ECG Noise Sources and Various Noise Removal Techniques: A Survey

ABSTRACT Heart disease is one of the major causes of deaths worldwide. It is an equal opportunity killer which claims million lives annually. Doctors use electrocardiogram (ECG) to detect abnormal heart rhythms and to investigate the cause of chest pains. This test detects and records the hearts electrical activity. An ECG is nothing but a record of the strength and timing information of electrical signals as they pass through the heart. A common problem in ECG interpretation is the removal of unwanted artifacts and noise. There are various artifacts which get added in these signals and change the original signal therefore the need to remove these artifacts from the original signal is significant. An ECG signal consists of very low frequency signals of about 0.5 Hz-100Hz and digital filters are very efficient for noise removal of such low frequency signals.Cardiac monitors are the devices which provide a means to filter the ECG recording. Methods of noise filtering have decisive influence on performance of all ECG signal processing systems. This paper is intended to review different noise sources associated with ECG signal acquisition and processing along with a brief survey of various methods implemented to reduce the same. Keywords:ECG, Noise filtering,artifacts, digital filters.