Abstract: A system for disrupting Radio Frequency communication of a plurality of unmanned aircraft. The system comprises: a directional antenna; a transmitter; a drive system connected to the directional antenna and configured to move the directional antenna; and a control system. The control system causes the transmitter to generate a signal waveform configured to disrupt Radio Frequency communication of an unmanned aircraft for emission by the directional antenna, and causes the drive system to move the directional antenna such that each of the plurality of unmanned aircraft is irradiated intermittently by the emitted radiation. Each of the plurality of unmanned aircraft is irradiated for a first period of time and not irradiated for a second period of time, the second period of time is less than or equal to 5 seconds.

Abstract: Methods and apparatus for interference cancelation in a radio frequency communications device are described. In various embodiments a signal to be transmitted in converted into an optical signal and processed using an optical filter assembly including one or more optical filters to generate an optical interference cancelation signal. The optical interference cancelation signal is converted into an analog radio frequency interference cancelation signal using an optical to electrical converter prior to the analog radio frequency interference cancelation signal being combined with a received signal to cancel interference, e.g., self interference. The optical filter assembly can include a large number of taps, e.g., 30, 50, 100 or more. Each tap may be implemented as a separate optical filter or series of optical filters. Delays and/or gain of the optical filters can be controlled dynamically based on channel estimates which may change due to changes in the environment and/or communications device position.

Abstract: An electronic device and communication method are disclosed. The electronic device comprises a processing circuit configured to perform a pre-processing operation on a first one-dimensional sequence of modulation symbols, the pre-processing operation including: performing a dimension-increasing conversion to convert the first one-dimensional sequence of modulation symbols into a first multi-dimensional modulation symbol block; transforming the first multi-dimensional modulation symbol block into a second multi-dimensional modulation symbol block with a first transformation, wherein the first transformation couples each symbol in the first multi-dimensional modulation symbol block with each other; and performing a dimension-decreasing conversion to convert the second multi-dimensional modulation symbol block into a second one-dimensional sequence of modulation symbols, wherein the dimension-decreasing conversion is an inverse process of the dimension-increasing conversion.

Abstract: A method of RF signal processing comprises receiving an incoming RF signal at each of a plurality of antenna elements that are arranged in a first pattern. The received RF signals from each of the plurality of antenna elements are modulated onto an optical carrier to generate a plurality of modulated signals that each have at least one sideband. The modulated signals are directed along a corresponding plurality of optical channels with outputs arranged in a second pattern corresponding to the first pattern. A composite optical signal is formed using light emanating from the outputs of the plurality of optical channels. Non-spatial information contained in at least one of the received RF signals is extracted from the composite signal.

Abstract: Aspects of the present disclosure describe large scale steerable optical switched arrays that may be fabricated on a common substrate including many thousands or more emitters that may be arranged in a curved pattern at the focal plane of a lens thereby allowing the directional control of emitted light and selective reception of reflected light suitable for use in imaging, ranging, and sensing applications including accident avoidance.

Abstract: The invention provides an optical module which is less likely to be damaged, and can be assembled at low cost. The optical module comprises a housing having an electrical signal port for inputting and/or outputting an electrical signal and an optical signal port for inputting and/or outputting an optical signal, a first substrate arranged in the housing so as to connect to the electrical signal port, an optical fiber arranged in the housing so as to connect to the optical signal port, and a second substrate provided with an optical device which connects to the optical fiber to input the optical signal from the optical fiber and output the optical signal to the optical fiber, and arranged in the housing so as to electrically connect to the first substrate, and to be inclined with respect to a base plane of the housing.

Abstract: Methods and apparatus for interference cancelation in a radio frequency communications device are described. In various embodiments a signal to be transmitted in converted into an optical signal and processed using an optical filter assembly including one or more optical filters to generate an optical interference cancelation signal. The optical interference cancelation signal is converted into an analog radio frequency interference cancelation signal using an optical to electrical converter prior to the analog radio frequency interference cancelation signal being combined with a received signal to cancel interference, e.g., self interference. The optical filter assembly can include a large number of taps, e.g., 30, 50, 100 or more. Each tap may be implemented as a separate optical filter or series of optical filters. Delays and/or gain of the optical filters can be controlled dynamically based on channel estimates which may change due to changes in the environment and/or communications device position.

