According to the invention, the undesired periodic noise is filtered out of the input signal during the digital signal processing , after {HEAD ~ the conversion} of the digital signal into {TAIL ~ the frequency domain} 
According to the invention , the undesired periodic noise is filtered out of the input signal during the digital signal processing , after { HEAD ~ the conversion } of the digital signal into { TAIL ~ the frequency domain }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL