The APD statistical analysis of the high-speed system electromagnetic noise
This paper mainly discusses the power network offline noise of high-speed railway system, and uses the MATLAB simulation analysis on its amplitude probability distribution. The results show that the characteristics of the noise mentioned in this article is consist with the theoretical model of the high-speed railway system. It can be used to study the effects of such noise on the high-speed system.
On the Relation Between the Amplitude Probability Distribution of Noise and Bit Error Probability
In the paper entitled "Relation Between the Amplitude Probability Distribution of an Interfering Signal and Its Impact on Digital Radio Receivers," a formula for estimating the bit error probability of an interfered digital wireless receiver was presented in terms of the amplitude probability distribution of the noise. This formula is very useful for predicting the impact of interfering signals on digital wireless systems and for defining appropriate limits for the interfering signal level to protect wireless systems. However, the formula must be corrected so that it is valid for modulation schemes, such as quadratic-amplitude modulation and multiple phase-shift keying.
Relation between the amplitude probability distribution of an interfering signal and its impact on digital radio receivers
New emission limit requirements are needed to protect digital communication systems from radiated interference. Traditionally, standard emission requirements have focused on protecting analog amplitude modulated radio services. However, developments in digital technology require emission limit requirements adapted to protect digital radio communication services. The amplitude probability distribution (APD) of the envelope or the quadrature components of an interfering signal has been shown to be related to the bit error probability of some digital radio receivers. However, a general description of the APD of an interfering signal and its impact on digital coherent radio receivers has not been presented. The aim of this paper is to clarify this relationship for a larger group of digital radio receivers. A method of incorporating the APD in conventional error expressions developed for digital coherent radio receivers in additive white Gaussian noise is presented. Furthermore, the relation between the maximum error probability for different digital modulation schemes and the APD is described, which allows definition of emission requirements on the APD