| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an inexpensive wireless transmission apparatus having a small area and low power consumption and capable of preventing a gain, a distortion characteristic or current consumption from being changed at a rear stage of a power amplifier depending on a load condition of an antenna, even if a load stabilizer such as an isolator is removed. <P>SOLUTION: An antenna load obtained from a power amplifier 100 is specified by prestoring a load-dependent characteristic of the power amplifier 100 in a memory 70 based on a detected transmission power level and a detected current value of the power amplifier 100. Based on a result of the above-described determination, a load adjustment of the power amplifier 100 is performed by a variable load unit 40 and a power source voltage adjustment is performed by a DC/DC converter 90, respectively. <P>COPYRIGHT: (C)2012,JPO&INPIT |
