Premium
Optimal aperture synthesis radar imaging
Author(s) -
Hysell D. L.,
Chau J. L.
Publication year - 2006
Publication title -
radio science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.371
H-Index - 84
eISSN - 1944-799X
pISSN - 0048-6604
DOI - 10.1029/2005rs003383
Subject(s) - inversion (geology) , remote sensing , covariance , synthetic aperture radar , radar , computer science , covariance matrix , algorithm , ionosphere , electrojet , incoherent scatter , geology , geodesy , mathematics , physics , geophysics , telecommunications , statistics , earth's magnetic field , paleontology , structural basin , quantum mechanics , magnetic field
Aperture synthesis radar imaging has been used to investigate coherent backscatter from ionospheric plasma irregularities at Jicamarca and elsewhere for several years. Phenomena of interest include equatorial spread F , 150‐km echoes, the equatorial electrojet, range‐spread meteor trails, and mesospheric echoes. The sought‐after images are related to spaced‐receiver data mathematically through an integral transform, but direct inversion is generally impractical or suboptimal. We instead turn to statistical inverse theory, endeavoring to utilize fully all available information in the data inversion. The imaging algorithm used at Jicamarca is based on an implementation of the MaxEnt method developed for radio astronomy. Its strategy is to limit the space of candidate images to those that are positive definite, consistent with data to the degree required by experimental confidence limits; smooth (in some sense); and most representative of the class of possible solutions. The algorithm was improved recently by (1) incorporating the antenna radiation pattern in the prior probability and (2) estimating and including the full error covariance matrix in the constraints. The revised algorithm is evaluated using new 28‐baseline electrojet data from Jicamarca.