Inductive coupling for battery sharing and multi-function inductive antenna
A mobile device includes a housing and an antenna. The mobile device further includes a power-receiving circuit, and power-transmitting circuit, and a short-range communications circuit. The antenna performs multiple functions in that it is shared by the power-receiving circuit, the power-transmitting circuit and the short-range communications circuit. Each of the three circuits is selectively connectable to the antenna. The mobile device is configured to participate in a mobile-to-mobile battery-charge-sharing operation via inductive coupling from mobile device to mobile device.
1. A mobile device comprising:
a housing;
an antenna contained and/or supported by the housing and including a plurality of loops;
a power-receiving circuit contained by the housing, said power-receiving circuit selectively connectable to the antenna;
a power-transmitting circuit contained in the housing, said power-transmitting circuit selectively connectable to the antenna;
a short-range communications circuit contained in the housing and selectively connectable to the antenna, the short-range communications circuit for sending and/or receiving data communications signals via the antenna; and
switching circuitry coupled to the antenna, the power-receiving circuit, the power-transmitting circuit and the short-range communications circuit such that:
when the power-receiving circuit is connected to the antenna, the power-receiving circuit is effectively coupled to a first number of said loops of the antenna;
when the power-transmitting circuit is connected to the antenna, the power-transmitting circuit is effectively coupled to a second number of said loops of the antenna; and
when the short-range communications circuit is connected to the antenna, the short-range communications circuit is effectively coupled to a third number of said loops of the antenna;
said first, second and third numbers of antenna loops not all being equal to each other.
2. The mobile device of claim 1 , wherein the short-range communications circuit is configured to engage in data communications in accordance with the NFC (near field communications) standard.
3. The mobile device of claim 1 , wherein the antenna is a first antenna; the mobile device further comprising:
a second antenna contained and/or supported by the housing; and
a voice communications transceiver circuit contained in the housing and coupled to the second antenna.