Abstract: A method of transmitting optical signals in a submarine optical network and an optical unit for performing the method, the optical unit is configured for receiving an optical signal comprising a plurality of wavelengths where at least some of the wavelengths comprise traffic data. The optical unit includes a processor unit which is configured for scrambling the shape of at least one wavelength comprising traffic data of the optical signal so as to make said traffic data of said at least one wavelength undetectable for a receiver station.

Abstract: Various embodiments of the present invention relate to pre-jam waveforms for enhanced optical break lock jamming effects. In various examples, pre-jam waveforms for enhanced optical break lock jamming effects may be implemented in the context of systems, methods, computer program products and/or algorithms.

Abstract: A method for operating a pulsed interference laser in an eye-safe manner in a DIRCM system onboard an aircraft is provided. A reception apparatus is used to receive echoes from the emitted pulses from the interference laser and to evaluate them to determine whether an object is situated within a prescribed laser safety distance for the DIRCM system in the laser beam. The emission of the laser beam is enabled separately for a respective period of time ?t within the period of use of the interference laser, the emission being enabled for the respective subsequent period of time ?t only if no object has been found within the laser safety distance within the respective preceding period of time ?t.

Abstract: According to a first aspect, a method of controlling an electronic system includes the step of receiving by a first device a plurality of receivable wireless signals that are intended to control functions of a second device. The first device transmits a wireless signal that prevents a subset of the plurality of receivable wireless signals from controlling the second device.

Abstract: Various embodiments of the present invention relate to weighted waveforms for improved jam code effectiveness. In various examples, weighted waveforms for improved jam code effectiveness may be implemented in the context of systems, methods, computer program products and/or algorithms.

Abstract: A system is disclosed to identify authorized EO devices and unauthorized EO devices within a scene. The system hampers the operation of the unauthorized EO devices detected within the scene.

Abstract: The first photon in single-photon state is divided into two components by the half beam splitter, and the first component is sent to the sender while the second component is sent to the receiver. The sender measures the first component of the first photon when he sends “1”. The sender doesn't measure the first component of the first photon when he sends “0”. The receiver makes the second component of the first photon enter into the Sagnac interferometer, and the receiver also makes the reference light enter into the Sagnac interferometer at the same time. The receiver makes the second component of the first photon interact with the reference light in the nonlinear optical medium arranged in the Sagnac interferometer. The receiver knows the signal from the phase modulation of the reference light caused by the interaction with the second component of the first photon.

Abstract: Various embodiments provide secure optical transmission of data. Noise may be added to optical signals transmitted by spatial paths of a multimode optical fiber. The noise may be added electrically prior to modulation, or optically after modulation. In some embodiments a transmitter and a receiver cooperate to maintain a noise level sufficient to place a tapped signal in a noise regime that provides a predetermined level of data security.

Abstract: A laser jammer configured for being a part of a countermeasure system. The system comprises a stage having an axis of rotation and laser source mounted on the stage. The laser source is configured for emitting a laser beam having an optical axis perpendicular to the axis of rotation. The laser has a first spread in a first plane parallel to the rotation axis of the stage and including the optical axis, and a second spread in a second plane perpendicular to the first plane and including the optical axis. The first spread is greater than the second spread.

Abstract: Embodiments of the invention provide systems and methods for deactivating reactive jamming attacks and other sophisticated attacks in wireless sensor networks (WSNs). In one system, trigger nodes (nodes whose transmissions invoke jammer nodes) are identified and communications between the sensor nodes of the WSN are routed to avoid sending (e.g., transmitting) information from identified trigger nodes. For example, identified trigger nodes are routed as receivers only. One method of identification uses an advanced randomized error-tolerant non-adaptive group testing technique and a clique-independent set problem solution. Another method of identification uses a hexagon tiling coloring and sequential group testing scheme.

