US Patent 10381722 Tuned grounding arm for near field radio coexistence

Various arrangements for protecting a low-power sensor from electromagnetic interference are presented. A device may have an antenna that is used to transmit a radio signal and have an on-board low-power sensor. A tuned grounding arm may be capacitively coupled with a ground plane of the antenna. The tuned grounding arm can provide a lower energy return path to a feed point of the antenna than through circuitry of the low-power sensor, thus decreasing near-field interference on the low-power sensor.