| 摘要 |
PURPOSE: To extend a communication distance between an IC card and a reader/ writer without causing side reaction. CONSTITUTION: Three loop antennas L1, L1' and L1" which constitute an antenna radiating a magnetic field are arranged on the same plane so that there center parts are matched with each other. Current I1, I1' and I1", the number of turns N1, N1' and N1" and areas S1, S1' and S1" are set so that an expression (N1×I1×S1+N1'×I1'×S1'+N1"×I1"×S1"=0) is satisfied when N1, N1' and N1" are defined as the number of the turns of the loop antennas L1, L1' and L1", S1, S1' and S1" are defined as the areas (cross sections) of the loop antennas L1, L1' and L1" and current flowing through the loop antennas L1, L1' and L1" are defined as I1, I1' and I1".
|
