Random noise characteristics of a pulse-length-modulated system of communication

The paper deals with a theoretical analysis of the random noise characteristics of a pulse-length-modulated system of communication. The result is demonstrated by two different methods, one of which is rigorous and based on the frequency spectrum of a rectangular pulse, while the other is an approximation based upon calculation of the average value of the pulse waveform, plus noise, integrated over a period of time that is short compared with a cycle of the a.f. cut off frequency.