This work is supported by the Telemedicine and Advanced Technology Research Center (TATRC) at the U.S. Army Medical Research and Materiel Command (USAMRMC) through award W81XWH-11-2-0025, and Defense Advanced Research Projects Agency (DARPA) Award No. FA8750-12-2-0325. Any design guidance, opinions, findings, conclusions or recommendations expressed here are those of the authors and do not necessary reflect the views of TATRC or DARPA.