# WiFi CSI-based device-free sensing: from Fresnel zone model to CSI-ratio model

> Research article (CCF Transactions on Pervasive Computing and Interaction, 2021) · cited 51× · AI/ML

**Wikidata**: [openalex:W3203019240](https://www.wikidata.org/wiki/openalex:W3203019240)  
**Source**: https://4ort.xyz/entity/wifi-csi-based-device-free-sensing-from-fresnel-zone-model-to-csi-ratio-model