Keysight M9383B Measurement Manual page 129

5G NR Measurements Using the VSA Software
5G Waveform and EVM Analysis Using VSA Software
11.From the Channel pane, select PDSCH and then set the following
3GPP has different Tables for PDSCH MCS.
TIP
M9383B/84B Measurement Guide
For example, to calculate the 120 kHz sub-carrier spacing, the value
would be
66RB/2 = 33 RB
This is the center of the carrier bandwidth. However, the SS Block is 
20 RB wide, so the start of the SS Block is 23 RB.
23 RB in 120 kHz is 23 * 2 = 46 RB in 60 kHz
This is the default value used in the VSA software for 120 kHz numerology.
parameters:
— Under Modulation and Config section, set MCS Table to Table
256QAM and MCS to 20.
Table 5.1.3.1-2 has 256 QAM as maximum modulation
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