Abstract: In an optical system including an optical input port for projecting an input optical signal onto an optical phased matrix array, an optical phased matrix array including a plurality of individually addressable pixels thereon, each said pixel being drivable within a prescribed range of levels, and an optical output port for collecting a predetermined fraction of said optical signal received from said optical phased matrix array; a method of compensating for phase distortions including the steps of: (a) determining a plurality of transfer functions relating said level of each said pixel to the phase variation each said pixel introduces to light from said input optical signal which is incident thereon; and (b) controlling the level of selected ones of said pixels in accordance with a corresponding transfer function such that said fractional signal received at said output port is modified in phase to substantially compensate for optical phase distortions arising from said optical phased matrix array.

Abstract: A system and method for providing two-way communication of quantum signals, timing signals, and public data is provided. Generally, the system contains a first public data transceiver capable of transmitting and receiving public data in accordance with a predefined timing sequence, a first optical modulator/demodulator capable of transmitting and receiving timing signals in accordance with the predefined timing sequence, a first quantum transceiver capable of transmitting and receiving quantum signals in accordance with the predefined timing sequence, and a first controller connected to the first public data transceiver, the first optical modulator/demodulator, and the first quantum transceiver. The first controller is capable of controlling the transmission of the public data, the timing signals, and the quantum signals in accordance with the predefined timing sequence.

Abstract: Optical correlators are discussed, suitable for in-vehicle distance measurement. The correlators use modulation sequences based on maximal length sequences. A number of different modulation sequences are obtained by generator (32) from a single maximal length sequence, either by adding a variable number of cycles to the end of the maximal length sequence or by starting the maximal length sequence at different points in the sequence.

Abstract: In an Optical Network Termination (ONT), a software controlled system, method and computer readable medium includes measuring a modulation current of an upstream laser transmission. The measured modulation current is processed to determine if a continuous transmission state is present, in response to which, a processor of the ONT sends a signal to shut down the upstream laser transmission. The software solution allows reconfigurable parameters including sample rate and shut down procedure.

Abstract: A detector for detecting cargo in a container has a controller block, a transmitter for transmitting light into the field of view, a receiver for receiving reflected light, and a threshold comparator for determining whether the received light meets a threshold for cargo detection. The receiver includes a DC block for removing effects of ambient light. The detector performs detection multiple times and averages the results, which can be compared with a previously stored condition of cargo presence or absence to increase the detection accuracy further.

Abstract: Optical connection verification schemes that do not cause electromagnetic interference. An all-optical connection verification scheme exploits optical coding based on a standard color scale such as RGB (red, green, blue). An RGB LED source is used to launch a three-color optical signal where the relative (or absolute) magnitudes of the color components identify the connection. On the receiver end, an RGB photodiode measures the relative (or absolute) magnitudes of the color components to verify the connection. Alternatively, one end of the connection may transmit white light with the other end reflecting back a similar three-color signal by use of a color-coded panel reflector.

Abstract: A method and apparatus for switching at least one wavelength component of an optical signal beam from a first state to a second state. The phase characterizing the optical signal component is incremented by interaction with one or more escort beams in a non-linear medium thereby switching the state of the optical signal component on the basis of its incremented phase. Multiple escort beams may also be employed to switch different wavelength components of the signal. The method may be employed to achieve high speed, and substantially transparent, switching of phase, intensity or polarization of a signal.

Abstract: An optical communicating system and method thereof includes first and second terminals. The first terminal has a transmitter for transmitting an interrogating light beam and a receiver for receiving the interrogating light beam. The second terminal has a cats-eye modulating retroreflector (MRR), which includes a modulator for modulating the interrogating light beam received from the transmitter an optical focusing device for focusing the interrogating light beam from the transmitter to the modulator, and a reflector for reflecting the modulated light beam to the receive. It can include a beam deflector positioned at the aperture of the optical focusing device of the catseye MRR to reduce the field of view of the cats-eye MRR, It can also include an angle of arrival sensor for sensing the angle of arrival of the interrogating beam at the second terminal.

