How can I force the bitrate always to 1 Mbps?

[doragasu]

For my application, I need the bitrate to be fixed to 1Mbps. I have been searching the documentation and code, and cannot find the option. So I tried a hack: I set WiFi mode to 802.11b and edited esp_wifi_try_rate_from_high() function in esp_wifi.c for it to always return true to see if this helps. Unfortunately it did not work, when I capture WiFi packets, I can see the bitrate changing to higher values.

So is there a way to force the bitrate to 1Mbps?