Abstract: A system reducing pixel-based spatial noise for an uncooled infrared imager includes a first step of subtracting the historical scene-based NUC offsets for each selected pixel calculated from the previous frame. A filtered image for output module output is calculated using an edge preserving smoothing filter. The edge preserving smoothing function consists of a plus-shaped median kernel in which selected pixels that differ from the center pixel by greater than a specified threshold are replaced with the center pixel. The result is subtracted from the center pixel forming a high pass, edge ignoring, version of the frame which is dominated by system noise. A low pass version of the noise frame is created with a 5×5 mean filter. This is subtracted from the initial noise frame to improve scene rejection. This high pass version of the image/noise frame is attenuated by a configurable value.

Abstract: A calibration assembly and system for collocated transceivers includes calibration logic that determines at least one calibration ratio based on the isolation between a transmitter and a receiver on a platform, such as an aerial vehicle, regardless of whether the vehicle is manned or unmanned. The calibration logic utilizes a power level of the signal of interest at the receiver to calibrate a power output level of a transmit signal transmitted from a transmit antenna of the transmitter based on calibration ratios stored in a database. The transmitter then transmits the transmit signal from the transmitter at a power level sufficiently low to prevent a ring-around or wraparound power level from exceeding the power level of the received signal of interest input to the receiver so as to not cause cosite or colocation interference in the receiver.

Abstract: A system and method that uses tunnelizing for analyzing frequency spectrum. The method may include the steps of under sampling an input signal to take samples in one or more tunnels each with a tunnel bandwidth that is equal to or less than a total analysis bandwidth of the input signal; detecting one or more cyclostationary features of the input signal based on the samples; and determining one or more signal types of the one or more cyclostationary features based on the one or more cyclostationary features.

Abstract: An object detection system uses a change in a linear polarization statistic between a first image at a first time and a second image at a second time to determine the presence or the likelihood of an object beneath a surface. The presence of the object may be determined by regions of anomalously high changes in the polarization statistic. The system may use a polarization change detection detector which may simultaneously capture images in multiple polarization channels. Further, the polarization change detection detector may be coupled with a laser interferometry system.

Abstract: The system and method for adaptively obtaining coefficients of an inverse model for both equalization and pre-distortion for a multi-channel and reconfigurable RF system. The system preforms real-time learning and adaption and does not require training sets. In some cases, the system learns new coefficients across time and transient changes in performance.

Abstract: An indicator assembly and method for detecting and indicating a Global Positioning System (GPS) signal error during testing or monitoring of a GPS enabled device. The assembly includes an azimuth-elevation servo system; a GPS receiver; and a microprocessor engaged with the GPS receiver and servo system. The microprocessor executes programming that compares an expected self-position solution of the indicator assembly with a reported-position solution of the indicator assembly provided by the GPS receiver. The microprocessor activates the servo system to move a visually-observable indicator device to a position that reflects results of the comparison between the expected and reported position solutions. An operator noting unexpected behavior in the GPS enabled device checks the position of the indicator device and determines that a GPS signal error has occurred when the indicator device is oriented at any angle other than ninety degrees relative to a surface upon which the indicator assembly rests.

Abstract: A frequency multiplier, which may include multiple commutator cells, for multiplying an input signal is provided. A frequency doubler is provided that includes at least one transformer. Each of the at least one transformer includes a primary and a secondary. Each secondary includes a center tap. The frequency doubler further includes at least one commutator cell. Each of the at least one commutator cell includes a first differential pair of input terminals and a second differential pair of input terminals. Each primary is connected to the first pair of differential input terminals and each secondary is connected to the second differential pair of input terminals. The frequency doubler further includes at least one current source and at least one ground. The center tap is connected to the at least one ground via the at least one current source.

Abstract: An object detection system uses a change in a linear polarization statistic between a first image at a first time and a second image at a second time to determine the presence or the likelihood of an object beneath a surface. The presence of the object may be determined by regions of anomalously high changes in the polarization statistic. The system may use a polarization change detection detector which may simultaneously capture images in multiple polarization channels. Further, the polarization change detection detector may be coupled with a laser interferometry system.

Abstract: An orthoscopic, apochromatic lens is suitable for deployment such as on aerial platforms provides distortion less than 0.2% over a full field of view of more than 60° with F# less than 6.5 and focal length greater than 3?, and in embodiments greater than 5?. Embodiments are apochromatic from 500 to 950 nm to within 7 microns. Embodiments have an overall length of less than 7?. The lens includes five optical groups with an aperture stop between the second and third groups. The optical groups have one, one, two, one and one optical element each, as ordered from the object to the image plane, and have positive, negative, positive, positive, and negative optical powers, respectively. Embodiments are telephoto. In embodiments the focal length is temperature invariant within 0.0015 inches from 0° C. to 40° C.

Abstract: A compander including a module configured to compress a range of amplitudes of a signal in accordance with a companding function derived using a calculus of variations approach and method for deriving the companding function.