Abstract: An optical transfer device for transferring optical signals from a moveable part to a stationary part through an optical transfer medium in order to minimize distortions of the optical signal and increase the effective bandwidth of the signal transit path by minimizing and/or maintaining equal alternate optical signal transit paths from the transmitter to the receiver.

Abstract: A system for configuring fiber optic communication channels between arrays of emitters and detectors comprises: an array of light emitters; an array of light detectors; a bundle of optical fibers disposed between the arrays of light emitters and light detectors for conducting light from the light emitters to the light detectors, wherein a diameter of each optical fiber in the bundle is greater than a diameter of light emitted from each light emitter in the array, and wherein an area cross-section of the bundle of optical fibers overlaps the array of light emitters and the array of light detectors; and logic for mapping at least one emitter to at least one detector to establish at least one fiber optic communication channel between the array of light emitters and the array of light detectors. A counterpart method is also disclosed.

Abstract: An optical binary code transmission system comprising a sender comprising: means for generating a light beam; phase-shifter means; attenuator means whereby the intensity of the lateral modes is sufficiently low for there to exist at the most only one photon in the lateral modes. The phase-shifter means of the sender impose a phase-shift that is chosen randomly to be equal either to 0 or to ?/2 for a first bit value or either to ? or to 3?/2 for a second bit value, and the receiver comprising means for detecting the presence of a photon in the first lateral mode and means for detecting the presence of a photon in the second lateral mode, a first bit value being detected if the presence of a photon is detected in the first lateral mode and a second bit value being detected if the presence of a photon is detected in the second lateral mode.

Abstract: This invention offers a signal-off detection circuit allowing arbitrary setting of an issuing time (response time) of a signal disconnection alarm without being affected by a time constant of a direct current feedback circuit giving an offset voltage to an amplifier for amplifying a data signal. Input data signals per a fixed time determined by a timer is counted by a counter, and a count value is compared with a predetermined set value in a comparator. A configuration is made such that a signal disconnection alarm may be issued by detecting a disconnection state of the data signal according to a comparison result. Thereby, an issuing time of a signal disconnection alarm can be set without being affected by a time constant of a direct current feedback circuit giving an offset voltage to an amplifier for amplifying a data signal of a preceding stage.

Abstract: An all optical fiber bit stream reader system for examining the data contents of an optical fiber involving the conversion of a temporal timing signal into a spatially located signal is provided. The invention generally comprises generating and detecting a signal indicating the presence of data, in a manner which is minimally destructive to the data. One embodiment comprises providing a piece of optical fiber that exhibits a nonlinear response through a two photon absorption process and subsequent emission of a photon corresponding to the two photon absorption process. Such a fiber could comprise a conventional doped silica fiber into which an additional dopant has been introduced. Another embodiment involves modifying the index of refraction of the cladding of the optical fiber line. This causes a fraction of the electric field or light pulse guided through the fiber (if present) to be coupled out of the fiber. Thereafter, the pulse can be detected.

Abstract: The invention concerns a transmitter-receiver device (A, B) which comprises a receiver unit (RXA) for receiving optical signals and transmitter unit (TXA) for transmitting optical signals. Furthermore, the transmitter-receiver device (A, B) comprises a supervising unit (CUA) which supervises the functions of the receiver unit (RXA) and the transmitter unit (TXA). Furthermore, the transmitter-receiver device (A, B) comprises a transmitter circuit which transmits optical communication signals in response to a balanced electric input signal. The invention also concerns a communication system comprising two transmitter-receiver devices (A, B). Through the structure of the invention is by relatively simple means a well functioning device achieved, which, inter alia, makes it possible to supervise the status of the two transmitter-receiver devices (A, B) in an advantageous manner.

Abstract: A polarization mode dispersion (PMD) feedforward compensator compensates first and second order PMD. An optical signal is provided to a PMD detector that senses first and second order PMD in the optical signal and produces control signals for the PMD compensator. The PMD compensator comprises, in series, a first polarization controller, an adjustable delay, a second polarization controller, a first fixed delay, a third polarization controller and a second fixed delay.

