Abstract:This paper puts forward a new method of analog circuit fault diagnosis based on the combination of wavelet packet decomposition, the normalized processing, GAPSO and BP neural network. The method, adapting wavelet packet decomposition, obtains each scale energy characteristics information from function space as its vector to put in the neural network. It uses GAPSO to optimize the weights and thresholds of BP, which can effectively overcome the defects of BP neural network such as easy to fall into local minimum. Taking Multisim simulation circuit as an example, the effectiveness of the proposed method is verified by the comparing of the GAPSO-BP and BP result.