ADAPTIVE LINE ENHANCEMENT IN PRESENCE OF IMPULSIVE AND GAUSSIAN NOISES

Document Type : Original Article

Authors

1 Ass. Prof Military Technical College

2 Prof. Dr., Military Technical College

3 Ass. Prof., Military Technical College

4 Ph. D. Student, Military Technical College

Abstract

In this paper, a proposed scheme for an adaptive line enhancement (ALE) in presence of impulsive and Gaussian noises is presented. The proposed scheme is composed of an adaptive line enhancer and a median filter. The object of this scheme is to obtain a best estimate of the desired signal which is combined with an additive impulsive and Gaussian noise at very low input signal to noise ratio. The median filter is used mainly to remove the impulsive noise from the input observation. The resulting signal is applied to the adaptive line enhancer to obtain a good estimate of the desired signal. The adaptive line enhancer is implemented by an adaptive transversal filter whose output is assumed as a good estimate of the desired signal based on the minimization of the mean square error criterion. The filter coefficients are updated according to the least mean square (LMS) adaptation algorithm. The performance of the proposed scheme is evaluated in presence of the impulsive and Gaussian noise. It is concluded that using the adaptive line enhancer and median filter exhibits a better performance than that of the stand alone adaptive line enhancer.

Keywords