| 摘要 |
<p>PURPOSE: To obtain a responder of the mobile body identification device in which a reception range is extended even under a low current consumption and high speed communication is realized. CONSTITUTION: When a signal level received by an antenna 101 is increased, the circuit is waken up, a level of a signal control line 1081 is set to a high level to set a resistance of a load resistor 1032 of a detection section l03a detecting a signal from an interrogator to a low resistance. Furthermore, a bias current is supplied to a detection diode 1031. When the resistance of the load gets smaller, a time constant is decreased to sharpen a rising of the signal, no change in the duty ratio is caused because the signal is amplified and an output with fidelity to the signal whose processing speed is increased is obtained and the responder suitable for high speed communication is realized. Furthermore, the detection diode 1031 receiving a bias current detects the signal at the characteristic region at which a high level detection signal is obtained, then an output with a large change is obtained and then the reception area is extended.</p> |
