Abstract: A multi-function card has a non-contact IC card function, a magnetic stripe card function, a function of generating a magnetic card signal and an NFC signal, and a Bluetooth function capable of transmitting a signal to devices such as smartphones. The multi-function card includes a metallic frame, and is robust against bending or breakage. A transmission/reception sensor system is used for the multi-function card or the like, and for a wearable device. The transmission/reception sensor system includes a magnetic sensor 10 including a coil 2 wound around a magnetic sensor core 1, and an NFC coil 12 formed in a planar shape. A metallic frame having of a loop shape is installed along the NFC coil 12 and includes one or more cut portions.