Abstract: Disclosed herein is a signal transmission method in a wavelength-division-multiplex (WDM) transmission system. The WDM transmission system comprises a first WDM terminal for transmitting a WDM signal, a second WDM terminal for receiving the WDM signal, and an optical add-drop multiplexer (OADM) node for transmitting to a network element an optical signal of a specific wavelength of the WDM signal which is transmitted between the first and second WDM terminals. The WDM signal is transmitted from the first WDM terminal to the second WDM terminal regardless of whether an optical signal is added or dropped at the OADM node. The network element employs an optical signal of an idle wavelength of the WDM signal that has no transmission data, to transmit another transmission data that is transmitted by the network element.

Abstract: An optical power distribution system and method permits multiple power consuming devices to be selectively supplied with power using a single fiber optic line. In a described embodiment, multiple electrical power consuming well tools are interconnected to a fiber optic line extending into a well. Control modules are interconnected between the fiber optic line and the well tools. When a particular optical wavelength band is transmitted through the fiber optic line, a corresponding one of the control modules causes the respective well tool to be selected for electrical power to be supplied thereto.

Abstract: The present invention provides an optical fiber sensor for traffic monitoring, which comprises a former consisting of an elongated plate, and an optical fiber wound onto at least one surface of the elongated plate. The elongated plate is flexible in a direction transverse to the at least one predetermined property of an optical signal transmitted through the optical fiber sensor. The resulting sensor has a reduced depth which makes it easier to locate within the surface of a traffic route, has increased flexibility to enable to confirm to the surface of the traffic route, and has good cross axis sensitivity rejection.

Abstract: A method for automatic initialization of an optical network is provided. A network management system (NMS) performs remote determination of span losses and sets the operating points of network components. The initialization method comprises remotely and automatically setting target gains of optical amplifiers and signal power levels at transmitters and receivers to required operating values. The methods for initialization of the optical network of the embodiments include gain excursion minimization (GEM) for individual channels passing through amplifiers and/or pre-emphasis of the optical link, where channel powers at the transmitters are biased to compensate for the effects of optical amplifiers gain ripple.

Abstract: The invention concerns an interface device for a fiberoptic communication network. The interface device comprises an electric circuit arrangement 32, a first receiving section 34 for receiving a first transceiver module 24 and a second receiving section 36 for receiving a second transceiver module 26. The interface device also comprises a switching unit 54 for switching said electric circuit arrangement between at least a first and a second state. Furthermore, the interface device includes a controller 56 arranged to automatically control the switching unit 54 in response to at least one control signal such that said first or second states are selected depending on whether at least one control signal is received indicating either that no transceiver module 26 is attached to said second receiving section 36 or that no optical signal above a certain signal level is received by a transceiver module 26 attached to said second receiving section 36.

Abstract: The detection light reflection function is given to PLC type LD, PD or LD/PD modules having light guides and optoelectronic chips (LD, LED, PD or APD) by forming a grating on the light guides which selectively reflects only the detection light.

Abstract: In analyzing radiation from a communication link, single-photon counting can be used to advantage especially at low levels of radiation energy, e.g. in the detection of optical radiation. Preferred detection techniques include methods in which (i) received optical radiation is intensity-modulated in accordance with a preselected code, (ii) wherein it is the optical radiation which is intensity-modulated with the preselected code, and (iii) wherein the radiation modulated with a preselected code is received. For registration of the signals received by a sensing element of a single-photon detector, time of arrival is recorded, optionally in conjunction with registration of time intervals. Advantageously, in the interest of minimizing the number of pulses missed due to close temporal spacing of pulses, D-triggers can be included in counting circuitry.

Abstract: An optically based location system and method of determining a location at a structure include a lighting infrastructure having lights at a structure. Each light is configured to illuminate and to transmit a respective relative or absolute terrestrial position through modulation of emitted light. An optical receiver is configured to detect the lights, to demodulate the position of detected lights, and to determine from the detection a position of the receiver. The receiver can have a conventional optical detector for determining a two-dimensional position of the receiver relative to a detected light, or can have a three-dimensional spot collimating lens and charged couple device optical detector for determining a three-dimensional position of the receiver relative to a detected light. The receiver and lights can be synchronized for converting a delay time into a distance measurement to calculate a distance between a light and the receiver.

