Class / Patent application number | Description | Number of patent applications / Date published |
398039000 | INTERFERENCE SIGNAL TRANSMISSION OR ELIMINATION (E.G., JAMMING OR ANTIJAMMING) | 14 |
20090028557 | INSERTABLE EMI SHIELD CLIP FOR USE IN OPTICAL TRANSCEIVER MODULES - 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. | 01-29-2009 |
20090214205 | COMMUNICATIONS AND DATA LINK JAMMER INCORPORATING FIBER-OPTIC DELAY LINE TECHNOLOGY - A communications and data link jamming system employs a fiber-optic RF delay line to provide rapid responses to threat signals. A sample of the RF signal threat environment is stored within the delay line, and a jamming video signal is added to the stored sample by modulation as it is being extracted from the delay line. The extracted signal is re-circulated back into the delay line, thereby effectively stretching the sample for highly efficient jamming. The jamming system is effective in countering burst communications and in defeating multiple simultaneous threat signals. | 08-27-2009 |
20090297144 | POLARIZATION MODE DISPERSION COMPENSATION IN MULTILEVEL CODED-MODULATION SCHEMES USING BLAST ALGORITHM AND ITERATIVE POLARIZATION CANCELLATION - 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. | 12-03-2009 |
20100322623 | OPTICAL RECEIVER WITH IMPROVED NOISE TOLERANCE - 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. | 12-23-2010 |
20110262130 | ELECTRONIC APPARATUS HAVING MEANS FOR SUPPRESSING SIGNAL REFLECTIONS FROM AN INTERNAL SIGNAL SOURCE - 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. | 10-27-2011 |
20110311224 | Method for Operating a Pulsed Interference Laser in an Eye-Safe Manner in a DIRCM System - 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 Δt within the period of use of the interference laser, the emission being enabled for the respective subsequent period of time Δt only if no object has been found within the laser safety distance within the respective preceding period of time Δt. | 12-22-2011 |
20120213513 | Direct generation semiconductor IRCM laser system - 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. | 08-23-2012 |
20120219290 | OPTICAL LINEAR FEEDBACK CIRCUIT - An optical linear feedback circuit has an optical loop delay path ( | 08-30-2012 |
20120294608 | SYSTEM AND METHOD FOR BROADBAND RF INTERFERENCE CANCELLATION - 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. | 11-22-2012 |
20130071113 | OPTICAL TRANSPORT SYSTEM FOR TWO-CARRIER SIGNALS - 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. The optical transport system can advantageously be implemented to have better noise properties than a comparable conventional system, which enables a commensurate increase in the data-transport capacity. | 03-21-2013 |
20130308940 | MULTIPLE INTERFERER CANCELLATION FOR COMMUNICATIONS SYSTEMS - 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. | 11-21-2013 |
20140147116 | COUNTERMEASURE SYSTEM - 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. | 05-29-2014 |
20140186033 | SECURE DATA TRANSMISSION VIA SPATIALLY MULTIPLEXED OPTICAL SIGNALS - 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. | 07-03-2014 |
20140241716 | SCENE ILLUMINATOR - 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. | 08-28-2014 |