Calculating the Time Varying Signal Distribution and PAR in QAM Cable TV Systems

This paper was driven by the need to find the probability of rare peaks in cable TV systems. The paper presents a simple way of calculating the signal distributions. The method is much faster than running simulations. In the process some useful results about the time-varying statistics of the signal as well as the important role played by the pulse shaping filter are presented. The rare peaks are found to be less likely than what is predicted by assuming a normal distribution. Measurements and simulations that confirm the calculations are included.