| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 342432000 | With plural fixed antenna pattern comparing | 7 |
| 20090079635 | METHOD AND APPARATUS FOR ADAPTIVE DIRECTION ESTIMATION OF RADIO WAVES - In an environment of temporally and spatially uncorrelated white additive noise, the direction estimation apparatus for coherent signals calculates (M−1) instantaneous cross-correlations between some array data, and selecting multiple pairs each of which is consisted of p instantaneous correlations from the (M−1) instantaneous cross-correlations to form a Hankel correlation matrix. Next, the apparatus divides that Hankel matrix into an upper submatrix and a lower submatrix and then calculates a linear operator at time n by using the adaptive LMS algorithm with a fixed or time-varying step-size parameter and or using the adaptive NLMS algorithm from the two submatrices. Then a noise subspace is estimated from that linear operator. Finally the directions of incident signals at time n is estimated and tracked by using that noise subspace with Newton approximation. | 03-26-2009 |
| 20110068980 | DIRECTION FINDING METHOD AND DEVICE - The invention relates to a method for determining whether a target is within a direction sector of interest of a direction finder, which comprises: (a) predefining said sector of interest as a specific threshold difference between an R reference value and an N null value; (b) providing at least two antennas arranged in a broad-side configuration within the direction finder; (c) generating an in-phase reference pattern using at least one of said antennas, and establishing wireless communication between the direction finder and said target; (d) attenuating the wireless communication signal between the direction finder and said target until the wireless communication is lost, and recording the attenuation value which corresponds to said loss of wireless communication as the R reference value; (e) generating an out-of-phase null pattern using at least two of said antennas, and re-establishing wireless communication between the direction finder and said target; (f) attenuating the wireless communication signal between the direction finder and said target until the wireless communication is lost, and recording the attenuation value which corresponds to said loss of wireless communication as the N null value; (g) determining whether the difference R−N is above or below said threshold difference, wherein a difference R−N above said threshold is an indication that the target is within said direction sector of interest, and wherein a difference R−N below said threshold is an indication that the target is out of said direction sector of interest. The invention also relates to a device for carrying out said method. | 03-24-2011 |
| 20130002489 | DIRECTION FINDING SYSTEM DEVICE AND METHOD - The present invention relates to a method for determining the direction to a target by a direction finder, which comprises: predefining a direction axis as a 0° direction; first and second pair of antennas arranged such that a first line connecting between the first pair of antennae defines a 0°-180° axis parallel to said direction axis, and a second line connecting said second pair of antennas defines a 90°-270° axis perpendicular to said direction axis; generating a 0° antenna pattern and establishing a wireless communication between the direction finder and said target; attenuating the wireless communication signal until lost and recording the attenuation value; generating a 180° antenna pattern using said first pair of antennas, and establishing a wireless communication between the direction finder and said target; attenuating the wireless communication signal until lost, and recording the attenuation value and concluding a true direction to the target. | 01-03-2013 |
| 20130099975 | SEARCH AND RESCUE METHOD AND SYSTEM - A method for locating a transmitter using a receiver which include, but are not limited to the steps of transmitting a plurality of distinctive and orthogonally polarized signals from a transmitter; receiving the transmitted signals at a pair of separated antennas; demodulating the distinctive orthogonal signals received at each of the pair of separated antennas; and determining a direction to the transmitter from the signals received at the pair of antennas. The system for determining the location of a transmitter using a receiver includes, but is not limited to, having a transmitter adapted for orthogonally transmitting a plurality of distinctive signals; a receiver having a pair of separated antennas for receiving the orthogonally transmitted signals; separate demodulators in the receiver for each antenna of the pair of separated antennas for demodulating the distinctive signals; and signal processing circuitry in the receiver adapted for using the demodulated distinctive signals for determining a direction to the transmitter. | 04-25-2013 |
| 20140152503 | DIRECTION OF ARRIVAL ESTIMATION USING LINEAR ARRAY - A linear array of sensors includes at least two omni-directional sensors and at least one directional sensor, with the axis of sensitivity of the directional sensor arranged, e.g., perpendicular to the linear axis of the linear array. The omni-directional sensors and directional sensor receive a signal and in response produce output signals. The direction of arrival of the received signal is estimated with a 360° range using the output signals of the omni-directional sensors and directional sensor. For example, two symmetric solutions for the direction of arrival of the received signal may be determined using the output signals of the omni-directional sensors, and the output signal from the directional sensor is used to determine the correct solution. | 06-05-2014 |
| 342433000 | Successively commutated | 1 |
| 342434000 | Including more than two antennas | 1 |
| 20140104110 | Method for Real-time, Automatic, Wideband, High Accuracy RF Direction Finding - This system and method provides a direction finding system that enables modern RF DF systems to analyze short duration signals in the entire instantaneous bandwidth. By providing a method to process wideband data, the invention drastically improves throughput and probability of intercept (POI). The invention is unique in that it does not require separate narrowband channels for analysis, and can simultaneously calculate azimuth and elevation estimates for every frequency in the bandwidth of an incident signal. It is also well-suited for fixed point, FPGA implementations making it a perfect match for modern state-of-the-art processing systems. The system and method capitalizes on the ability of Fourier Frequency Transform operations to accurately resolve incident wave phase at discrete frequencies. The system then uses the phase information from the individual elements in the array to arrive at an emitter azimuth angle. The azimuth angle is nearly simultaneously used in concert with lookup tables of all possible elevation angles to compare the arrival time delay between the array elements to determine emitter elevation angle. | 04-17-2014 |
| 342437000 | Including more than two antennas | 1 |
| 20140152504 | METHOD AND SYSTEM FOR MEASURING DIRECTION OF ARRIVAL OF WIRELESS SIGNAL USING CIRCULAR ARRAY DISPLACEMENT - The various embodiments herein provide a Uniform Circular Displaced Sensor Array (UC-DSA) system and method for measuring/estimating Direction of Arrival (DOA) of a wireless signal. The UC-DSA system comprises at least a set of two circular antenna arrays. The two circular antenna arrays have a number of elements. A Radio frequency (RF) receiver captures a wireless signal incident on a circular antenna array. A Direction of Arrival (DOA) estimator processes a received input signal and a Triangulation system provides the exact location of the source of the wireless signal. The two circular antenna arrays with the same number of elements are placed on different radii, and are shifted to have equal separation between inner elements and outer elements. | 06-05-2014 |
