Removal of Baseline Fluctuation from Emg Recordings

1. Abstract: Appropriate cancellation of the baseline fluctuation (BLF) is an important issue when recording EMG signals as it may degrade signal quality and distort qualitative and quantitative analysis. We present statistical and filter-design approach for cancellation of the BLF based on several signal processing techniques used sequentially. The methodology is to estimate the spectral contents of the BLF, and then to use this estimation to design a high pass Butterworth filter by using Bilinear Transformation that cancel the BLF present in the signal. Two merit figures are devised for measuring the degree of BLF present in an EMG record. These figures are used to compare both methods which naively consider the baseline without any fluctuation i.e. constant potential shift. Applications of the techniques on real and simulated EMG signals show the superior performance of our approach in terms of both visual inspection and the merit figures.