Abstract: Aspects are generally directed to an inter-satellite communication system and method of communicating between satellites. In one example, an inter-satellite communication system includes a first satellite transceiver having an entrance aperture, and a non-mechanical beamsteering device configured to steer a first beam of encoded optical data over a field of view thereof. The first satellite transceiver may include coarse steering optics configured to extend a field of regard of the non-mechanical beamsteering device. During a transmit mode, the coarse steering optics are positioned to transmit the first beam of encoded optical data through the entrance aperture in a direction of a second satellite transceiver. The first satellite transceiver may also include a beam splitter positioned, during a receive mode, to receive a second beam of encoded optical data from the second satellite transceiver and direct the second beam of encoded optical data to an optical sensor.

Abstract: An apparatus and method for tracking a laser communication signal of interest incident on a focal plane array (FPA) identifies a plurality of “hotspots” in a scene of interest, and aligns a hotspot that is a signal of interest (SOI) or beacon component thereof with the FPA. Hotspot centroids can be estimated within a fraction of an FPA pixel by considering squares of four pixels and comparing their signal amplitudes. A multi-spot calculation is used to improve the position estimates of all of the hotspots by applying a Kalman filter to the hotspot position data and assuming that the relative hotspots positions are fixed. The calculation is periodically repeated to enable tracking of the SOI. Amplitude variability of the hotspots is accommodated by weighting the hotspot contributions according to their intensities. In embodiments, estimation error of the SOI centroid is less than a smallest dimension of the FPA pixels.

Abstract: A hybrid optical-RF device, called a “stamp cell” herein, may be a small, passive repeating device that is designed to be placed close to User Equipment (UE) such that the UE only needs to reach a few meters using high frequency RF signals. The stamp cell may directly convert the received RF signal to an optical signal which may be transmitted to an optical receiver mounted on a traditional cell tower. Similarly, in the downlink direction, the stamp cell may receive optical signals from the cell tower and convert the optical signals to high frequency RF signals, which may be received by the UE.

Abstract: An optical transmitter and a method for driving the optical transmitter include generating a modulated signal having an operation frequency corresponding to a communication channel, obtaining a first optical signal using passing a portion of the modulated signal through a first optical path, obtaining a second optical signal using passing another portion of the modulated signal through a second optical path having a different spectral response curve from that of the first optical path, converting the first optical signal to a first electrical signal, converting the second optical signal to a second electrical signal, obtaining an error signal between the first and second electrical signals, finding a maximum of the error signal by varying the operation frequency over a predetermined frequency range of the communication channel, and determining that the operation frequency is matched to a passband of a frequency reshaper when the error signal reaches the maximum.

Abstract: A disclosed method for configuring an optical network includes determining that a measure of performance for a first optical path is approaching a safe threshold and designating the first optical path as at risk for performance degradation due to additional traffic. The method also includes, in response to adding a new optical path, calculating a system margin for the first optical path representing a difference between an OSNR delivered on the first optical path and a required OSNR for error-free operation on the first optical path, determining that the system margin is insufficient to meet an applicable performance level, modifying an operating parameter of a transmitter or receiver of the first optical path and refraining from calculating a system margin for a second optical path that is not designated as at risk for performance degradation. The method may be implemented by a network management system of the optical network.

Abstract: Techniques for using planar photonic switch fabrics with reduced waveguide crossings are described. In one embodiment, a system is provided that comprises a memory that stores computer-executable components and a processor that executes computer-executable components stored in the memory. In one implementation, the computer-executable components comprise an arrangement component that arranges a first planar switch fabric topology. The computer-executable components further comprise a transformation component that interleaves a plurality of inputs of the first planar switch fabric topology and a plurality of outputs of the first planar switch fabric topology to form a second planar switch fabric topology, the second planar switch fabric topology having a lower number of waveguide crossings than the first planar switch fabric topology.

Abstract: Systems and Methods for reducing distortion due to bursts of upstream transmission in an HFC CATV network. In some preferred systems, the functionality of an Optical Network Unit (ONU) may occur within a node or amplifier along a direction upstream from a subscriber's home.

Abstract: In some embodiments, an apparatus includes an optical transceiver configured to be operatively coupled to a network. The optical transceiver includes a photo diode and a processor configured to be operatively coupled to the photo diode. The photo diode is configured to measure a receiver optical power (ROP) value and send the ROP value to the processor. The processor is configured to measure a bit error rate (BER) value of a digital modulated signal at an input port of the optical transceiver. The processor is also configured to determine an estimated optical signal noise ratio (OSNR) value at the input port of the optical transceiver based on the ROP value and the BER value. The processor is configured to send a signal indicating the estimated OSNR value such that a planned route is selected for sending data signals through within the optical transceiver based on the estimated OSNR value.

Abstract: Distributed communications systems providing and supporting radio frequency (RF) communication services and digital data services, and related components and methods are disclosed. The RF communication services can be distributed over optical fiber to client devices, such as remote units for example. Power can also be distributed over electrical medium that is provided to distribute digital data services, if desired, to provide power to remote communications devices and/or client devices coupled to the remote communications devices for operation. In this manner, as an example, the same electrical medium used to transport digital data signals in the distributed antenna system can also be employed to provide power to the remote communications devices and/or client devices coupled to the remote communications devices.

Abstract: A method for conveying information through an optical fiber link between a transmitter and a receiver of an optical communication system. The method includes generating, by the transmitter, a predetermined spectral change, and inserting the predetermined spectral change into an optical fiber link for transmission to the receiver. A detector associated with the receiver detects the predetermined spectral change in an optical signal received through the optical fiber link, and generates a detection signal in accordance with the detection result. The detector is independent of a digital signal processor of the receiver that is configured to recover data modulated on the optical signal received through the optical fiber link.

