# US 11,112,521 B2 · Capacitive proximity sensing > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,112,521 B2 - Document ID: US11112521B2 - Status: Granted - Kind: B2 - Application number: 16/444,026 - Filed: 2019-06-18 - Published: 2020-05-07 - Granted: 2021-09-07 - Earliest claimed: 2016-08-30 - Assignees: Intel Corporation - Applicants: Intel Corporation - Inventors: Marcie M. Miller; Roderick E. Kronschnabel; Matthew J. Schneider; Rene J. Sanchez; Christopher L. Ross; Ryan R. Carnaghi; Keith A. Swesey; Kevin Edwards; Steven W. Whitehorn; Cecilia Yancy; Thomas V. Moss - Web page: https://patentgrep.com/patent/US11112521B2 ## CPC - G01V 3/08: operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices (with electromagnetic waves G01V3/12) - G01V: GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS (means for indicating the location of accidentally buried, e.g. snow-buried, persons A63B29/02) ## Abstract A capacitive proximity sensor may include a proximity sensing capacitor to provide a voltage output based on a voltage input, the capacitor including a ground plane and an electrode loop capacitively coupled to the ground plane. The proximity sensor may include a processor to detect an object proximity based on a change in the voltage output. This proximity sensor provides automated detection of a person, and thereby reduces the need for a vehicle occupant or child caregiver to activate a sensor by pressing a button. The use of a capacitance-based proximity sensor reduces issues associated with fabric, clothing, or other materials separating the proximity sensor from a person. ## Claims ### Claim 1 A proximity sensing apparatus comprising: controller circuitry to: receive an output signal from a proximity sensing capacitor, the output signal generated by the proximity sensing capacitor based on a reference signal, the capacitor including a ground plane and an electrode substantially coplanar with and capacitively coupled to the ground plane, the electrode and ground plane to form an electric field in response to the input signal; and detect an object within the electric field based on a change in the output signal; wherein: the output signal has a first frequency associated with the object interacting with the electric field; the output signal has a second frequency associated with the object not interacting with the electric field; and the detection of the object is based on detecting a difference between the first frequency and the second frequency. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the ground plane includes a crosshatch pattern. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the electrode includes a rectangular electrode. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the electrode includes a square electrode. ### Claim 5 (depends on 1) The apparatus of claim 1, further including an overmold supporting the proximity sensing capacitor and controller circuitry. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein the first frequency is lower than the second frequency. ### Claim 7 (depends on 1) The apparatus of claim 1, wherein the input includes a reference clock waveform. ### Claim 8 (depends on 1) The apparatus of claim 1, wherein the input signal includes a periodic time-varying voltage signal. ### Claim 9 (depends on 1) The apparatus of claim 1, wherein: the proximity sensing capacitor has an associated time constant; and the output frequency is based on the time constant. ### Claim 10 (depends on 1) The apparatus of claim 1, wherein the output signal includes a repeating and non-sinusoidal signal. ### Claim 11 A proximity sensing apparatus comprising: means for processing an output signal received from a proximity sensing capacitor, the output signal generated by the proximity sensing capacitor based on a reference signal, the output signal indicative of an object proximate to the proximity sensing capacitor, the capacitor including: a ground plane; and an electrode substantially coplanar with and capacitively coupled to the ground plane, the electrode and ground plane to form an electric field in response to the input signal; and means for detecting an object within the electric field based on a change in the output signal; wherein: the output signal has a first frequency associated with the object interacting with the electric field; the output signal has a second frequency associated with the object not interacting with the electric field; and the detection of the object is based on detecting a difference between the first frequency and the second frequency. