| 摘要 |
<p>A dual-band mobile telephone system provided with an RF power module which operates at two different frequencies, wherein a common high harmonic control circuit which controls higher harmonic power in each of the frequencies at both bands is incorporated in the output circuit of the power module so as to improve the efficiency of the circuit. In addition, a means is provided for setting a bias by using a bias control signal outputted from the CPU of a control section interlocking with the frequency switching operation at the main body of the mobile telephone system so as to make the efficiency the maximum in response to an output power request from each communication system. A switching element is incorporated in the higher harmonic control circuit so that higher harmonics may be controlled without giving any influence to radio signals of each communication system. This constitution realizes a dual-band mobile telephone system which is reduced in size and improved in efficiency.</p> |
