To provide a transceiver applicable to a system for handling baggage.

The transceiver includes an electric circuit having a series resistance to which modulation processing is performed in a form of resistor R(modulator). Moreover, a parallel switch SW1 is included in an AC part of a circuit between an antenna and a preservation capacitor. In another embodiment, an R (modulator) being a series resistance to which the modulation processing is performed, and the parallel switch SW1 are installed in a DC part of a circuit between the antenna and the preservation capacitor. Both the circuits provide an identical transmitted signal. Because of the DC operation bias, the latter is actually easier to use. In the embodiment, the series resistance to which the modulation processing is performed is installed between the antenna and a tuning capacitor of the antenna.