NONCONTACT COMMUNICATION MEDIUM, MAGNETIC TAPE CARTRIDGE, OPERATION METHOD OF NONCONTACT COMMUNICATION MEDIUM, AND PROGRAM

A noncontact communication medium includes a power generator that has a coil and generates power with application of an external magnetic field from an outside to the coil, a clock signal generator that generates a clock signal using the power, a processor that operates using the power and executes processing on a command included in the external magnetic field. The clock signal generator makes a frequency of the clock signal lower as intensity of the external magnetic field is smaller, in a period except for a processing period in which the processor executes the processing.