Batteryless backscatter sensor networks—Part II: lessons from scalable deploymentBatteryless backscatter sensor networks—Part II: lessons from scalable deployment Peer-Reviewed Journal Publication Δημοσίευση σε Περιοδικό με Κριτές 2025-04-302023enInspired by the challenges presented in Part I, Part II examines analog ambient backscatter for scalable, batteryless, wireless and ultra-low cost sensing of soil moisture. Ultra-low power ambient backscatter sensors are built, with accuracy below 4%, cost of a few euros per sensor and ability to report soil moisture to any conventional FM radio-equipped smartphone. Calibration, characterization, extensive usage and evaluation was conducted in research greenhouses and small-scale farms. Probabilistic graphical model-based algorithms were also devised that complete missing measurements. Hopefully, this work will spark further interest in batteryless backscatter sensor networks with holistic approaches and tremendous socioeconomic impact.The research work was supported by the Hellenic Foundation for Research and Innovation (H.F.R.I.) under the “First Call for H.F.R.I. Research Projects to support Faculty members and Researchers and the Procurement of High-cost research equipment” (Project Number: 2846).http://creativecommons.org/licenses/by/4.0/IEEE Communications Letters273768-772 Vougioukas Georgios Βουγιουκας Γεωργιος Ntantidakis Nikolaos Νταντιδακης Νικολαος Karatarakis Evangelos Καραταρακης Ευαγγελος Apostolakis Georgios Αποστολακης Γεωργιος Bletsas Aggelos Μπλετσας Αγγελος Institute of Electrical and Electronics Engineers Backscatter Sensor networks Inference Environmental monitoring