Systems and methods for object detection are provided. The system includes at least a coil, a main transmit inverter circuit, and one or more circuits. The one or more circuits are configured to generate a small signal, provide the small signal to the coil, receive a response signal, compare the response signal with one or more reference signals, and detect an object according to the comparison. The object is detected without providing a signal from the main transmit/receive inverter circuit to the coil.