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