| 摘要 |
<P>PROBLEM TO BE SOLVED: To realize various types of near-field communication according to needs. <P>SOLUTION: In a near-field communication method, when an RF field is not detected within a predetermined time T<SB>IDT</SB>+n×T<SB>RFW</SB>, an NFC communication apparatus 1 being an initiator, starts outputting electromagnetic waves, activates an NFC communication apparatus 2 being a target, and transmits a request via a first electromagnetic wave resulting from modulating electromagnetic waves by means of transmission data. When communication of an active mode is started and the RF field is not detected within a predetermined time T<SB>ADT</SB>+n×T<SB>RFW</SB>, the NFC communication apparatus 2 starts outputting electromagnetic waves, and transmits a response to the request via a second electromagnetic wave resulting from modulating electromagnetic wave by means of transmission data. When communication of a passive mode is started, the NFC communication apparatus 2 transmits a response to the request by applying load modulation to the electromagnetic wave from the initiator. The near-field communication method can be applied to, for example, an IC card system. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
