| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress interference of an answer signal in a radio authentication system for use to detect many users who carry transponders having passed through an arbitrary gate among a plurality of gates disposed in parallel, wherein a plurality of interrogators transmit interrogation signals including identification information (ID) on themselves to narrow authentication areas which are previously and individually set and a transponder entering one of the authentication areas is actuated in response to the interrogation signal to return a response signal including identification information (ID) on itself, so that the respective interrogators authenticate transponders entering the respective authentication areas. <P>SOLUTION: The interrogators transmit the interrogation signals S1 to S3 in the same timing, and the interrogation signals S1 to S3 include channel information to be used to send back the response signals R1 to R3 to the transponders having received the interrogation signals, together with the identification information on the interrogators, and channels (differing in frequency and modulation system) to be used are made different among the interrogators TX1 to TX3 which have authentication areas set closely to one another. <P>COPYRIGHT: (C)2008,JPO&INPIT |
