Pulse­forming network with damping resistors

DOI: 10.31673/2412-9070.2022.014754

Abstract

The paper is dealing with the processes in pulse-forming networks, which are used in pulse modulators of different radio-technical installations. It is stressed, that the main problem that the designers of the pulse-forming networks face is to secure required form of the pulse under conditions of the network discharge over the matched load. In the previous paper, to improve the form of this pulse, it was proposed to use damping resistor connected in parallel to the first inductance. In this case, it was demonstrated that under optimal choice of the network damping resistor and the first capacitor parameters, maximum relative deviation of the modulator pulse amplitude from the expected value decreases approximately 12 times. In the current paper, to study possibilities of the further decrease of the relative deviation of the pulse amplitude from the expected value, it is proposed to also use damping resistor connected in parallel to the second inductance of the network. To perform the mentioned research, the previously developed computer simulation model was perfected with account of adding to the network diagram of the damping resistor in parallel with the second inductance. Trials of the improved computer simulation model with two damping resistors proved that while connecting the resistor in parallel to the second network inductance and tuning the value of the capacitor of the network, relative deviation of the pulse amplitude from the expected value decreases from 0.8 to 0.5 per cent. This pulse form amelioration appears to be sufficiently big, taking into account negligible cost of the elements that are added to the pulse-forming network. Proposed and researched with the help of developed and improved computer simulation model pulse-forming network can be used in pulse modulators of different radio-technical installations, in telecommunication networks and radiolocation. This is especially relevant for those pulse modulators that feed power amplifiers sensitive to the deviation of the voltage of the pulse power supply.

Keywords: telecommunication networks; computer simulation; pulse modulator; pulse-forming network; damping resistor.

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