Abstract: A circuit and method are provided in which a six-transistor (6-T) SRAM memory cell is hardened to single-event upsets by adding isolation-field effect transistors (“iso-fets”) connected between the reference voltage Vdd and the field-effect transistors (“fets”) respectively corresponding to first and second inverters of the memory cell. According to certain embodiments, the control gates of first and second P-iso-fets are respectively tied to the control gates of first and second pull-up P-fets. According to certain embodiments, first and second N-iso-fets are connected between the output nodes of the memory cell and the pull-down N-fets respectively corresponding to the first and second inverters. The control gates of the first and second N-iso-fets are respectively tied to the control gates of the first and second pull-down N-fets. Again according to certain embodiments, one or more of the iso-fets are physically removed from the proximity of other transistors which comprise the memory cell.

Abstract: A monolithically integrated light-activated thyristor, in an n-p-n-p-n-p sequence consists of a four-layered thyristor structure and an embedded back-biased PN junction structure as a turn-off switching diode. The turn-off switching diode is formed through structured doping processes and/or depositions on a single semiconductor wafer so that it is integrated monolithically without any external device or semiconductor materials. The thyristor can be switching on and off optically by two discrete light beams illuminated on separated openings of electrodes on the top surface of a semiconductor body. The carrier injection of the turning on process is achieved by illuminating the bulk of the thyristor with a high level light through the first aperture over the cathode to create high density charge carriers serving as the gate current injection and to electrically short the emitter and drift layer.

Abstract: A system and method for generating target area information. The system comprises a first processor effective to receive first information of a first classification level and a second processor effective to receive second information of a second classification level distinct from the first classification level. A cross domain processor is in communication with the first and second processors. The second processor is effective to receive a request from a requesting entity about a region of interest and interrogate a first sensor regarding the request. The second processor is further effective to receive first information from the first sensor and send the request through the cross domain processor to the first processor. The first processor is effective to interrogate a second sensor regarding the request and receive second information from the second sensor.

Abstract: A circuit and method are provided in which a six-transistor (6-T) SRAM memory cell is hardened to single-event upsets by adding isolation-field effect transistors (“iso-fets”) connected between the reference voltage Vdd and the field-effect transistors (“fets”) respectively corresponding to first and second inverters of the memory cell. According to certain embodiments, the control gates of first and second P-iso-fets are respectively tied to the control gates of first and second pull-up P-fets. According to certain embodiments, first and second N-iso-fets are connected between the output nodes of the memory cell and the pull-down N-fets respectively corresponding to the first and second inverters. The control gates of the first and second N-iso-fets are respectively tied to the control gates of the first and second pull-down N-fets. Again according to certain embodiments, one or more of the iso-fets are physically removed from the proximity of other transistors which comprise the memory cell.

Abstract: A MMIC amplifier is directly connected to the balanced feed points at the aperture of an antenna to eliminate the distance between electronics coupled to the antenna and the antenna itself, such that interfaces, components and connection lines which introduce losses and parasitic effects that degrade system performance are eliminated due the direct connection. Expanding the aperture of the antenna to accommodate the direct connection of a MMIC amplifier to balanced feed points of an antenna has been found to have no deleterious effects on antenna performance. Moreover, when coupling the MMIC amplifier to an unbalanced coaxial line, any associated ripple is minimized due to the direct connection.

Abstract: A Gilbert cell mixer design is disclosed. Instead of using a differential transconductance stage as typically done, the design employs a differential transimpedance amplifier input stage. By utilizing a transimpedance input stage to the Gilbert mixer, feedback is used to obtain higher linearity without sacrificing noise performance. The transimpedance input stage supplies a current signal to the cascode connected Gilbert switching quad, so the transimpedance amplifier output is taken from the collector of the transimpedance amplifier output transistor, instead of the emitter as normally done with transimpedance amplifiers.

Abstract: In the method for processing a signal light from free-space by amplifying said signal for free-space optical communications, wherein the improvement includes the steps of (a) pre-amplifying said signal light with low noise; and (b) coupling said signal light into a multimode filter which reduces coupling losses compared to single mode filters.

Abstract: Techniques are disclosed that allow for the detection, identification, direction finding, and geolocation of emergency personnel in a given multipath environment. For example, the techniques can be used to detect and identify multiple lines of bearing (LOBs) to an IEEE 802.11 emitter of an emergency responder that is inside a building or otherwise hidden from view. LOBs from multiple vantage points can be used to geolocate and/or track the emergency responder. The resulting geolocation can be plotted on a map display or model of the scene (e.g., building, etc) so the precise position of the emergency responder having the targeted wireless emitter can be known.

Abstract: Techniques are disclosed that allow for the detection, identification, and direction finding of wireless emitters in a given multipath environment. For example, the techniques can be used to detect and identify a line of bearing (LOB) to an IEEE 802.11 emitter in a building or in an open field or along a roadside. In some cases, multiple LOBs can be used to geolocate the target emitter if so desired. The techniques can be embodied, for instance, in a handheld device that can survey the target environment, detect an IEEE 802.11 emitter and identify it by MAC address, and then precisely determine the LOB to that emitter. In some cases, a sample array of response data from the target emitter is correlated to a plurality of calibrated arrays having known azimuths to determine the LOB to the target emitter.

