| 摘要 |
PURPOSE:To minimize the error of output power even when an input waveform changes by providing an averaging circuit to average the output voltage waveform of a detector and an effective value circuit to have a quick time constant at charging time and have a slow time constant at discharging time. CONSTITUTION:An effective value circuit 9 minimizes the difference between modulation and non-modulation when a modulated wave having a low bit rate is inputted by arbitrary changing the time constants for charging and discharging. Further, an averaging circuit 8 makes the waveform pass as it is at the time of the modulated wave having the low bit rate and averages the waveform at the time when the bit rate of the modulated wave becomes a high bit rate. The error of the output power can be minimized even when the input waveform changes from the modulation to the non-modulation or from one wave to plural waves in a wide range transmission speed without slowing the response speed of automatic power control by averaging the waveform with the above- mentioned two circuits 9 and 8. |
