DETECTION OF NFC PROXIMITY IC CARDS (PICCS) DURING WIRELESS CHARGING

摘要

Embodiments detect the presence of proximity integrated circuit cards (PICCs) during wireless charging by analyzing the signal strength of a subcarrier within a near field communication (NFC) field. An NFC reader sends requests or other commands to stimulate a response from a PICC that may be in the operating area, and the presence of a PICC is determined based upon the signal strength for the subcarrier. For one embodiment, the subcarrier signal strength is compared to background values measured without stimulus to determine if a PICC is present in the operating area. As such, the presence of a PICC is detectable even where NFC communication with a PICC is unsuccessful because the PICC response is corrupted or not detectable due to interference. Once the presence of a PICC is determined, one or more actions can be taken to protect the PICC from damage due to wireless charging.