EXAMPLE8L.1有限长白噪声序列做试验 Consider a WGN sequence x(n).By using the randn function, 100 samples of x(n)with zero mean and unit variance were generated. From these samples,the autocorrelation estimates up to lag 40,denoted by (were computed using the autocorrelation function,from which the correlation coefficients (were obtained.The first 10 coefficients are shown in Figure 8.2 along with the appropriate confidence limits. Consider a WGN sequence x(n). By using the randn function, 100 samples of x(n) with zero mean and unit variance were generated. From these samples, the autocorrelation estimates up to lag 40, denoted by , were computed using the autocorrelation function, from which the correlation coefficients were obtained. The first 10 coefficients are shown in Figure 8.2 along with the appropriate confidence limits.  ˆ( )l EXAMPLE 8.1.1 有限长白噪声序列做试验  ( ) 40 l=0 r l