CONTACTLESS COMMUNICATION UNIT

摘要

PROBLEM TO BE SOLVED: To generate a magnetic field with a stable level independently of dispersion in am amplification factor of amplifiers and a difference from an installation environment or the like without the need for adjustment of the resistance of variable resistors different from a conventional communication unit in a contactless communication unit such as a reader/writer that makes contactless communication with a mobile information communication body such as an IC card by generating the magnetic field from a loop antenna. SOLUTION: In the case of contactlessly transmitting power and information from, e.g. the reader/writer to the IC card by generating the magnetic field from the loop antenna 7, a pickup coil 9 detects the magnetic field generated from the loop antenna 7 and an adjustment means consisting of a control section 12 and a power control circuit 3 or the like adjusts a level of the magnetic field generated from the lop antenna 7 to the prescribed level based on the level of the magnetic field detected by the pickup coil 9.