VIAVI TestCenter: How can we specify 256-QAM in the STC GUI?
Knowledge Base - FAQ
VIAVI TestCenter: How can we specify 256-QAM in the STC GUI?
VHT is different than HT in IEEE802.11 spec.
HT has one bit for every MCS index, thus we can specify from MCS0 ~ MCS7 for each spatial stream:
VHT only has two bits which only can specify either of following 4 cases:
However, in STC if Use highest MCS index is checked, then STC force to transmit at the highest MCS index selected, e.g. If 0-8 and Use highest MCS index are checked STC force to transmit at MCS8 which is 256QAM 3/4 but, if 0-9 and Use highest MCS index are checked STC force to transmit at MCS9 which is 256QAM 5/6.