T Control field Indication about the maximum size of the A- - Maximum A-MPDU Length Exponent MPDU frame that the access point can handle on reception Use of information Link Adaptation of the variant VHT Link Adaptation Capable HT Control field Indication of a possible change in antenna pattern Receive Antenna Pattern Consistency for reception during the association period Indication of a possible change in antenna pattern Transmit Antenna Pattern Consistency for transmission during the association period Table 5.1. Subfields of the VHT Capabilities Info field 802.11ac Interface The field-supported VHT-MCS and NSS Set is used to transmit the combinations of modulation and coding schemes and spatial streams that an access point supports for transmission and reception. 5.1.1.2. VHT Operation information element The mobile obtains the information on the primary radio channel from the HT Operation information element. The VHT Operation information element provides mobiles with the additional features of the 802.11ac interface and contains the following fields: Channel Width: this field indicates the bandwidth of the radio channel (20, 40, 80, 160 or 80 + 80 MHz). Channel Center Frequency Segment 0: this field indicates the radio channel center for 80 or 160 MHz bandwidths. For the bandwidth of 80 + 80 MHz, this field indicates the center of the 80 MHz radio channel of segment 0. Channel Center Frequency Segment 1: this field indicates the center of the 80 MHz radio channel of segment 1, for the 80 + 80 MHz frequency band. 5.1.1.3. Extended BSS Load information element The Extended BSS Load information element contains information about the underutilization of the MIMO spatial stream and the use of bandwidth. A mobile receiving this piece of information can use it in a specific access point selection algorithm. The Extended BSS Load information element contains the following fields: MU-MIMO Capable STA Count: this field indicates the total number of mobiles associated with the access point whose MU Beamformee Capable 