Abstract: The invention concerns a device for countering and tracking a threat in the form of a homing-head missile, comprising a homing head adapted to receive an incident coherent light beam and to deflect same to produce a transmitted beam. The invention is characterized in that the homing head comprises a biprism including two prisms made of different materials and adapted to divide the transmitted beam into two sub-beams, the refractive index difference between the prisms being adapted to introduce an optical path difference between the two sub-beams which is greater than the coherence length of the incident beam.

Abstract: An interference cancellation system (ICS) may be used with a communication system to prevent or minimize interference from one or more sources. The ICS may receive radio RF signals comprised of one or more signals of interest (SOI) and multiple interfering signals. The ICS may use a sample of the interfering signals to cancel the interfering signals from the SOI. The multiple interfering signals may be converted into a single optical signal for cancellation. One or more optical cancellation paths may be used for interference cancellation. Each optical cancellation path may include an optical attenuator and/or an optical delay to achieve phase shifts and/or delays for interference cancellation.

Abstract: A system is disclosed to identify authorized EO devices and unauthorized EO devices within a scene. The system hampers the operation of the unauthorized EO devices detected within the scene.

Abstract: A countermeasure device for directing a mobile tracking device away from an asset is provided. The countermeasure device includes a continuous wave laser source whose output is directed at a seeker head of the mobile tracking device. The countermeasure device causes the generation of localized sources within the mobile tracking device and confuses the mobile tracking device as to the true location of the asset.

Abstract: In one embodiment, the optical transport system has an optical transmitter, an optical receiver, and one or more phase-sensitive amplifiers (PSAs) disposed within an optical link that connects the optical transmitter and receiver. The optical transmitter employs a first nonlinear optical process to generate a two-carrier signal in a manner that makes this signal suitable for phase-sensitive amplification. The PSAs employ a second nonlinear optical process to optically amplify the two-carrier signal in a phase-sensitive manner to counteract the attenuation imposed onto the two-carrier signal by lossy components of the optical link. The optical receiver employs a third nonlinear optical process in a manner that enables the receiver to beneficially use redundancies in the two-carrier signal, e.g., for an SNR gain.

Abstract: Receivers and methods are provided for polarization mode dispersion compensation in multi-level coded-modulation schemes using a BLAST algorithm and iterative polarization cancellation. A receiver includes a vertical Bell Laboratories Layered Space-Time Architecture (V-BLAST) orthogonal frequency division multiplexing (OFDM) detector configured to receive input sequences and partially cancel polarization interference with respect to the input sequences to output symbol estimates for the input sequences. The receiver further includes one or more low-density parity-check (LDPC) decoders coupled to the V-BLAST OFDM detector configured to receive channel bit reliabilities and output code words. The channel bit reliabilities are indirectly calculated from the symbol estimates. The one or more LDPC decoders iteratively provide extrinsic soft information feedback to the V-BLAST OFDM detector to compensate for the polarization interference.

Abstract: An optical impact system controls munitions termination through sensing proximity to a target and preventing effects of countermeasures on false munitions termination. Embodiments can be implemented on in a variety of munitions such as small and mid caliber that can be applicable in non-lethal weapons and in weapons of high lethality with airburst capability for example and in guided air-to-ground and cruise missiles. Embodiments can improve accuracy, reliability and lethality of munitions depending on its designation without modification in a weapon itself and make the weapon resistant to optical countermeasures.

Abstract: A modulation device provides optical energy to hamper the operation of a mobile tracking device. The optical energy may include multiple mobile device specific optical codes directed at the mobile tracking device in parallel.

Abstract: An embodiment of a method and apparatus for determining a change in network-generated crosstalk levels caused by a multi-line phone includes determining a first crosstalk level between a first line pair and a second line pair of a multi-line phone caused by the multi-line phone, and determining a second crosstalk level between each of the first line pair and the second line pair of the multi-line phone. The second crosstalk level is determined when the first line pair and the second line pair are coupled to a first predetermined length of network line pair cable. The method further includes determining a change of network generated crosstalk levels caused by the multi-line phone by subtracting the first crosstalk level from the second crosstalk level.

