摘要 |
<p>An impedance matching circuit (24) for matching the impedance of an antenna assembly of a portable phone to the impedance of a signal processing circuit (28) of the portable phone. In the impedance matching circuit (24), a detection means (28) detects a carrier frequency of the RF signal and generates a control signal representing a detected carrier frequency. A matching subcircuit (30) impedance matches between the antenna (10) and the signal processing circuit (28) based on the detected carrier frequency. The matching subcircuit (30) impedance matches the antenna (10) to the signal processing circuit (28) with respect to a frequency band of which center is substantially the detected carrier frequency. <IMAGE></p> |