Patent ID: 7834813

Claim:
A communications apparatus capable of transmitting and receiving signals in a plurality of frequency bands, the communications apparatus comprising: an antenna controllable to at least two resonant frequencies; a power amplifier for operating on an input signal to supply a first signal to the antenna for transmitting, a power-related parameter associated with the first signal, the power amplifier having an output power controllable responsive to the power-related parameter, wherein a power amplifier output impedance varies according to the output power; the antenna comprising an active element for transmitting signals supplied by the power amplifier and for receiving signals; the antenna further comprising controllable structural elements control over which determines the antenna input impedance and therefore the impedance into which the power amplifier operates, the structural elements controlled to increase a power amplifier efficiency; and an antenna controller responsive to the power-related parameter, or to the power amplifier output power, or to the power amplifier output impedance for controlling the controllable structural elements and for establishing an antenna resonant frequency from among the at least two resonant frequencies.