Class / Patent application number | Description | Number of patent applications / Date published |
342445000 | Having more than two antennas | 8 |
20090066578 | SYSTEM AND METHOD FOR CUMULANT-BASED GEOLOCATION OF COOPERATIVE AND NON-COOPERATIVE RF TRANSMITTERS - A transmitted signal's higher order statistics of temporally dependent waveforms are exploited to geolocate low power signals. The geolocation is independent of the characteristics or encoded data of the transmitted waveform. The method uses spatial fourth order cumulants or spatial second order moments in a Blind Source Separation and generalized eigenvalue decomposition to determine unique matrix pencil eigenvalues and eigenvectors. The eigenvectors provide are orthogonal to the steering vector of the transmitted signal save one, which represents the steering vector. This property is used to determine Steering vectors, AoA or geolocation. The receiver includes a multi-element array and does not need a priori knowledge of the transmitted signal source to geolocate the target transmitter. The methods and apparatus for geolocation does not require typical demodulation. | 03-12-2009 |
20100231455 | METHOD AND SYSTEM FOR DETECTING SIGNAL SOURCES IN A SURVEILLANCE SPACE - A respective electromagnetic parameter and spatial disposition of an unknown number of signal sources in a surveillance space simultaneously bombarded by multiple signals are determined by receiving multiple signals at each of a plurality of widebeam, wideband antennas equally spaced apart in a linear array. Respective antenna signals are simultaneously sampled to generate a two-dimensional array of values. A two-dimensional Fourier transform is computed whose peaks satisfy one or more predetermined criteria, each peak being indicative of a signal source in the surveillance space, whereby the location of the peak in the Fourier transform Fjk indicates the frequency and the azimuth of the respective signal source and the amplitude of the peak indicates the amplitude of the signal source. When implemented using two mutually perpendicular arrays of receiving antennas, an additional Fourier transform of the two-dimensional Fourier transform generates, for each identified emitter, independent azimuth and elevation angles. | 09-16-2010 |
20100321242 | DIRECTION FINDING AND GEOLOCATION OF WIRELESS DEVICES - 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. | 12-23-2010 |
20110181473 | TRANSIENT RF DETECTOR AND RECORDER - A portable device for detecting a radio frequency transmission of electromagnetic radiation includes a housing; a controller situated within the housing; memory communicatively connected to the controller; an antenna connected to the controller and configured to receive the radio frequency transmission; and an audio-generating component connected to the controller. The radio frequency transmission of the electromagnetic radiation is harmful to an electrical device and is from a transient electromagnetic device (TED) threat source. The controller is operative for sensing magnitude, duration, and/or repetition of the radio frequency transmission; identifying a class of the radio frequency transmission based on one of the magnitude, duration, and repetition associated with the radio frequency transmission; and causing the audio-generating component to output tones to provide aural discrimination of an identified class of the radio frequency transmission received by the portable device. The identified class is a transient electromagnetic pulse signal from the TED source. | 07-28-2011 |
20110304509 | Method and System for Detecting Signal Sources in a Surveillance Space - A respective electromagnetic parameter and spatial disposition of an unknown number of signal sources in a surveillance space simultaneously bombarded by multiple signals are determined by receiving multiple signals at each of a plurality of widebeam, wideband antennas equally spaced apart in a linear array. Respective antenna signals are simultaneously sampled to generate a two-dimensional array of values. A two-dimensional Fourier transform is computed whose peaks satisfy one or more predetermined criteria, each peak being indicative of a signal source in the surveillance space, whereby the location of the peak in the Fourier transform Fjk indicates the frequency and the azimuth of the respective signal source and the amplitude of the peak indicates the amplitude of the signal source. When implemented using two mutually perpendicular arrays of receiving antennas, an additional Fourier transform of the two-dimensional Fourier transform generates, for each identified emitter, independent azimuth and elevation angles. | 12-15-2011 |
20120032853 | Direction Finding Antenna - An apparatus for a direction finding system is described. The apparatus includes at least three antenna elements. Each antenna element faces in a facing direction different than the other antenna elements. An individual antenna element has a substantially smooth polarization gain in the corresponding facing direction. Each antenna element includes a feeding branch, a parasitic branch and a back plate. The parasitic branch and the feeding branch are disposed in a first plane perpendicular to the feeding direction. The back plate is disposed in a second plane parallel to the first plane and the second plane is behind the first plane. The apparatus may be used to receive at least one signal from a transmitter. A distance and a direction from the apparatus to the transmitter may be determined based at least in part on the received at least one signal. Methods and computer readable media are also described. | 02-09-2012 |
20150070217 | MICROWAVE RADIO DIRECTION FINDING SYSTEM - The microwave radio direction finding system includes two six-port (SP) circuits and 2×2 printed patch antennas, each of the SP circuits having a pair of the patch antennas connected to their inputs, one pair being separated horizontally in a Cartesian plane, the other pair being separated vertically. The output ports are connected to differential amplifiers that produce in-phase and quadrature signals, which are digitized and input to a digital signal processor, which computes the difference in phase for the signals received at each pair of antennas. The processor uses the differences in phase angles to compute both the azimuth and elevation of the received signals, and may do so simultaneously for signals in multiple bands in the microwave region. | 03-12-2015 |
20190146057 | RADIO FREQUENCY COMMUNICATION SYSTEM | 05-16-2019 |