摘要 |
A wireless communications device includes a battery, a processing section coupled to the battery, and an RF interface. The battery is configured to provide power to operate the wireless communications device in a first mode of operation. The processing section is configured to operate on battery power in the first mode of operation. The RF interface is configured to receive an RF signal and generate operating power for the wireless communication device from the RF signal in a second mode of operation. The wireless communications device is configured to detect available RF power and enter the second mode of operation from the first mode of operation. |