| 摘要 |
PURPOSE:To improve cost performance by using a logical circuit as a pulse generating circuit, and thus realizing up to a DC area and eliminating the need for an expensive multiplying diode. CONSTITUTION:An input signal Fi is applied a Schmitt trigger circuit 5, where its waveform is shaped. A monostable multivibrator 6 is triggered by the output of the Schmitt trigger circuit 5 to generate pulses synchronizing with the input frequency signal Fi. Its pulse waveform is Fourier-transformed to calculate the N order higher harmonic output aN. Then, aN=2EdxsinNpid/Npid (where E is the amplitude of pulses), its maximum efficiency output point is pi/2, and the duty ratio (alpha) at this time is irepresented as 1/2N. Therefore, the constant of the monostable multivibrator 6 is so selected that the duty ratio (d) of output pulses is 1/2N, maximizing its output. The output signal of the monostable multivibrator 6 is applied to a band-pass filter 7 to select the Nth higher harmonic, which is amplified by an amplifier 8 and outputted as a multiplied wave NFi. |
