| 摘要 |
PURPOSE:To eliminate nonlinear distortion resulting from the class 'C' amplifica tion of a transmission waveform by shaping the transmission output waveform according to the difference between the mean waveform of a prescribed number of transmission output waveforms and an ideal transmission waveform. CONSTITUTION:A detector 1 detects the transmission output of a class 'C' power amplifier 200 is extract the transmission output waveform. This waveform is inputted to an averaging device 4 through an AD converter 2 and an input buffer 3 to become the mean waveform of a prescribed number of waveforms. The mean waveform is inputted to a modulation waveform correcting device 5 together with the output of an ideal waveform memory and the output of a modulation waveform initializing device 7 to obtain the difference from the ideal modulation waveform. This difference is sent to a modulation part 100 through an output buffer and a DA converter 10 to correct the transmission output waveform. Consequently, the transmission waveform which has no nonlinear distortion is obtained without any secular change.
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