CPC H04W 4/80 (2018.02) [H02J 50/10 (2016.02); H02J 50/80 (2016.02); H04B 5/0025 (2013.01)] | 20 Claims |
1. A method, comprising:
detecting, by a first near-field communication device, the presence of a second near-field communication device;
detecting, with the first near-field communication device, whether the second near-field device is a first type of device configured to be charged by the first near-field communication device or a second type of device configured to exchange data with the first device;
if the second near field communication device is the first type of device:
adjusting, by a control device of the first near-field communication device, an impedance of an impedance matching circuit of a near-field communication circuit of the first near-field communication device from a first impedance value to a second impedance value by adjusting a capacitance of a variable capacitor; and
transmitting an electromagnetic field with an antenna of the first near-field communication device while the matching circuit is at the second impedance value;
if the second near-field communication device is the second type of device:
keeping an impedance of the impedance matching circuit unchanged; and
transmitting an electromagnetic field with the antenna while the matching circuit is at the first impedance value.
|