{HEAD ~ Feedback} from one or more receivers may be used by {TAIL ~ a transmitter} to improve quality, capacity, and scheduling in MIMO OFDM communication systems 
used by
{ HEAD ~ Feedback } from one or more receivers may be used by { TAIL ~ a transmitter } to improve quality , capacity , and scheduling in MIMO OFDM communication systems
HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH