Exploring aliasing distortion effects on regularly-sampled PWM signals

PWM based applications play now a very important role in supporting electrical power control and usage. Among all PWM techniques, regularly-sampled PWM is one of the most used pulse width modulation schemes. The popularity of this technique arises from the fact of its simplicity to be digitally implemented. From the historical point of view, regularly-sampled PWM was originally used in the aim of sinusoidal waveform generation. This paper investigates and discusses, through simulation, the effects of the aliasing distortion on the performance of regularly-sampled PWM in such cases in which this technique is used to represent modulating signals other than the sinusoidal. Moreover the paper suggests a solution for the problem and hence improves the performance of the produced PWM signal in these cases.

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