SYSTEMS, METHODS, AND APPARATUS FOR DETECTION OF METAL OBJECTS IN A PREDETERMINED SPACE USING THE MAGNETIC FIELD GENERATED BY AN INDUCTIVE POWER TRANSMITTER

摘要

This disclosure provides systems, methods and apparatus for detecting foreign objects. In one aspect an apparatus for detecting a presence of an object in a magnetic field is provided. The apparatus includes a power circuit configured to generate the magnetic field and transfer power wirelessly at a level sufficient to power or charge a load via the magnetic field. The apparatus further includes a detection circuit configured to transmit signals and detect, based on a reflection of the transmitted signals, a frequency of vibration of the object caused by the magnetic field.