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9.26.1.2 PSMP downlink transmission (PSMP-DTT)............................................. 157
9.27 Sounding PPDUs ....................................................................................................................... 158
9.28 Link adaptation .......................................................................................................................... 158
9.28.2 Link adaptation using the HT variant
HT Control field .............................................. 158
9.28.3 Link adaptation using the VHT variant HT Control field ........................................... 159
9.29 Transmit beamforming .............................................................................................................. 162
9.29.1 General
HT steering matrix calculations ..................................................................... 162
9.29.2 HT t
Transmit beamforming with implicit feedback.................................................... 162
9.29.2.1 General....................................................................................................... 162
9.29.2.3 Bidirectional implicit transmit beamforming ............................................ 164
9.29.2.4 Calibration ................................................................................................. 164
9.29.3 Explicit feedback beamforming................................................................................... 164
9.29.4 VHT MU beamforming ............................................................................................... 165
9.30 Antenna selection (ASEL)......................................................................................................... 165
9.30.1 Introduction ................................................................................................................. 165
9.31 Null data packet (NDP) sounding.............................................................................................. 165
9.31.1 NDP rules .................................................................................................................... 165
9.31.2 Transmission of an HT
NDP ....................................................................................... 167
9.31.3 Determination of HT
NDP destination........................................................................ 167
9.31.4 Determination of HT
NDP source ............................................................................... 167
9.31.5 VHT sounding protocol............................................................................................... 168
9.31.5.1 General....................................................................................................... 168
9.31.5.2 Rules for VHT sounding protocol sequences ............................................ 168
9.31.5.3 Rules for fragmented feedback in VHT sounding protocol sequences ..... 172
9.31.6 Transmission of a VHT NDP ...................................................................................... 173
10. MLME .................................................................................................................................................. 174
10.1 Synchronization ......................................................................................................................... 174
10.1.3 Maintaining synchronization ....................................................................................... 174
10.1.3.2 Beacon generation in non-DMG infrastructure networks ......................... 174
10.2 Power management.................................................................................................................... 174
10.2.1 Power management in a non-DMG infrastructure network ........................................ 174
10.2.1.17 TIM broadcast............................................................................................ 174
10.2.1.19 VHT TXOP power save ............................................................................ 175
10.3 STA authentication and association........................................................................................... 176
10.3.5 Association, reassociation, and disassociation ............................................................ 176
10.3.5.3 PCP/AP association receipt procedures..................................................... 176
10.3.5.5 PCP/AP reassociation receipt procedures.................................................. 176
10.8 TPC procedures.......................................................................................................................... 176
10.8.2 Association based on transmit power capability ......................................................... 176
10.8.3a Interpretation of transmit power capability ................................................................. 177
10.8.4 Specification of regulatory and local maximum transmit power levels ...................... 177
10.9 DFS procedures.......................................................................................................................... 178
10.9.3 Quieting channels for testing....................................................................................... 178
10.11 Radio measurement procedures................................................................................................. 179
10.11.9 Specific measurement usage........................................................................................ 179
10.11.9.1 Beacon Report ........................................................................................... 179
10.11.9.3 Channel Load Report................................................................................. 180
10.11.9.4 Noise Histogram Report ............................................................................ 181
10.11.18AP Channel Report...................................................................................................... 181
10.15 20/40 MHz BSS operation......................................................................................................... 181
10.15.2 Basic 20/40 MHz BSS functionality ........................................................................... 181
10.15.8 Support for DSSS/CCK in 40 MHz............................................................................. 182