Antenna device and communication device using antenna device

A communication apparatus that makes data communications with a contactless integrated circuit card by electromagnetic inductive coupling, the communication apparatus comprising:

• a loop coil for electromagnetic inductive coupling;
• a magnetic member disposed near a metallic member facing a main side of the loop coil, opposite to a side facing the integrated circuit card, and wherein the magnetic member has a specific permeability μ′ and product Ms·t of saturation magnetization Ms and thickness t thereof set based on a range set for facilitating communications with the contactless integrated circuit card;
• a modulating means for modulating data for transmission to the contactless integrated circuit card, the modular means having a predetermined carrier frequency and supplying modulated data to the loop coil;
• and
• a demodulating means for demodulating data received by the loop coil from the contactless integrated circuit card.