Paul Oh Kwon

6437737, Aug 20, 2002

Jan 26, 2000

09/491367

Teodoro Azzarelli - Los Angeles CA
Paul Kwon - Chatsworth CA

Science and Applied Technology, Inc. - San Diego CA

H01Q 300

342360

Data compression method, system, and program code for compressing antenna pattern data generated by measuring the complex voltage derived from the interaction of a RF waveform and a sensing element are disclosed. The antenna pattern data are modeled with a plurality of infinitesimal antenna elements, each element defined in terms of a distinct position, orientation, and polarization. An analytical expression for the interaction between the plurality of infinitesimal antenna elements and an impinging waveform yields a plurality of expressions for a theoretical voltage. The plurality of infinitesimal antenna elements constitute a mathematical basis set from which a weighted linear combination is constructed. The value of the weights are determined by equating the complex voltage representing the antenna pattern data with the theoretical voltage representing the plurality of weighted infinitesimal antenna elements. In turn, the weights comprise an encoded representation of the antenna pattern data from which the antenna pattern data may be reconstructed or decompressed.

61950432, Feb 27, 2001

May 13, 1999

9/311139

Teodoro Azzarelli - Los Angeles CA
Paul Kwon - Chatsworth CA
Ephraim Mendelovicz - Northridge CA

Science and Applied Technology, Inc. - San Diego CA

H01Q 2106

342362

An apparatus and method for determining the angles-of-arrival and the polarization states of incoming RF signals of unknown polarization using five or more RF sensing antenna elements of differing yet known orientations of polarization. The apparatus includes an array of broad gain, substantially identical, RF sensing antenna elements of differing yet known orientations of polarization, an antenna element selection network, RF receiver channels, processing means for determining uncorrected phase differences from received RF signal phases for pairs of antennas, processing means for determining received signal powers, processing means for determining from RF signal powers corrections to the phase difference errors caused by polarization diversity between pairs of antennas, processing means for correcting uncorrected phase differences with determined phase difference corrections, processing means for determining incoming RF signal frequencies, processing means for determining ambiguous and unambiguous angles-of-arrival of incoming RF signals and processing means for determining the polarization states of incoming RF signals.

61409634, Oct 31, 2000

Apr 7, 1999

9/287256

Teodoro Azzarelli - Los Angeles CA
Paul Kwon - Chatsworth CA
Ephraim Mendelovicz - Northridge CA

Science and Applied Technology, Inc. - San Diego CA

G01S 504
H01Q 2106

342442

A method for resolving the angular ambiguity inherent in the differential phase measurements of a source of electromagnetic signal by an interferometric system of antenna elements. Three or more independent differential phase measurements are acquired between predetermined pairs of antenna elements. The ambiguous solutions to each of the differential phase measurements are represented as a group of equally-spaced, parallel lines. The points of intersection between two groups of lines represent ambiguous solutions to the system of equations from which the true angles-of-arrival may be determined. The set of ambiguous solutions is evaluated using the remaining differential phase measurements. The most probable solution to the system of equations is determined by minimizing cost functions with the following embodiments: tightest cluster of intersecting lines; maximum likelihood estimation; and voltage reconstruction comparisons with measured voltages.