Abstract: Disclosed are systems and methods for improving communication in an optical communication system having spectrally shaped pulses. Embodiments of the systems and methods include sending a first spectrally shaped pulse over a channel connecting a transmitter and a receiver. Then, comparing the spectrally shaped pulse received at the receiver to a predetermined spectrally shaped pulse. The systems and methods further include obtaining a preemphasis coefficient that describes the difference between the spectrally shaped pulse received at the receiver to the predetermined spectrally shaped pulse by utilizing a mathematical description of C(&ohgr;k)e j(&ggr;&bgr;(&ohgr;k)) and multiplying a second spectrally shaped pulse with the preemphasis coefficient before sending the second spectrally shaped pulse to the receiver.

Abstract: A free space optical interconnect system tolerant to misalignments and utilizing redundant elements of a transmitter and/or a receiver is provided. The elements are arranged into clusters, the number of clusters being redundant, and the number of elements in each cluster being sufficient to accommodate the number of data channels to be transmitted. The system also includes means for identifying misalignments between the transmitter and the corresponding receiver, including means for providing feedback between the transmitter and the receiver regarding the misalignment, and means for re-routing data from the cluster which is misaligned to the redundant cluster which thus redirects data to/from the correct physical location. Preferably, the elements are arranged into one-dimensional or two-dimensional arrays, the elements of the transmitter being optical emitters or optical modulators. Uni-direction and bi-directional link systems are implemented in various embodiments of the invention.

Abstract: The invention concerns a method of establishing and/or maintaining a wake mode in an electrical installation, which in addition to at least one receiving device has at least one transmitting device that is connected through an optical bus system. So as not to always have to operate the different devices in the stand-by mode when no data traffic takes place through the optical bus system, the state of the art proposes activating the receiving device only part of the time. If during that time the receiving device receives a corresponding signal from the transmitting device, the stand-by mode is ended in order to establish the data exchange. However this operating mode is also disadvantageous because of the power consumption.

Abstract: Devices for providing optical signal transmissions between a transmitter unit and a receiving unit which is mobile relative to the transmitter unit. The units are optically coupled to each other via an optical transfer medium, and thus improve transmission quality by eliminating, or greatly reducing interferences that affect the transmission quality.

Abstract: The optical wireless communication device 1 is provided with a transmitting unit 102 outputting a light such as a laser light for optical communication. Beside the transmitting unit 102, the optical wireless communication device 1 is also provided with a laser pointer 24 emitting a light for optical axis adjustment. Further, the front surface of the optical wireless communication device 1 has a sight 401 where a light for an optical axis adjustment irradiates to allow proper adjustment of an optical axis. The optical wireless communication device 1 allows optical axis adjustment to be quick and easy in the configuration where a position of a device of one side is adjusted for an optical axis alignment with the device of the other side by checking the lighting of the LED 22 in the other side.

Abstract: A combat IFF system, for use in a combat exercise or on the battlefield, including a helmet-mounted passive IFF response unit and a weapon-mounted IFF interrogatory unit for each soldier. Infrared (IR) signals are employed for both challenge and response. The IR response signal is a very narrowly-targeted reflection of the relatively narrow IR transmit signal, thereby minimizing interception opportunities. The transmit and response signals are encoded in a transaction that cannot be compromised even when either or both signals are intercepted and decoded by the enemy. The combat IFF system includes biometric anti-spoofing features that prevent any use by an enemy in possession of captured units. Military radio-frequency (RF) spectrum is not required so there are no bandwidth limitations on simultaneous IFF transactions in the battlefield. A combat IFF transaction is completed in milliseconds.

Abstract: The system for browsing objects in reality that enables a user to obtain information via a wireless browser-enabled device. The browser-enabled device includes a modulated laser that is directed toward target sensors located on or near objects for which information is sought by a user. The target sensors, in turn, relay information as well as information received from the modulated laser via Internet to a wireless network that serves the browser-enabled device of the user. Information concerning the object of interest is then relayed to the browser-enabled device allowing the user to view information concerning the object.