reception signals whose amplitudes have been adjusted by the amplitude adjusting unit.

Abstract: The present disclosure is directed to systems and methods of providing the next generation of quantum enabled cyber security systems. Such systems include a quantum network of satellites that will provide global coverage. The quantum satellite network includes quantum subnetworks comprised of LEO satellites. Some of these LEO satellite-based quantum subnetworks are connected to a subnetwork of MEO satellites. The MEO satellite subnetworks may then be interconnected to the global network of GEO satellites. The LEO/MEO satellites may also be used to interconnect terrestrial quantum networks. Each quantum communication subnetwork may be based on the cluster state concept.

Abstract: Provided is a signal processor provided in a transceiver for transmitting and receiving a radio signal, and including a branch unit, a detection unit, a determination unit, and a power source controller. The branch unit branches a transmission signal and acquires a branch signal. The detection unit detects the branch signal and acquires a voltage value of the branch signal. The determination unit compares the voltage value of the branch signal with a threshold voltage previously stored in a storage unit and determines whether the voltage value of the branch signal is equal to or greater than the threshold voltage. The power source controller controls turning on and off of a power source for a reception signal amplifier of the transceiver according to a determination result determined by the determination unit.