| 摘要 |
PURPOSE:To improve the reliability and to reduce power consumption by controlling the number of power amplifiers operated in parallel depending on weather. CONSTITUTION:Only the 1st power amplifier 113 is activated at fine weather and the 2nd power amplifier 114 is not activated and the amplifier current and voltage are interrupted. The transmission output at fine weather is stored in a power amplifier control section 143 in advance comprising a microprocessor, and the control is performed by detecting a part of the output branched by a coupler 140 connected to an output terminal 112 by a detector 141, converting it by a detected current converter 136 and returning it to a power amplifier control section 143 via an A/D converter 142. When the attenuation due to rainfall is large, the 1st power amplifier 113 is operated up to the saturated output and the level does not reach a required rainfall margin, the 2nd power amplifier 114 turned on in advance is operated at a certain rainfall attenuation level and switching devices 117, 118 are connected to the position B to attain parallel operation. |