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein the ground plane includes a crosshatch ground pattern. ### Claim 13 (depends on 11) The apparatus of claim 11, wherein the electrode includes a rectangular electrode. ### Claim 14 (depends on 11) The apparatus of claim 11, wherein the electrode includes a square electrode. ### Claim 15 (depends on 11) The apparatus of claim 11, wherein the proximity sensing capacitor and controller circuitry are supported by an overmold. ### Claim 16 (depends on 11) The apparatus of claim 11, wherein the first frequency is lower than the second frequency. ### Claim 17 (depends on 11) The apparatus of claim 11, wherein the input includes a reference clock waveform. ### Claim 18 (depends on 11) The apparatus of claim 11, wherein the input signal includes a periodic time-varying voltage signal. ### Claim 19 (depends on 11) The apparatus of claim 11, wherein: the proximity sensing capacitor has an associated time constant; and the output frequency is based on the time constant. ### Claim 20 (depends on 11) The apparatus of claim 11, wherein the output signal includes a repeating and non-sinusoidal signal. ### Claim 21 A proximity sensing apparatus comprising: a proximity sensing capacitor to generate an output signal indicative of an object proximate to the sensing apparatus based on a reference signal, the capacitor including: a ground plane; and an electrode substantially coplanar with and capacitively coupled to the ground plane, the electrode and ground plane to form an electric field in response to the input signal; and controller circuitry electrically coupled to the proximity sensing capacitor, the controller circuitry to detect an object within the electric field based on a change in the output signal; wherein: the output signal has a first frequency associated with the object interacting with the electric field; the output signal has a second frequency associated with the object not interacting with the electric field; and the detection of the object is based on detecting a difference between the first frequency and the second frequency. ### Claim 22 (depends on 21) The apparatus of claim 21, wherein the ground plane includes a crosshatch pattern. ### Claim 23 (depends on 21) The apparatus of claim 21, wherein the electrode includes a rectangular electrode. ### Claim 24 (depends on 21) The apparatus of claim 21, wherein the electrode includes a square electrode. ### Claim 25 (depends on 21) The apparatus of claim 21, further including an overmold supporting the proximity sensing capacitor and controller circuitry. ### Claim 26 (depends on 21) The apparatus of claim 21, wherein the first frequency is lower than the second frequency. ### Claim 27 (depends on 21) The apparatus of claim 21, wherein the input includes a reference clock waveform. ### Claim 28 (depends on 21) The apparatus of claim 21, wherein the input signal includes a periodic time-varying voltage signal. ### Claim 29 (depends on 21) The apparatus of claim 21, wherein: the proximity sensing capacitor has an associated time constant; and the output frequency is based on the time constant. ### Claim 30 (depends on 21) The apparatus of claim 21, wherein the output signal includes a repeating and non-sinusoidal signal. ### Claim 31 A home automation apparatus comprising: a proximity sensing apparatus including: a proximity sensing capacitor to generate an output signal indicative of an object proximate to the sensing apparatus based on a reference signal, the capacitor including: a ground plane; and an electrode substantially coplanar with and capacitively coupled to the ground plane, the electrode and ground plane to form an electric field in response to the input signal; and controller circuitry electrically coupled to the proximity sensing capacitor, the controller circuitry to detect an object within the electric field based on a change in the output signal; and an automation apparatus to perform an action in response to the controller circuitry detecting the object within the electric field; wherein: the output signal has a first frequency associated with the object interacting with the electric field; the output signal has a second frequency associated with the object not interacting with the electric field; and the detection of the object is based on detecting a difference between the first frequency and the second frequency. ### Claim 32 (depends on 31) The home automation apparatus of claim 31, wherein the automation apparatus includes a home monitoring device. ### Claim 33 (depends on 31) The home automation apparatus of claim 31, wherein the automation apparatus includes a wake-up trigger to initiate a connected device. ### Claim 34 (depends on 31) The home automation apparatus of claim 31, wherein the automation apparatus includes a communication device to inform a user of the detection of the object. ### Claim 35 (depends on 31) The home automation apparatus of claim 31, wherein the ground plane includes a crosshatch pattern. ### Claim 36 (depends on 31) The home automation apparatus of claim 31, wherein the electrode includes a rectangular electrode. ### Claim 37 (depends on 31) The home automation apparatus of claim 31, wherein the electrode includes a square electrode. ### Claim 38 (depends on 31) The home automation apparatus of claim 31, further including an overmold supporting the proximity sensing capacitor and controller circuitry. ### Claim 39 (depends on 31) The home automation apparatus of claim 31, wherein the first frequency is lower than the second frequency. ### Claim 40 (depends on 31) The home automation apparatus of claim 31, wherein the input includes a reference clock waveform. ### Claim 41 (depends on 31) The home automation apparatus of claim 31, wherein the input signal includes a periodic time-varying voltage signal. ### Claim 42 (depends on 31) The home automation apparatus of claim 31, wherein: the proximity sensing capacitor has an associated time constant; and the output frequency is based on the time constant. ### Claim 43 (depends on 31) The home automation apparatus of claim 31, wherein the output signal includes a repeating and non-sinusoidal signal.