Richard R Goldstein

US Patent:

41124979, Sep 5, 1978

Filed:

Mar 29, 1977

Appl. No.:

5/782464

Inventors:

James C. Administrator of the National Aeronautics and Space Fletcher
James W. Layland - La Canada CA
Warren L. Martin - La Canada CA
Arthur I. Zygielbaum - Arcadia CA
Richard M. Goldstein - La Canada CA
William P. Hubbard - Glendale CA

International Classification:

G06F 1534
G01S 938

US Classification:

364728

Abstract:

Apparatus for demodulation and correlation of a code modulated 10 MHz signal is comprised of a sample and hold analog-to-digital (A/D) converter synchronized by a frequency coherent 40 MHz pulse to obtain four evenly spaced samples A1,B1,A2 and B2 of each cycle of the signal, and means for adding, or subtracting, each sample to, or from, one of four accumulators to form the sums: ##EQU1## where M1 = 10 MHz Reference. multidot. Receiver Code. angle. degree. M2 = 10 mhz Reference. multidot. Receiver Code. angle. 90. degree. The correlation functions that are used for the range measurements are then computed from the following equations: I = S1. sub. I cos. alpha. - S2. sub. I sin. alpha. Q = S1. sub. Q cos. alpha. - S2. sub. Q sin. alpha. where sin. alpha. and cos. alpha.

US Patent:

45517240, Nov 5, 1985

Filed:

Feb 10, 1983

Appl. No.:

6/465365

Inventors:

Richard M. Goldstein - La Canada CA
Edward R. Caro - Monterey Park CA
Chialin Wu - Pasadena CA

Assignee:

The United States of America as represented by the Administrator of the
National Aeronautics and Space Administration - Washington DC

International Classification:

G01S 1390

US Classification:

343 5CM

Abstract:

By using two SAR antennas spaced a known distance, B, and oriented at substantially the same look angle to illuminate the same target area, pixel data from the two antennas may be compared in phase to determine a difference. DELTA. phi. from which a slant angle. theta. is determined for each pixel point from an equation. DELTA. phi. =(2. pi. B/. lambda. )sin(. theta. -. alpha. ), where. lambda. is the radar wavelength and. alpha. is the roll angle of the aircraft. The height, h, of each pixel point from the aircraft is determined from the equation h=R cos. theta. , and from the known altitude, a, of the aircraft above sea level, the altitude (elevation), a', of each point is determined from the difference a-h. This elevation data may be displayed with the SAR image by, for example, quantizing the elevation at increments of 100 feet starting at sea level, and color coding pixels of the same quantized elevation. The distance, d, of each pixel from the ground track of the aircraft used for the display may be determined more accurately from the equation d=R sin. theta.

US Patent:

49757040, Dec 4, 1990

Filed:

Jan 26, 1990

Appl. No.:

7/470665

Inventors:

Andrew K. Gabriel - Altadena CA
Richard M. Goldstein - La Canada CA
Howard A. Zebker - Altadena CA

Assignee:

The United States of America as represented by the Administrator of the
National Aeronautics and Space Administration - Washington DC

International Classification:

G01S 1390

US Classification:

342 25

Abstract:

A technique based on synthetic aperture radar (SAR) interferometry is used to measure very small (1 cm or less) surface deformations with good resolution (10 m) over large areas (50 km). It can be used for accurate measurements of many geophysical phenomena, including swelling and buckling in fault zones, residual, vertical and lateral displacements from seismic events and prevolcanic swelling. Two SAR images are made of a scene by two spaced antennas and a difference interferogram of the scene is made. After unwrapping phases of pixels of the difference interferogram, surface motion or deformation changes of the surface are observed. A second interferogram of the same scene is made from a different pair of images, at least one of which is made after some elapsed time. The second interferogram is then compared with the first interferogram to detect changes in line of sight position of pixels. By resolving line of sight observations into their vector components in other sets of interferograms along at least one other direction, lateral motions may be recovered in their entirety.