Noncontact communication medium, magnetic tape cartridge, noncontact communication system, operation method of noncontact communication medium, and program

An operation method of a noncontact communication medium that performs communication with an external device in a noncontact manner via a magnetic field provided from the external device, the noncontact communication medium including a resonance circuit that generates an alternating current voltage by resonating using an induced current induced in an antenna coil by the magnetic field acting on the antenna coil, a regulator that generates operating power for operating a processing circuit, from power based on a direct current voltage obtained by rectifying the alternating current voltage, a variable resistor connected to the resonance circuit, a switcher, and a control circuit, the operation method comprising:

• generating, via the processing circuit, a response signal corresponding to a command signal that is provided from the external device via the magnetic field;
• switching, via the switcher, between an applied state in which a load of the variable resistor is applied to the resonance circuit, and a non-applied state in which the load is not applied to the resonance circuit, according to the response signal;
• and
• controlling, via the control circuit, a resistance value of the variable resistor according to a bleed power dissipated from the regulator, to generate the operating power.

A non-transitory computer-readable storage medium storing a program executable by a computer provided in a noncontact communication medium that performs communication with an external device in a noncontact manner via a magnetic field provided from the external device, to execute a modulation process,

• wherein the noncontact communication medium includes
• a resonance circuit that generates an alternating current voltage by resonating using an induced current induced in an antenna coil by the magnetic field acting on the antenna coil,
• a regulator that generates operating power for operating a processing circuit, from power based on a direct current voltage obtained by rectifying the alternating current voltage,
• a variable resistor connected to the resonance circuit, and
• a switcher,
• the processing circuit is configured to generate a response signal corresponding to a command signal that is provided from the external device via the magnetic field,
• the switcher is configured to switch between an applied state in which a load of the variable resistor is applied to the resonance circuit, and a non-applied state in which the load is
• not applied to the resonance circuit, according to the response signal, and the modulation process includes controlling a resistance value of the variable resistor according to a bleed power dissipated from the regulator, to generate the operating power.