5 ms·
Also > It should be noted that many WiFi routers, such as TP-Link AC1750, come with 3 antennas, so our method only requires 2 of these routers. > WiFi-based
by est 3y ago
Also
> It should be noted that many WiFi routers, such as TP-Link AC1750, come with 3 antennas, so our method only requires 2 of these routers.
> WiFi-based perception is based on the Channel-state-information (CSI) that represents the ratio between the transmitted signal wave and the received signal wave. The CSIs are complex decimal sequences that do not have spatial correspondence to spatial locations
AFAIK, access to raw CSI data is not available on consumer routers. You need specific FPGA/SDR boards which happens to speak the WIFI 2.4G/5G protocol.
There are some open sources efforts such as https://github.com/open-sdr/openwifi https://github.com/open-sdr/openwifi
- transpute 3y ago> FPGA/SDR boards Custom firmware is available for existing WiFi radios, e.g. sub-$20 ESP32 WROOM. Previous HN discussion: https://news.ycombinator.com/item?id=34480760 https://news.ycombinator.com/item?id=34480760
- est 3y agoThus "Your wifi" can not see you unless you setup ESP32 as router and allows remote ROM updates.
- transpute 3y agoA nearby adversary can "see" into your home/building without any access to your router's software or hardware. A nearby adversary needs only the reflections of Wi-Fi from your or neighboring routers.
- jxj 3y agoWe do even further. If we use openwifi as a router in home, it can fuzz the CSI and destroy those sensing method: https://github.com/open-sdr/openwifi/blob/master/doc/app_notes/csi_fuzzer.md https://github.com/open-sdr/openwifi/blob/master/doc/app_not...