Hi Pradeep,

The answer is...it depends. It depends on what you want to do with your rectified signal. The absolute (ABS) will  only put all your negative values positive. The ARV will also do that but will add another treatment as doing the mean over a time window (0.1 second by defaut) so your rectified signal will also be smoothed. Usually, we're doing some smoothing after rectifiying the EMG so the ARV might be a good approach in this case by choosing the appropriate time window. Anyway, if you choose either type of treatment, be sure to remove any DC offset from your EMG (even if there's not suppose to be one...ideally) by substracting the mean of your raw signal first or doing a highpass/bandpass filter on it before applying the rectification.

Hope this helps,

Michel

I suppose above answer covers your query. Only thing i wish to add is that ABS will give you output like full wave rectification.

Thank you Ajat and Michael Goyette.. Your answers and response were helpful..