| 摘要 |
PURPOSE:To perform stable kdistortion compensation for a long time, by providing the level adjuster between the predistorter circuit for distortion compensation and the compensated amplifier, and controlling the level adjuster depending on the gain variation of the compensated amplifier. CONSTITUTION:The compensation amount is greatly varied with the gain and position variation of the compensated amplifier. For example, the region to realize the compensating amount more than 25 dB is within + or - 0.8 dB for gain variation and within + or - 2.5 degrees for the phase variation. Accordingly, the means compensating the gain variation of the amplifier at the input is very effective to the distortion compensation. The signal distributed from the disributors 21 and 22 is monitored with the gain variation detector 23 and the level adjuster 16 is controlled depending on the variation and the input level of the compensated amplifier 13 is controlled, allowing to cancel the gain variation. Further, the gain variation of the amplifier is due to temperature, the level adjustment due to temperature detection can also be effective. |
