Aperture Jitter of Sampling System in AWGN and Fading Channels

This paper examines aperture jitter of the sampling system and its effect on communication systems in the additive white Gaussian noise (AWGN) and fading channels. Previous studies have claimed that AWGN power is directly proportional to the jitter noise power. We demonstrate that the aperture jitter can influence the input signal of a sampling system but is independent of AWGN. The noise power, due to the aperture jitter in a frequency-nonselective slowly fading channel, is shown to be a function of the input signal, the aperture jitter, and the channel envelope. The frequency-selective slowly fading channel involves another parameter analyzable paths. The effect of the aperture jitter on the bit-error probability (BEP) of a binary-phase-shift-keying digital communication system is also considered. The received signal-to-noise ratio (SNR) is calculated first, and its probability density function is derived. Then, the average BEP is evaluated as a function of SNR. Simulation results indicate that the aperture-jitter noise severely degrades the average BEP by reducing the received SNR. The results of this paper can be used in designing a wideband or radio-frequency-sampling digital communication system