Abstract: Techniques are disclosed for detecting, identifying, and/or geolocating RF communications devices, such as FRS radios, high-power cordless phones, cellular phones, and other wireless communications receiver devices. The techniques exploit a vulnerability present in such devices, and can be used to detect (e.g., up to 300 meters) and geolocate (e.g., within ±3 meters) those devices. The vulnerability is that receiver circuitry of the target devices emanate RF mixing products when flooded with RF energy or suitable stimulus signal. Such a response to a stimulus signal is unexpected or otherwise unintentional, as receiver circuitry is generally not designed to transmit information. The RF frequency, phase, and amplitude of these sideband RF responses can be used to detect and location the devices. The techniques work in the presence of interference, and can be used on devices that are powered on or off.

Abstract: Techniques are disclosed that allow for the detection, identification, direction finding, and geolocation of wireless emitters in a given multipath environment. For example, the techniques can be used to detect and identify a line of bearing (LOB) to an IEEE 802.11 emitter in a building or in an open field or along a roadside. Multiple LOBs computed from different geographic locations can be used to geolocate the target emitter. The techniques can be embodied, for instance, in a vehicle-based device that can survey the target environment, detect an IEEE 802.11 emitter and identify it by MAC address, and then determine various LOBs to that emitter to geolocate the emitter. In some cases, a sample array of response data from the target emitter is correlated to a plurality of calibrated arrays having known azimuths to determine the LOB to the target emitter.

Abstract: A wireless communications network comprising a plurality of nodes and effective to provide quality of service requirements for packets being transmitted. An ingress node calculates variables based on quality of service requirements and places those variables in a header of a packet to be transmitted. The packet is then transmitted to a core node. The core node reads the variables in the packet and calculates a holding time for the packet based on the variables and the quality of service requirements.

Abstract: An orientation-independent antenna presents a circular polarization characteristic to incoming waves such that these waves are detected regardless or polarization and angle of arrival. The antenna includes crossed vertical loops and a horizontal loop, with the loops being phased to provide the circular polarization characteristic. In one embodiment, the antenna includes a number of elements on the faces of a cube, or the elements are positioned on the surface of a sphere. In another embodiment, the antenna is given both a right hand circular polarization characteristic and a left hand circular polarization characteristic in two different channels to provide for double the data throughput.

Abstract: An antenna comprising a crossed pair of center-fed end-loaded bent-dipole radiators which are structurally embedded into a properly loaded cavity. Broadband, dual independent polarized, and hemisphere field-of-view coverage with low RCS characteristics is provided with this antenna.

Abstract: One embodiment of the present invention provides a system for the transmission of data between an optical bus and an electronic component at a speed independent from a clock speed of the electrical component; the system comprising an optical data storage component communicating with both the optical bus and the electrical component; the optical data storage component being configured to hold data transmitted on the optical bus until said electrical component is available.

Abstract: A flat panel antenna used at a wall in a through-the-wall CW radar application is spaced from the wall by a half wavelength to eliminate the effects of energy reflected by the wall back to the antenna. In one embodiment, a ½-wavelength dielectric absorbing material insert is placed adjacent the flat panel antenna, which allows the flat panel antenna to be pressed against the wall for antenna stabilization, with the index of refraction of the material desirably being 3.

Abstract: A miniature conformal antenna is provided with a polarization-independent output by using quadrature elements at the mouth of a cavity and by processing the RHCP and LHCP outputs of the elements to arrive at a polarization-dependent solution; and then correcting the angle of arrival result by electronically rotating the antenna, measuring the amplitude difference between element pairs at various angles, generating an amplitude difference curve and deriving an angular correction factor therefrom.

Abstract: An imaging system configured with readout circuit redundancy is disclosed. Pixel data from a particular column can be steered around a defective readout circuit to an operational readout circuit. Thus, larger imaging arrays which are generally more prone to common column circuitry defects are enabled. In addition, imaging systems configured with significant on-chip signal processing, which are also more prone to common column circuitry defects, are enabled. The occurrence of lost pixel data from an entire column is eliminated or otherwise reduced, thereby increasing overall operability and yield of the imaging system. The system can be implemented on a single chip or a chip set.

Abstract: A digital to analog converter (DAC) method and apparatus employs a multiplying-adding DAC, eliminating digital adder circuitry. Examples are given for multiplying a 3-bit binary number by a 2-bit binary number; however, there are no limitations to the bit-widths of the numbers to be multiplied. The multiplying-adding DAC method can be scaled up or down in bit-width by feeding the DAC with partial sums and adjusting the DAC weights accordingly. An analog to digital converter (ADC) can be placed after the DAC to generate a digital output. By multiplexing preset digital data into the DAC core for return to zero (RTZ), a true zero that is the midpoint of the DAC output range is achieved. It does not return to a rail for single-ended outputs. RTZ in DAC circuits doubles the null frequency of sin(x)/x roll-off inherent in DACs and also helps reduce switching glitches in the DAC output.

Abstract: Techniques are disclosed for computing distance-to-fault (DTF) in communication systems. The techniques can be embodied, for instance, in a DTF system that provides a multi-port probing device and DTF functionality, including computing distances to faults and the fault magnitudes. In addition, the DTF system is further configured with the ability to accurately measure complex reflection coefficient of the UUT, and/or return loss of the UUT. The complex reflection coefficient and/or return loss of the UUT can be computed as a function of known scattering parameters of a multi-port measurement circuit included in the probe of the DTF system.