The impact of communications channel bandwidth on the accuracy of pulse-width signal transmission

Abstract

Pulse-width modulation (PWM) signals used in various areas are sent to the receiver through a communications channel that distorts their waveform due to the limitations of the frequency range. It is not always possible to reduce additive (fluctuation) noises that are also present within the PWM signal to negligible levels. Limiting the range of frequencies transmitted over a communications channel results in both the deterioration of PWM signal front slopes and the changes in the spectral specifications of the fluctuation noise. The simulation of pulse signal formation helped identify a correlation between the pulse front slope and the number of harmonic components transmitted over the communications channel. Through the analysis, we established a correlation between pulse time and the additive noise parameters along with the bandwidth of the real communications channel. These calculations might be useful for problems where it is necessary to formulate the requirements for the communications channel transmitting the PWM signal.