Abstract: Embodiments of the present invention relate to method and device for measuring optical signal-to-noise ratio (OSNR). A method for measuring an OSNR of a signal of interest may comprise: obtaining spectrum of the signal of interest, the spectrum including power spectrum density distribution of the signal of interest in a channel bandwidth B; obtaining spectrum of a comparative signal that has the same spectrum characteristics as but different OSNR than the signal of interest, the spectrum including power spectrum density distribution of the comparative signal in the channel bandwidth B; and calculating the OSNR of the signal of interest by using the spectrum of the signal of interest and the spectrum of a comparative signal.

Abstract: A method and an apparatus for setting a quiet window in a passive optical network system are provided. A first response time from a time after an optical line terminal (OLT) transmits a serial number request up to a time in which the OLT receives a first response signal to the serial number request is measured, and a second response time up to a time in which the OLT receives a final response signal to the serial number request is measured. In addition, distance information of an optical network unit (ONU) including the first response time and the second response time is acquired.

Abstract: Optoelectronic oscillator systems and an optoelectronic oscillator noise reduction method. One example of an optoelectronic oscillator system includes an optical source positioned at a first end of a fiber-optic path, the optical source being configured to transmit an optical signal along the fiber-optic path, an optical modulator positioned to receive and modulate the optical signal based on at least a reference signal, a retro-reflector positioned at a second end of the fiber-optic path, the retro-reflector being configured to receive and retro-reflect the optical signal, the retro-reflected optical signal having at least a frequency range of inherent fiber noise canceled, and an optical circulator positioned along the fiber-optic path between the optical modulator and the retro-reflector, the optical circulator being configured to direct the optical signal to the retro-reflector and direct the retro-reflected optical signal along a feedback path to a first photodetector to generate the reference signal.

Abstract: In an electronic component mounting device, a first multiplexing device of a head section which is attachable to and detachable from a Y-axis slider is connected to a second multiplexing device through an electric communication cable. The first multiplexing device, from which the cable is likely to be removed, is connected through the electric communication cable for which the communication failure due to dust or the like is relatively unlikely to occur. Second and third multiplexing devices, from which cables are less likely to be removed, are connected through the optical communication cable. The second multiplexing device separates data directed to the input and output device, among frame data received from the third multiplexing device, multiplexes only data directed to the first multiplexing device from the second multiplexing device, and transfers the multiplexed data to the first multiplexing device by the electric communication cable.

Abstract: Systems and methods are provided for an optical network unit (ONU) to automatically set its output power level for messages to be transmitted on a passive optical network. The ONU can autonomously determine the appropriate power level based on information provided to the ONU by an optical line terminal (OLT) and characterization by the ONU of optical signals it receives from the fiber. Specifically, the OLT can provide the ONU with control data indicative of the power level used by the OLT to transmit the message and the desired power level of the OLT for messages from the ONU. The ONU can measure the power level of at least one message received from the OLT and determine the path loss based on the measured power and the control data. The ONU can then automatically determine a suitable power level for its response message such that unacceptable levels of crosstalk between channels are avoided without having to perform an iterative power-leveling process that otherwise may introduce significant delays.

Abstract: An optical IQ demodulator that does not require a power-consuming DSP is disclosed. A DC offset is added to one of the I and Q optical signal components at an IQ transmitter. After mixing with an LO signal and differential detection at the receiver, this DC offset results in a heterodyne-frequency tone in each of the quadrature detection channels of the receiver. The phase of this oscillation is recovered using a PLL circuit, which output is used to separate the transmitter I and Q channels for decoding thereof using conventional electronics.

Abstract: A transceiver device includes a time of flight circuit configured to emit a modulated light transmit signal and to receive a modulated light receive signal. The transceiver device includes a control module configured to control a transmission of a modulated light transmit signal by the time of flight circuit to an access control device. The modulated light transmit signal includes information related to a transmission access request. The control module is further configured to control an establishment of a wireless transmission channel based on a modulated light receive signal received by the time of flight circuit from the access control device. The modulated light receive signal includes information for establishing the wireless transmission channel.

Abstract: A system monitors optical performance of an optical link within an optical network. The system includes an optical transmitter having an expanded-spectrum pilot-tone modulator for modulating an expanded-spectrum pilot tone onto a high-speed data signal to generate an expanded-spectrum optical signal and an optical receiver for receiving the expanded-spectrum optical signal and for detecting and decoding the expanded-spectrum pilot tone to enable monitoring of the optical performance of the optical link.

Abstract: Disclosed is a communication apparatus including a synchronization signal detector configured to detect a synchronization signal received from other communication apparatus coupled to the communication apparatus, wherein the other communication apparatus sends a quantum signal generated by a first light source to the communication apparatus, and a second light source configured to generate a decoy signal to be added to a quantum signal that is to be sent to the other communication apparatus according to a result of the detection of the synchronization signal.

Abstract: A method includes monitoring a parameter of an optical signal transmitted between two endpoints via an optical fiber. The optical fiber may be manipulated to modulate the parameter without disconnecting either endpoint of the optical fiber. Data in accordance with the modulation of the monitored parameter may be identified. A portion of the optical fiber may be wrapped around a high order mode filter (HOMF) that includes a grooved cylinder or mandrel suitable for wrapping the optical fiber. The monitored parameter may include a received power parameter. The HOMF may be a variable diameter HOMF that can be transitioned between a wrapped or attenuating diameter and an unwrapped or non-attenuating diameter in accordance with a data pattern. The wrapped and unwrapped diameters may be defined relative to a threshold diameter, above which the monitored parameter may be independent of the diameter.