Wavelet neural network based fault diagnosis in nonlinear analog circuits1

The theories of diagnosing nonlinear analog circuits by means of the transient response testing are studied Wavelet analysis is made to extract the transient response signature of nonlinear circuits and compress the signature dada. The best wavelet function is selected based on the between-category total scatter of signature. The fault dictionary of nonlinear circuits is constructed based on improved back-propagation(BP) neural network Experimental results demonstrate that the method proposed has high diagnostic sensitivity and fast fault identification and deducibility.