摘要 |
<p>The present invention ecompasses a terminal device and method of powering a portable device therefrom, by transmitting in two modes of operation. In particular, the terminal transmits to the portable data device, in a first mode of operation (201), a power signal at a first level and a data signal using a first modulation format and a first bit rate. The terminal further transmits, in a second mode of operation (205), a power signal at a second level and a data signal using a second modulation format and a second bit rate. The terminal is capable of determining a requirement to change modes of operation (203) and changes modes in response to changing power requirements of the portable data device.</p> |