| 摘要 |
In a keyless entry system including an in-vehicle device, and a portable device operated by a built-in battery, a request signal is transmitted from the in-vehicle device to the portable device so that wireless communication is performed between the in-vehicle device and the portable device, the portable device can set first sensitivity that is predetermined sensitivity and second sensitivity that is higher sensitivity than the first sensitivity and at which a detection area for the request signal is wide, as detection sensitivity for detecting the request signal, sets the detection sensitivity to the second sensitivity when determining that the portable device is in the vehicle's interior or within the predetermined distance from the vehicle, and sets the detection sensitivity to the first sensitivity when determining that the portable device is not in or comes to be not in the vehicle's interior or within the predetermined distance from the vehicle. |
| 主权项 |
1. A keyless entry system comprising an in-vehicle device mounted on a vehicle and a portable device carried by a user, wireless communications being performed therebetween by transmitting a request signal from the in-vehicle device to the portable device and an answer signal from the portable device to the in-vehicle device in response to the request signal,
wherein the portable device includes:
a built-in battery; anda control unit configured to switchably set a detection sensitivity for detecting the request signal between a first sensitivity and a second sensitivity higher than the first sensitivity based on an intensity of the request signal received, the second sensitivity providing a detection area wider than that of the first sensitivity, the control unit setting the detection sensitivity to the second sensitivity if it is determined that the portable device is inside or within a predetermined distance from the vehicle, and setting the detection sensitivity to the first sensitivity if it is determined that the portable device is not or will not be inside or within the predetermined distance from the vehicle, wherein the in-vehicle device transmits the request signal when an operation of opening a door of the vehicle is performed from inside the vehicle, followed by an operation of locking the door of the vehicle from outside the vehicle, and wherein the portable device performs authentication of the request signal received, and if the authentication is successful, determines that the portable device is away from the vehicle by the predetermined distance or greater and sets the detection sensitivity to the first sensitivity. |
