Department of Electrical and Computer Engineering;
Binghamton University;
Binghamton;
NY 13902;
U.S.A.;
CAS Key Laboratory of Electromagnetic Space Information;
University of Science and Technology of China;
Hefei 230026;
China;
Department of Electrical and Computer Engineering;
University of Florida;
GainesviUe;
FL 32611;
U.S.A.;
Department of Computer Science and Information Engineering;
'National' Taiwan University;
Taipei 10617;
China;