The customer could reduce the maximum Tx power used by the WF(M)200 using setting in the Platform Data Set (PDS) file.
Thank to this file, the customer could set some specific parameters for his application. This PDS file is loaded with the firmware in the WF(M)200.
The customer could set the maximun Tx power using the field MAX_OUTPUT_POWER_QDBM:
|/* Power configuration */|
|// Tx power-related information|
|// The max Tx power value in Quarter of dBm (QDBM).|
|// Resultant covered range in dBm: [-32; 31.75]|
The MAX_OUTPUT_POWER_QDBM to 80 means a maximum threshold Tx power of 20dBm.
This is a TX power limitation for all channels and all PHY rate. It is not an adaptive setting and it doesn't allow to force higher TX power level than allowed for the regulatory RF certification or in the datasheet.
For regulatory RF certification, it is recommended for Tx power level reduction to use BACKOFF_QDB in the RF_POWER_CFG Section in the PDS file (see section 3.7 of UG404 and KBA https://www.silabs.com/community/wireless/wi-fi/knowledge-base.entry.html/2021/01/11/wf_m_200_rf_certificationtests-wgIT).
In order to get this maximum Tx power limitation in the PDS file taken into account by the WF(M)200, it should be compressed and installed properly and reloaded.
More details on PDS are available in UG404 : https://www.silabs.com/documents/public/user-guides/ug404-wf200-pds-configuration-users-guide.pdf