Comparison of synthetic aperture radar autofocus techniques---Phase gradient vs subaperture

Conference · Tue Jan 01 00:00:00 EST 1991

OSTI ID:5618434

Calloway, T M; Jakowatz, Jr, C V; Thompson, P A; Eichel, P H

Two methods of focusing synthetic aperture radar (SAR) images are compared. Both a conventional subaperture cross-correlation method and a new phase gradient autofocus (PGA) algorithm developed at Sandia National Laboratories are shown to perform well if high-order phase errors are not present. With the introduction of significant high-order phase errors (e.g., due to uncompensated platform motion), both algorithms suffer a loss in performance. However, relative performance degradation is less for PGA than for the subaperture focusing technique. An explanation is presented for the observed behavior of the two autofocus techniques. 8 refs., 8 figs.

• Research Organization: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
• Sponsoring Organization: USDOE; USDOE, Washington, DC (USA)
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 5618434
• Report Number(s): SAND-91-0057C; CONF-9107115-5; ON: DE91014696
• Resource Relation: Conference: Society of Photo-Optical Instrumentation Engineers (SPIE) meeting, San Diego, CA (USA), 21-26 Jul 1991
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
47 OTHER INSTRUMENTATION
99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE
SYNTHETIC-APERTURE RADAR
FOCUSING
ALGORITHMS
APERTURES
COMPARATIVE EVALUATIONS
COMPUTERIZED SIMULATION
CORRELATIONS
IMAGES
LEGENDRE POLYNOMIALS
PHASE SHIFT
FUNCTIONS
MATHEMATICAL LOGIC
MEASURING INSTRUMENTS
OPENINGS
POLYNOMIALS
RADAR
RANGE FINDERS
SIMULATION
420200* - Engineering- Facilities
Equipment
& Techniques
440800 - Miscellaneous Instrumentation- (1990-)
990200 - Mathematics & Computers