Modernized artificial long line for pulse modulators
DOI: 10.31673/2412-9070.2021.054047
Abstract
The paper considers processes in artificial long lines, which are a constituent part of the pulse modulators for power amplifiers and generators. Analysis, which was carried out in the paper, shows that securing required form of the pulse during the artificial long line discharge over the matched impedance is the main problem in this line design and modernization. To study the form of the mentioned pulse, computer simulation of the processes in the line is used. The designed computer model of homogenous artificial long line allows one to establish that the output pulse of such a line during the discharge over the matched impedance has unwanted voltage overshoots and fluctuations at the beginning of the pulse top. It is known from different sources that revealed deficiencies of the pulse form can lead to the substantial deviations of the frequency and phase of the oscillations in the power amplifier that is fed by the modulator. To eliminate above-mentioned drawbacks, the paper proposes using damping resistor connected in parallel with the first inductance of the artificial long line and corresponding adjustment the value of the first capacitor of the line. By using designed model of the artificial long line, optimal values of the damping resistor and the first capacitor of the line were established, and it was revealed that proposed approach allows decreasing twelve times maximum relative deviation of the modulator pulse amplitude from the expected value. With account of the completed research, artificial long lines that are modernized in accordance with the proposed approach can be used in pulse modulators in telecommunication networks and radiolocation. They might be especially effective in those pulse modulators that supply power to the amplifiers with the strict requirements for the deviations of the voltage in pulse power supply.
Keywords: telecommunication networks; computer simulation; pulse modulator; artificial long line; amplitude fluctuations.
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