Wireless key system and key position discrimination method

Abstract

The present invention provides a wireless key system and a key position detection method that can accurately determine whether the wireless key is located inside or outside the main body through simple processing. The communication device provided in the main body transmits wireless signals through an internal antenna and an external antenna provided outside the main body and having a different directivity from the internal antenna; the wireless key receives the signal through any one of the plurality of antennas with mutually different directivities. When a wireless signal is transmitted from the communication device, the moving direction of the wireless key is measured, and the antenna that receives the wireless signal with the highest reception level is detected among the plurality of antennas as the first antenna. Based on the measured moving direction and the detected The directivity of the antenna, select an antenna with the same directivity as the internal antenna from multiple antennas as the second antenna, when the reception level of the wireless signal received by the second antenna is higher than the reception level of the wireless signal received by the first antenna When the level is high, it is judged that the wireless key is present in the main body.

Description

technical field [0001] The present invention relates to a wireless key system for performing wireless communication between a main body communication device installed in a main body such as a vehicle or a house and a movable wireless key. Background technique [0002] As one of the wireless key systems, there is known a technique in which the user moves with a wireless key (electronic key) and automatically locks / unlocks the vehicle door in such a way that the wireless key approaches a communication device provided on the vehicle door ( Refer to Patent Document 1). In such a wireless key system for vehicles, when the wireless key enters the surrounding area of ​​the communication device, wireless communication is performed between the communication device and the wireless key, and at the same time the communication device receives information including identification information transmitted from the wireless key through the wireless communication. Code (ID code) signal. Th...

AI Technical Summary

Problems solved by technology

However, in such a key position determination method, it is necessary to obtain data in advance, so there is a problem that processing becomes cumbersome.

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