1. Sensors and Electron Devices Directorate, US Army Research Laboratory, Adelphi, MD 20783, USA
2. Department of Mathematics, Wake Forest University, Winston-Salem, NC 27106, USA
3. Space Data Systems Group, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
4. Department of Electrical and Computer Engineering, University of Missouri, Columbia, MO 65211, USA