Power spectrum density test If the process x(n)is white Gaussian noise(WGN),then the random variables ()=1,2,.K,are independently and uniformly distributed in the interval(0,1),and the plot should be approximately linear with respect to k.The hypothesis is rejected at level 0.05 if (k)exits the boundaries specified by i(k) 7()=长±1.36(K-) 1≤k≤K K-1 (8.1.5)If the process x(n) is white Gaussian noise (WGN), then the random variables are independently and uniformly distributed in the interval (0,1), and the plot should be approximately linear with respect to k. The hypothesis is rejected at level 0.05 if exits the boundaries specified by I k k K ( ) 1 2  =    I k( ) Power spectrum density test I k( )