CSI (Channel Station Information) of WiFi systems is available in some WiFi chips and can be used for environment (people, object, activity) sensing passively and secretly. How could a CSI fuzzer stop unauthorized sensing?  CSI fuzzer implementation principle.  CSI fuzzer in openwifi system architecture and related commands.  Thanks to the full-duplex capability and CSI extraction feature of openwifi, you can monitor the artificial channel response via [side channel](./csi.md) by Tx-Rx over the air coupling without affecting the normal operation/traffic of openwifi. Before the self-monitoring, the auto-mute during Tx needs to be disabled: ``` ./sdrctl dev sdr0 set reg xpu 1 1 ``` CSI self-monitoring before fuzzing.  CSI self-monitoring after fuzzing command: `csi_fuzzer.sh 1 45 0 13`  `csi_fuzzer_scan.sh` can scan the c1 and c2 in different styles/modes by calling `csi_fuzzer.sh`.