Abstract: Radio frequency transmission systems often suffer from the problem of co-site interference, where the frequency band of a strong radio transmitter overlaps with the frequency band of a co-located and/or remote radio receiver, such that the transmitter interferes with the ability of the receiver to detect a weak signal of interest. There is a need for a device that can process both the transmitted radio signal and the received radio signal to eliminate such interference. Previous attempts to solve this problem have been unable to cancel in-band interference in excess of 20 to 40 dB stronger than the signal of interest over a broad bandwidth, with large dynamic range, and with a high degree of linearity. Disclosed is a robust system and method for cancelling broadband in-band RF interference that operates in a dynamically changing multipath environment.

Abstract: A countermeasure device for directing a mobile tracking device away from an asset is provided. The countermeasure device includes a continuous wave laser source whose output is directed at a seeker head of the mobile tracking device. The countermeasure device causes the generation of localized sources within the mobile tracking device and confuses the mobile tracking device as to the true location of the asset.

Abstract: An optical telecommunications network terminal includes a device for generating downlink optical signals and a device for receiving uplink optical signals, the optical signals being conveyed in optical transmission means connected to the terminal. More particularly, the generator device is adapted to generate a continuous optical signal at wavelength ?ii and having an initial power greater than a power threshold for the occurrence of a stimulated Brillouin effect, above which threshold said continuous optical signal induces in the optical transmission means a continuous Brillouin backscattering uplink optical signal at wavelength ??ii. The optical signal receiver device further includes means for analyzing the power of said continuous Brillouin backscattering optical signal at wavelength ??ii.

Abstract: In an IR jamming system for defense against missiles with IR-sensitive homing heads, one or more jamming beams are generated, whose diameter is less than that of the optical aperture of the IR-sensitive homing head of the missile. The optical aperture of the IR-sensitive homing head of the missile is at least partially illuminated by the jamming beam or beams.

Abstract: An optical linear feedback circuit has an optical loop delay path (10) for recirculating a sequence of optical signals, and an output path for outputting delayed optical signals after circulating one or more times around the loop. A selector (50) is provided for selecting one or more of the delayed optical signals from the sequence, and an optical logic circuit (20) is coupled to carry out a logical operation on the selected delayed optical signals to create an optical feedback signal which is coupled to the optical loop delay path, so that the optical feedback signal can be added to the sequence of optical signals already circulating. By recirculating around a loop, each round trip can be regarded as equivalent to a shift of a shift register, so longer sequences can be built up without needing an additional storage cell for each shift function.

Abstract: Direct generation semiconductor infrared countermeasure lasers are provided that can be independently modulated and combined so as to provide a simultaneously-generated multi-spectral output for the beam. The countermeasure system is smaller and more lightweight than conventional IRCM laser systems, is less expensive, is non-cryogenically cooled and is configurable for multi-spectral generation with asynchronous jam codes in which the spectral distribution can be customized by combining multiple emitters with a range of center wavelengths.

Abstract: A technique for securing data transmission via an optical communication line comprising an optical fiber extending between a first network element and a second network element; the technique comprises conveying a first optical signal carrying data via the optical fiber from the first network element towards the second network element at a predetermined optical wavelength, and conveying a second optical signal at the same predetermined optical wavelength via the same fiber in the opposite direction to create within the optical fiber a combined optical signal such that combination of the first and second optical signals is adapted to hamper an unauthorized non-intrusive extraction of the first optical signal from the combined optical signal.

Abstract: An image-reading device includes a linear image sensor and a cable. The linear image sensor is divided into, at least, first, second and third blocks. The first block is disposed adjacent to the second block. Each block reads images on an original document and generates image signals. The cable includes, at least, first, second and third signal wires corresponding to the first, second and third blocks respectively. Each signal wire transmits the image signals generated by each block. The third wire is sandwiched between the first signal wire and the second signal wire.

Abstract: Data is encrypted onto an electromagnetic beam by providing an electromagnetic beam having a signal component having a modal state, wherein the signal component is susceptible to accumulation of a geometric phase, and a reference component, transmitted along a path over at least part of which the signal component accumulates a geometric phase by transformation of its modal state from a first to a second modal state, from the second to at least one further modal state, and then back to the first modal state; and modulating with the data the geometric phase so accumulated, by modulating the modal state transformations. Data is decrypted from a received electromagnetic beam by corresponding processing of the received electromagnetic beam and by comparing an overall phase of the signal component with an overall phase of the reference component so as to retrieve the modulation.

