To provide a transmission/reception system and a transmission/reception method, which manages a content amount of content stored in a storage container by detecting an existence position of a wireless type transmission device.
A carrier wave having a frequency of 13.56 MHz is transferred between an external transmission/reception device 10 and the wireless type transmission device 20, in a load modulation system. The external transmission/reception device 10 transmits a transmission signal (modulated carrier wave). The wireless type transmission device 20 outputs successively a plurality of reply signals (modulated sub-carrier wave components) having each different amplitude level in response to the transmission signal from the external transmission/reception device 10. Each of the plurality of reply signals includes ID information and level information showing the amplitude level of the reply signal. When receiving the reply signal from the wireless type transmission device 20, the external transmission/reception device 10 determines a communication distance between the external transmission/reception device 10 and the wireless type transmission device 20, based on detected level information, when a signal state of the received reply signal satisfies a prescribed condition and the ID information and the level information is detected from inside the reply signal.