Impulsive noise measurements and characterization in a UHF digital TV channel

Abstract

This paper presents the results of a study covering measurement and characterization of the wide-band impulsive noise present in a digital TV radio channel. Measurements were conducted at a frequency of 762 MHz in different outdoor and indoor environments using vertical and horizontal polarization. The measurement system was built on commercial equipment only. The calibration process, which is an important stage of this kind of measurements, is described. To analyze the measurements the impulsive noise has been modeled as a pulse train where the pulse amplitude, pulse duration and elapsed time between pulses are considered random variables. It has been found that the pulse duration and elapsed time between pulses is not dependent on the antenna polarization while the pulse amplitude is, especially in the case of the noise generated by a fluorescent lamp. It has also been found that the pulse duration of the noise measured in the outdoor environments presents some clustering features and is correlated with the pulse amplitudes. This correlation may be caused by a RF noise bandwidth that is larger than the bandwidth of the measurement system. The noise in busy streets presents larger pulse durations, larger amplitude, and shorter elapsed time between pulses that the noise measured in a pedestrian area. Several statistical tests have been done to find the distribution function that best fits these random variables. Power Rayleigh, lognormal, exponential, Poisson, and Gamma distributions have been tested. According to the assessment carried out, none of the distribution functions is adequate to model the pulse amplitudes or the elapsed time between pulses, while the pulse duration seems to be Gamma distributed.

Robust Nonparametric Cyclic Correlation-Based Spectrum Sensing for Cognitive Radio

“…To obtain a theoretical indication of the performance loss due to the spatial sign non-linearity for a complex Gaussian distributed signal, such as the OFDM signal, in additive white Gaussian noise (AWGN) channel, we have derived the 6 asymptotic relative efficiency (ARE) of the spatial sign cyclic correlation detector relative to the cyclic correlation detector of [10] for a complex normal distributed input signal.…”

“…The impulsive interference on a computer platform is well modeled by a symmetric alpha-stable distribution [8]. As an example of outdoor measurements in urban environments, impulsive noise measurements in a digital television band (10 MHz bandwidth with a central frequency of 762 MHz) have been reported in [6]. Typical man-made impulsive noise sources in urban outdoor environments are igniting car engines, power lines, and heavy current switches.…”

“…Typical man-made impulsive noise sources in urban outdoor environments are igniting car engines, power lines, and heavy current switches. For more experimental measurement results demonstrating the impulsive nature of man-made noise, see [4]- [6], and the references therein.…”

Shot noise in actual urban and industrial environments

“…In other publications the noise is sampled below the Nyquist limit [2,3], with the consequent undersampling problems. Only in [6] is the Nyquist limit met.…”

Numerical and Experimental Study on Three-Dimensional Localization For Ultra-Wideband Impulsive Noise Sources

“…In recent years, there has been an increasing concern about the interference of ultra-wideband (UWB) impulsive noise with communication systems, such as wireless communications [1,2], television and radio broadcasts [3][4][5], and so forth. Among others, more attention is paid to the EM interference of television and FM radio broadcasts.…”