Wireless communication device and remote user interface device with automatic disconnect apparatus and method
A portable communication device, such as a cellular telephone, communicates via a wireless communication link with a remote user interface device, such as a hands-free interface. The portable communication device and the remote user interface device each comprises a motion sensor, by which each device can determine motion of the device with respect to the earth. The devices may share, via the wireless communication link, motion messages. The wireless communication link may be terminated as a function of the motion of the devices. After the wireless communication link is terminated, the remote user interface device may automatically enter a low-power mode.
1. A method executed by a processor in a remote user interface device, the remote user interface device comprising a motion sensor operably connected to the processor, the remote user interface device further having a wireless communication link with a portable communication device, the method comprising:
receiving a first motion message from the portable communication device, the first motion message indicating whether the portable communication device is in motion with respect to the earth;
receiving from the motion sensor a first motion signal, the first motion signal being a function of motion of the remote user interface device with respect to the earth;
determining, as a function of the first motion signal, that the remote user interface device is substantially stationary with respect to the earth;
determining, as a function of the first motion message, that the portable communication device is in motion with respect to the earth;
after a delay period, receiving a second motion message from the portable communication device, the second motion message indicating whether the portable communication device is in motion with respect to the earth;
after the delay period, receiving from the motion sensor a second motion signal, the second motion signal being a function of motion of the remote user interface device with respect to the earth;
determining that the remote user interface device is substantially stationary with respect to the earth as a function of the second motion signal;
determining that the portable communication device is in motion with respect to the earth as a function of the second motion message; and
thereafter terminating the communication link.
2. The method of claim 1 , further comprising, after terminating the communication link, entering a low-power mode.
3. A method executed by a processor in a remote user interface device, the remote user interface device comprising a motion sensor operably connected to the processor, the remote user interface device further having a wireless communication link with a portable communication device, the method comprising:
receiving a first motion message from the portable communication device, the motion message indicating whether the portable communication device is in motion with respect to the earth;
receiving from the motion sensor a first motion signal, the first motion signal being a function of motion of the remote user interface device with respect to the earth;
after an extended period of time of at least ten minutes, receiving a second motion message from the portable communication device, the second motion message indicating whether the portable communication device is in motion with respect to the earth;
after the extended period of time, receiving from the motion sensor a second motion signal, the second motion signal being a function of motion of the remote user interface device with respect to the earth;
determining that the portable communication device is substantially stationary with respect to the earth as a function of the first motion message and of the second motion message;
determining that the remote user interface device is substantially stationary with respect to the earth as a function of the first motion signal and of the second motion signal; and
thereafter terminating the communication link.
4. The method of claim 1 , wherein terminating the communication link comprises sending a request to the portable communication device to terminate the communication link.