Abstract: A quantum repeater includes a transmitter portion including a source, a set of matter systems, and an optical system. The source produces a probe pulse in a probe state having components with different photon numbers, and each matter system has at least one state that interacts with photons in the probe pulse to introduce a change in a phase space location of the probe state. The optical system can direct the probe pulse for interaction with one of the matter systems and direct light from the matter system for transmission on a first channel.

Abstract: A method for operating a pulsed interference laser in an eye-safe manner in a DIRCM system onboard an aircraft is provided. A reception apparatus is used to receive echoes from the emitted pulses from the interference laser and to evaluate them to determine whether an object is situated within a prescribed laser safety distance for the DIRCM system in the laser beam. The emission of the laser beam is enabled separately for a respective period of time ?t within the period of use of the interference laser, the emission being enabled for the respective subsequent period of time ?t only if no object has been found within the laser safety distance within the respective preceding period of time ?t.

Abstract: In various embodiments, a secure optical communication system is disclosed. Such a system may include a photon-pair generation circuit configured to generate pairs of photons with each photon pair including a first-channel photon and a second-channel photon, a transmitting circuit configured to receive first-channel photons, and modulate the first-channel photons according to a stream of data using a first optical circulator to produce first-modulated photons, and a receiving circuit configured to receive second-channel photons, pass the second-channel photons through a complementary optical circulator to produce second modulated photons, and detect relative timing between the first-modulated photons and the second modulated photons to recover the stream of data.

Abstract: Narrow-band interference in spread spectrum systems is eliminated by performing a frequency spectrum transform on N sampling points of the data to obtain N points of data; after M transforms, getting an energy accumulation of individual data to obtain N energy values; removing partial excessive large values from the N energy values, averaging the rest, then calculating the threshold value for interference determination based on the average value; identifying all points that have energy values exceeding the threshold value, and performing interference suppression for the data of corresponding points after frequency spectrum transform and finally outputting the data after frequency spectrum inverse transform.

Abstract: A bidirectional optoelectronic device comprises a photodetector, a light source, and a drive circuit for the light source. The light source has first and second electrical leads for receiving an input electrical signal, and the drive circuit can be arranged to apply first and second portions of the input electrical signal to the first and second electrical leads, respectively, wherein the second portion of the input electrical signal is a scaled, inverted substantial replica of the first portion of the input electrical signal. A protective encapsulant can be applied that includes hollow dielectric microspheres to reduce electrical cross-talk, and that can further include an optical absorber to reduce optical cross-talk. A waveguide substrate of the device can include light collector(s) or trap(s) for redirecting and attenuating portions of optical signals propagating in waveguide layers on the substrate but not guided by a waveguide.

Abstract: An electronic apparatus, e.g., a central signal unit for a vehicle, has a signal receiver which operates in the optical wavelength range for receiving signals of an external signal source, and an internal signal source for emitting signals which are different from signals of the external signal source, and which operates essentially in a wavelength range which is the same as or directly adjacent to the wavelength range of the external signal source. The signal receiver and the internal signal source are situated in the apparatus behind a reflective cover. The apparatus includes a suppression unit which prevents generation of interference signals at the signal receiver.

Abstract: The embodiments disclosed herein relate an insertable shield clip for use in controlling electromagnetic interference in an optical transceiver module. The optical transceiver module may include a shell that houses first and second optical subassemblies and an enclosure that cooperates with the shell in defining a covering for the optical transceiver module. The shield clip may comprise a body composed of conductive material. The body may include first and second vertical side members. The body may also include first and second shield members that are each configured to receive a corresponding nosepiece of one of the first and second optical subassemblies. The body may further include a bottom member that interconnects the first and second vertical side members and the first and second shield members.

