Difference in CSI Data Length (AEGHB-1257) #238

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Issue or Suggestion Description

I am using an ESP32C5 to obtain CSI information with the following settings:

STA Mode Configuration
Frequency Band: 5GHz
Bandwidth: 20MHz
Protocol: 11ac
PHY Mode: HT20
wifi_csi_config_t csi_config = {
.enable = true,
.acquire_csi_legacy = false, // Set to true if legacy management frames are needed
.acquire_csi_force_lltf = CSI_FORCE_LLTF,
.acquire_csi_ht20 = false,
.acquire_csi_ht40 = false,
.acquire_csi_vht = true,
.acquire_csi_su = false,
.acquire_csi_mu = false,
.acquire_csi_dcm = false,
.acquire_csi_beamformed = false,
.acquire_csi_he_stbc_mode = 0,
.val_scale_cfg = 0,
.dump_ack_en = false,
.reserved = false
};

Access Point (AP) Configuration
Router: A wireless router set to AP mode
Frequency Band: 5GHz
Bandwidth: 20MHz
Protocol: 11ac/n/a
When obtaining CSI data with these settings, the CSI data length is 228.
On the other hand, when using ESP-NOW with the same conditions (11ac, 5GHz, 20MHz), the CSI data length is 114.

Assumption
For a 20MHz bandwidth, I expect the CSI data length to be 114, calculated as follows:

Data carriers: 52
Pilot carriers: 4
Center carrier: 1
Each has both amplitude and phase, so the total is: (52 + 4 + 1) × 2 = 114
Questions
Why is the CSI data length 228 when obtained in STA mode?
What is the reason for the difference compared to the 114 data length when using ESP-NOW?
Additional Information
If any additional information is required to resolve this issue, please let me know.
I have also attached a serial output image of the CSI data obtained with the wireless router in AP mode.