| 摘要 |
<p>PURPOSE:To achieve a transmission with limited distortion in amplitude and phase at a grade-C amplifier by inserting a dummy pulse into a gap, the head or both of a plurality of subpulse trains when the subpulse trains are transmitted at each repetition cycle. CONSTITUTION:Outputs of oscillators 1, 2 and 9 with frequencies fA, fB and fC are modulated with modulators 3, 4 and 10 of a timing generator 5 to create subpulses PA and PB and a dummy pulse PD. It is necessary to provide a gap DELTAT between the subpulses PA and PB larger than a response time to a phase shifter or a variable attenuator 7. The dummy pulse PD is intended to fill the gap and a pulse width tau thereof is selected to be a value as closer as possible to the DELTAT within such a range as not to cause a cross modulation with the subpulses. These pulses are synthesized with a power synthesizer 6 and amplified with a grade-C amplifier 8 to be outputted. This allows the amplifier to perform the amplification with these pulses regarded as one pulse, thereby reducing a distortion in amplitude and phase.</p> |
