In certain embodiments, the reader may receive {HEAD ~ the SAPK} from {TAIL ~ the reader}, for example in a combination backscattered by the tag at operation 2002 
In certain embodiments , the reader may receive { HEAD ~ the SAPK } from { TAIL ~ the reader } , for example in a combination backscattered by the tag at operation 2002
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH