| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a communication area formation system capable of ensuring accuracy of area determination for an electronic key in a simple circuit configuration.SOLUTION: A transmission antenna 11 is directly driven with a battery voltage by directly being connected to a battery 21. When receiving an electric wave transmitted from the transmission antenna 11, an electronic key 1 measures a reception signal intensity thereof and sends measured reception signal intensity data to a vehicle 2 as a reply. A battery monitoring unit 24 monitors a battery voltage at the time of electric wave transmission from the transmission antenna 11. An intensity correction unit 25 corrects the reception signal intensity data by adding or subtracting a correction value for a battery voltage fluctuation portion to/from the reception signal intensity data received from the electronic key 1. An area determination unit 26 performs area determination for the electronic key 1 by comparing the corrected reception signal intensity with a determination threshold value thereof.</p> |
