IEC_TR_61282-10-2013_cor1-2013.pdf

April 2013 IEC/TR 61282-10(First edition 2013)Fibre optic communication system design guides Part 10:Characterization of the quality of optical vector-modulated signals with the error vector magnitude C O R R I G E N D U M 1 4.2 Normalization of the measured data Replace the existing text of the second paragraph by the following new text:The normalization factor is chosen to match the measured vectors to the reference by first finding the value of a scaling factor for the reference vectors that minimizes the corresponding unnormalized EVMrms without changing the distribution of the measured vectors.Then the inverse of is used as to scale the measured vectors to the normalized reference.For this purpose,the unnormalized EVMrms is expressed as ()()()()=nQnInnNUNnr(n)measmeasmeas12measref where1SSS(6)The value of that gives minimum U is determined by solving 0=U(7)leading to ()()()=+=NnnrrefnrNnnrnrnQQnIIQI1meas)(meas)(ref12)(ref2)(ref1(8)