| 摘要 |
A radio IC tag reader comprises: a first variable frequency oscillation section for generating a signal having a frequency meeting a unit radio channel used for transmission/reception to/from a radio IC tag; transmission and reception sections for executing transmission/reception to/from the radio IC tag by using the signal; a second variable frequency oscillation section for changeably generating a signal of a frequency meeting a unit radio channel for measuring the strength of a received electric wave; a carrier sense executing section for measuring strength of a received electric wave in each of the unit radio channels by using the signal; and a main control section for controlling the first variable frequency oscillation section so as to generate a carrier signal having a frequency meeting the next unit radio channel used by the transmission and reception sections based on a result of measurement by the carrier sense executing section, upon passage of a continuous transmittable time after start of transmission/reception.
|
