Title :
Maximum-likelihood ISAR image autofocusing technique based on instantaneous frequency estimation
Author :
Berizzi, F. ; Pinelli, G.
Author_Institution :
Dipt. di Ingegneria dell´´Inf., Pisa Univ., Italy
fDate :
10/1/1997 12:00:00 AM
Abstract :
The authors consider the problem of motion compensation in the inverse synthetic aperture radar (ISAR) imaging technique. A novel autofocusing technique based on maximum-likelihood (ML) estimation of the focusing parameters is proposed. The likelihood function is computed by using as observed data samples of the instantaneous frequency (IF) of the received signal. A statistical analysis of the IF is performed, both to determine the likelihood function and to define a criterion for the choice of IF samples to be processed. The effectiveness of the autofocusing algorithm is shown by presenting and discussing some simulation results
Keywords :
focusing; frequency estimation; image sampling; maximum likelihood estimation; motion compensation; radar imaging; statistical analysis; synthetic aperture radar; ISAR image autofocusing; ISAR imaging; MLE; autofocusing algorithm; focusing parameters; instantaneous frequency estimation; inverse synthetic aperture radar; likelihood function; maximum likelihood estimation; motion compensation; observed data samples; received signal; simulation results; statistical analysis;
Journal_Title :
Radar, Sonar and Navigation, IEE Proceedings -
DOI :
10.1049/ip-rsn:19971398