US Patent 10996736 Wireless capacitive presence detection

Systems and methods for wireless capacitive presence detection are disclosed. In embodiments, a method includes: generating, by a tank circuit of a wireless presence detector, an electric field applied to a balanced electrode of the wireless presence detector utilizing power from a battery of the wireless presence detector; measuring, by a capacitive sensor of the wireless presence detector, a change in capacitance of the balance electrode; determining, by a microcontroller of the wireless presence detector, that the change in capacitance indicates a presence of a person within a predetermined distance of the balance electrode; and sending, by a radio circuit of the wireless presence detector, an alert to a remote gateway using a radio frequency sub-gigahertz (Ghz) transmission, wherein the alert is based on the determining that the change in capacitance indicates the presence of a person within the predetermined distance of the balance electrode.