How to confirm whether SEM MASK is correct during RFmx WLAN measurement

When you use RFmx WLAN to measure SEM , you will find that the SEM MASK curve of the measurement result is inconsistent with the curve specified in the protocol sometimes . Why is this?
For example, below picture showing that customer use RFmx Waveform Creator to generate WLAN 802.11be 320MHz signal, they use RFmx WLAN to measure SEM and see the following results

We look at the protocol and see the defined MASK as shown below:

How can we confirm that our MASK curve is correct?

1. Looking at the protocol, we found that the definition of MASK is as follows

It can be seen from the above part of protocol  that MASK curve is related to the power spectral density distribution of the signal. When the power spectral density is greater than 40dBr, the above MASK can be applied;

2. Adjust the power of the transmitted signal (increase the transmit power), check the SEM again, you can see the following comparison results

We can see that MASK is consistent with the MASK curve defined by the protocol when High Power is used.

After increasing the transmit power of RF Waveform Creator , we can see the expected MASK curve. So we can confirm that the SEM MASK curve  is calculated from the power spectral density of the received signal.