7,674 research outputs found
Imaging ionospheric inhomogeneities using spaceborne synthetic aperture radar
We present a technique and results of 2-D imaging of Faraday rotation and total electron content using spaceborne L band polarimetric synthetic aperture radar (PolSAR). The results are obtained by processing PolSAR data collected using the Phased Array type L-band Synthetic Aperture Radar (PALSAR) on board the Advanced Land Observation Satellite. Distinguished ionospheric inhomogeneities are captured in 2-D images from space with relatively high resolutions of hundreds of meters to a couple of kilometers in auroral-, middle-, and low-latitude regions. The observed phenomena include aurora-associated ionospheric enhancement arcs, the middle-latitude trough, traveling ionospheric disturbances, and plasma bubbles, as well as ionospheric irregularities. These demonstrate a new capability of spaceborne synthetic aperture radar that will not only provide measurements to correction of ionospheric effects in Earth science imagery but also significantly benefit ionospheric studies
On MDS Codes With Galois Hulls of Arbitrary Dimensions
The Galois hulls of linear codes are a generalization of the Euclidean and
Hermitian hulls of linear codes. In this paper, we study the Galois hulls of
(extended) GRS codes and present several new constructions of MDS codes with
Galois hulls of arbitrary dimensions via (extended) GRS codes. Two general
methods of constructing MDS codes with Galois hulls of arbitrary dimensions by
Hermitian or general Galois self-orthogonal (extended) GRS codes are given.
Using these methods, some MDS codes with larger dimensions and Galois hulls of
arbitrary dimensions can be obtained and relatively strict conditions can also
lead to many new classes of MDS codes with Galois hulls of arbitrary
dimensions.Comment: 21 pages,5 table
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