Abstract: Photonic signals are tagged with a pre-selected modification, such as a polarization signature to carry data across an obstructed path between sender and receiver. Communication authentication through polarization variation allows for Yuen-Kumar or entangled photon quantum communication protocols to propagate through environmental scattering media such as air, smoke, fog, rain, and water. While ultraviolet light photons are well suited as a carrier for quantum communication signals scattered in air, it is appreciated that visible wavelengths have longer propagation paths in water to convey non-line-of-sight data. A secure signal is scattered by the media and simultaneously communicated to a single recipient or multiple recipients exposed to scattered signal portions. A process of solving the scattering processes through a random scattering media is provided to reconstruct a quantum keyed message at a receiver.

Abstract: An optical line terminal (OLT) performs power management control in a passive optical network (PON) by acquiring a respective reception level for each optical network unit (ONU) in the PON and maintaining a reception table that stores the respective reception level for each ONU. Prior to receiving a burst signal from an ONU, it sets a reception threshold of an optical receiver at the OLT with the reception level of the ONU.

Abstract: A missile or other weapons countermeasure system includes a non-directional, modulated laser energy signal designed to protect an object (such as an aircraft, land vehicle, building, or vessel). Once a potential threat has been detected, a laser energy source generates a laser energy signal of sufficient power to provide the necessary coverage. The laser energy is modulated using an oscillator to create the appropriate countermeasure signal. Next, fiber optics or other coupling device distribute the modulated laser energy signal to one or more apertures, preferably wide angle lenses or the like, disposed about the outer surface of the object to be protected. The number and location of the apertures will depend upon the circumstances of the installation as well as the desired coverage.

Abstract: The present invention provides a system, apparatus and method to improve the signal-to-noise ratio performance in receivers configured to receive differential data signals. According to various embodiments of the invention, a received differential signal is processed to consider both forward-looking and backward-looking error components to improve SNR performance, and ultimately the reach of the optical line system. Additional processing is provided to further enhance noise tolerance related to chromatic dispersion.

Abstract: A communications module includes an interior configuration designed to intercept, disrupt, and scatter EMI produced by the module during operation. The interior configuration may include an anechoic structure that includes a plurality of anechoic elements positioned proximate EMI-producing components within the module. The anechoic elements may form truncated pyramids, columns having rounded tops, cones, or other shapes. The anechoic elements may be uniform or non-uniform in size, length, or shape and can be arranged in a periodic, non-periodic, or random pattern. In some embodiments, the anechoic elements may include cast zinc metal, Nickel, and/or radiation absorbent material, such as a mixture of iron and carbon. In operation, EMI impinging on the anechoic elements is scattered by their surfaces until absorbed by the elements or other structures of the module, thereby preventing the EMI from exiting the module.

Abstract: An optical communication system is provided. In one embodiment, a source creates a multiplicity of photon pairs, with each photon pair comprising a first photon and a second photon. The first photon is sent to a transmitter, and either remains in the transmitter or is transmitted by the transmitter to a receiver. The second photon is sent to the receiver. Data is decoded by determining a polarization direction and a time of detection of any photon pairs detected at the receiver.

Abstract: The present invention relates to a laser based system for protecting a platform against an armament equipped with an optical homing head element, that includes a command and control assembly equipped with an interface to a detection and acquisition system that detects and locates a threatening armament and receives from it a warning about the detection of said threatening armament combined with data relating to it; and a laser source operable by the command and control assembly in order to produce the required energy for jamming the optical head of the threatening armament; and wherein the system is characterized by that it includes in addition a sectarian array of a plurality of end units that are connected unto the laser source for selectively routing laser energy from the source to an end unit that was selected by the command and control assembly as the end unit that is best suited under prevailing conditions for pointing at the threatening armament and attacking it by emitting a laser beam in its directio

Abstract: An embodiment of the present invention provides an apparatus, comprising a radio frequency identification transceiver adapted for self jammer suppression. The transceiver may further comprise a phase shifter and variable attenuator/variable amplifier adjusted to minimize the power injected into a receive chain by the self jammer. In an embodiment of the present invention the present transceiver may further comprise at least one RF peak power detector to determine the power injected into the receive chain.