wifi_csi_info_t missing shape information (AEGHB-856)

[xahlex]

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Issue or Suggestion Description

wifi_csi_info_t missing shape information

• Checked the issue tracker for similar issues to ensure this is not a duplicate
• Read the documentation to confirm the issue is not addressed there and your configuration is set correctly
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Issue Description

For each RX and TX Antenna pair, a single CSI matrix should be delivered.
Since the ESP only has one Antenna the number of received CSI must depend on the peer's number of antennas.
Thus there should be an attribute in the wifi_csi_info struct explaining the shape of CSI. Is it possible the CSI matrix is flattened unbeknownst to the user?

I couldn't find an official reference for this problem, but here is the link to the cited paper: here

[NingYuxiang]

You can refer to the table under Wi-Fi Channel State Information, where the information under the STBC classification explains the CSI data shape for multiple antennas.

You can infer the CSI shape based on the information in wifi_csi_info_t . To check the valid data length, read it from rx_ctrl->sig_len . The CSI data shape can then be deduced from the valid data length.