Adaptive Threshold Blanker in an Impulsive Noise Environment

This paper proposes a blanker with a threshold value that is adaptively updated based on average signal power in an impulsive noise environment. For conventional receivers, using a blanker as a preprocessor improves the bit error performance in an impulsive noise environment by removing received signal samples with large amplitudes in order to reduce the effect of impulsive noise. However, the conventional blanker shows a poor bit error performance in case of high signal-to-noise ratio (or large signal power) due to a fixed threshold. Therefore, the proposed blanker, called adaptive threshold blanker, overcomes this problem by adaptively updating the threshold and achieves an excellent bit error performance. In addition, this paper also introduces a simple method for calculating the quasi-optimal threshold value for the proposed blanker. This simple method allows an easy calculation of the threshold in practical systems. In order to evaluate the bit error performance of the proposed blanker, an approximated probability density function (PDF) using a sum of weighted Gaussian PDFs with different variances is also discussed. It is observed that simulation results agree well with the performance analysis.