An Analysis of the Tolerance to Crosstalk Noise of a Pulse Width Modulation System
by D. I.-H. Park, R. D. Love
This paper reports the results of an investigation to determine the drive degradation caused by random noise in a pulse width modulation (PWM) system originally designed for communicating on coaxial cable but using instead twisted-pair cables. Presented are the analysis of the driver/receiver circuit, the theoretical modeling of the transmitted waveforms over the twisted-pair medium using ASTAP, and a methodology for trading off rms noise for transmission capability. The analysis of the effect of noise on drive distance as a function of allowable error rate is derived, and an example is provided. Finally, a simplified analysis technique is proposed to allow rapid calculation of approximate (yet conservative) results.