Patent ID: 7250863

Claim:
A reader/writer comprising: a first coil antenna for carrying communication between a plurality of transponders each transponder including: a sensor block having a sensor performing a prescribed measurement, and a unique identifier combining a transponder chip identifier and a sensor identifier; a communication circuit to which said first coil antenna is connected; an oscillator; a modulator for modulating an oscillation frequency generated by said oscillator and supplying the resultant modulated signals to said communication circuit; a demodulator for demodulating signals resulting from the reception by said communication circuit of signals sent from said transponder via said first coil antenna; and a control block for controlling said oscillator, said modulator, said communication circuit and said demodulator, provided with: a command for invalidating a transponder chip identifier out of said unique identifiers in order to enable transponders each with a built-in prescribed sensor out of said plurality of transponders to start measurement.