802.11ax/HE/Wi-Fi 6 introduced the concept of content channels in the HE preamble. This is further developed into the 802.11be/EHT/Wi-Fi 7 standard. Content channels are used in the EHT MU frame format and therefore, used in most of the EHT data frames sent between stations. This blog article will explain content channels setup for DL OFDMA frame on an 80 MHz channel, and in the end the setup for 20 and 40 MHz channels.
I did a presentation on the same topic for Candela Technology Summit 2025. This video is on YouTube.
So you have two choices: click on the picture for the video or read the rest of this article
Gjermund Raaen 