Abstract: An F-theta lens provides more than 88 degrees FFOV, F #2.8 or less, length not more than 200 mm, and/or 2.5 ?m or better resolution, with color correction from 450 nm to 650 nm. The lens includes three optical groups having positive, negative, and positive optical powers respectively, which can include four, four, and six elements, respectively. Embodiments include an aperture stop in the center of the second optical group. Refractive indices and ray heights are selected to correct for field curvature. Embodiments further include a CMOS detector having pixel pitch of 1.25 microns or less, density of 18 megapixels or more, focal plane diameter of 57.2 mm or more, Nyquist sampling of 400 lines per mm or more and wide pixel field of view of 30° or more. A plurality of CMOS detectors can be arrayed to create a mosaic image.

Abstract: A light sensing apparatus includes: an arrangement of light sensing pixels, one or more pixels each associated with a noise floor and able to detect a triggering level of incoming light above the noise floor from a corresponding portion of a scene; readout circuitry to process and reset the triggering pixels; and an automatic gain control (AGC) to raise the noise floor of one or more pixels. Sometimes, the light sensing apparatus is part of a seeker that includes control circuitry to dynamically control the AGC to raise the noise floor of one or more pixels by an adjustable amount that varies in relation to the distance between the seeker and an intended target. Sometimes, the control circuitry dynamically controls the AGC in response to a concurrent triggering of two or more triggering pixels. or in response to a gain schedule corresponding to guiding the seeker to the intended target.

Abstract: A method and system of reliably detecting a reactive jamming attack and estimating the jammer's listening interval for exploitation by a communication system comprises channelizing one or more signals of interest (SOI), channelizing one or more signals of unknown origin (SUO), identifying frequency support patterns for the SOI and SUO using Bayes thresholds, comparing SOI and SUO detection map histories, and determining a percent match, where a match percentage above a specified minimum indicates a reactive attack. Edge detection can be used to enhance jammer support. Embodiments further detect reactive jammer adaptation to changes in the SOI's frequency support. Embodiments include detectors that are insensitive to jammer modulation and/or signal type. A jammer reaction delay and/or size and periodicity of receive window can be detected. Embodiments determine if a jammer is copying and retransmitting the SOI's waveform(s), and/or if the jammer is anticipatory.

Abstract: A seeker includes a detection array having at least 2500 sensing pixels arranged in rows by row request lines and in columns by column request lines. At least one pixel includes an electromagnetic radiation sensor to trigger the pixel in response to sensing a triggering quantity of electromagnetic radiation, a row request circuit to send a row request after the pixel triggers, and a column request circuit to send a column request after the pixel triggers. The seeker further includes a row receiver to receive the row requests, a column receiver to receive the column requests, and a sequencer to receive, for each triggering pixel, the row of the row request and the column of the column request, and to generate an event including the received row and column of the pixel. The seeker also includes a time stamper to generate a time stamp for the generated event.

Abstract: A more robust universal asynchronous receiver-transmitter (UART) protocol utilizing a pattern matching methodology to evaluate and decode a serial data stream in noisy environments is provided. The UART protocol is may further allow for adjustment of the expected edge of a data bit within the serial data stream to reduce and/or eliminate drift in the data stream.

Abstract: A more robust universal asynchronous receiver-transmitter (UART) protocol utilizing a pattern matching methodology to evaluate and decode a serial data stream in noisy environments is provided. The UART protocol is may further allow for adjustment of the expected edge of a data bit within the serial data stream to reduce and/or eliminate drift in the data stream.

Abstract: A process of screening direction finding solutions to reduce the number of valid direction finding solution rejections while maintaining an acceptable level of wild bearings being reported utilizing the proximity of the correlation values of the highest correlation and second highest correlation given a correlation pattern of a detected signal of unknown origin.

Abstract: An antenna receiver has antenna elements that are arranged in an array and spaced apart from each other at a distance greater than one-half wavelength of the highest operating frequency of a signal that is to be detected by the antenna receiver. The antenna receiver has geolocation logic that uses the inter-element phase difference measurements to obtain a location of the signal source. The change in the inter-element phase differences enables the elements to be spaced apart at great distances, which is beneficial for the physical construction of the platform, as the elements may be easily placed at convenient locations for conformal aerodynamic properties.

Abstract: A zero knowledge communications protocol is provided that can unconditionally secure communications sent through a communications network by encrypting all messages, continuously sending noise messages through the network, and routing all network activity through an anonymity network. This combination of components prevent an eavesdropper on the network from garnering any information about when a communication is sent, the contents and statistics of a communication, the sender, or the intended recipient of the communication.

Abstract: A method for detection and identification of a chemical using a preconcentrator to collect a sample of the chemical, process said sample of the chemical, and introduce said processed chemical into a chemical analysis instrument for the detection of and identification of the chemical. A system for detecting and identifying a chemical comprising a preconcentrator having at least dual concentrating elements.