ESP32 CSI Collector mac filtering

[mzakharocsc]

Hello,

How does this project ensure that CSI capture is consistent given multiple Access Points in the room? https://github.com/ruvnet/wifi-densepose/blob/main/firmware/esp32-csi-node/main/csi_collector.c#L62 does not capture the mac address of the transmitter, nor performs any kind of filtering.

[ruvnet]

Thanks for the great catch @mzakharocsc! You were absolutely right — the CSI callback wasn't filtering by transmitter MAC, which would cause signal mixing in multi-AP environments.

This has been fixed in PR #101 (merged). Here's what was added:

MAC address logging — every CSI callback now logs the transmitter MAC from info->mac:

ESP_LOGI(TAG, "CSI cb #%lu: len=%d rssi=%d ch=%d mac=%02X:%02X:%02X:%02X:%02X:%02X",
         s_count, info->len, info->rx_ctrl.rssi, info->rx_ctrl.channel,
         info->mac[0], info->mac[1], info->mac[2],
         info->mac[3], info->mac[4], info->mac[5]);

MAC address filtering — new csi_collector_set_filter_mac() API that drops frames from non-matching transmitters:

if (s_filter_enabled) {
    if (memcmp(info->mac, s_filter_mac, 6) != 0) {
        s_filtered++;
        return;
    }
}

Configuration — the filter MAC can be set two ways:

1. Compile-time via Kconfig: CONFIG_CSI_FILTER_MAC="AA:BB:CC:DD:EE:FF"
2. Runtime via NVS: write a 6-byte blob to key filter_mac in namespace csi_cfg (no reflash needed)

Tested on hardware — ESP32-S3 connected to WiFi, CSI flowing with MAC addresses visible in logs. Filter works correctly when enabled.