| 摘要 |
PURPOSE:To evade beforehand the occurrence of the disabling of a communication due to the power interruption of a data carrier during a reading operation, regarding a data processor using a non-contact carrier to be used for the toll utilization, etc., of facilities or equipments. CONSTITUTION:When the control part 22 from a reader/writer 10 to a data carrier 20 decides the reception of a prescribed command, a preliminarily fixed pseudo random signal is returned from a pseudo random signal generation part 23. The correlation arithmetic part 13 of the reader/writer 10 determines a self-correlation peak value when the reference signal which is the same as the pseudo random signal of the data carrier 20 and a reception signal coincide, this self-correlation peak value is compared with the preliminarily fixed threshold in a comparison part 15, and a reading control part 12 executes the reading operation when the peak value becomes more than the threshold. |
