关键词: 电子警察, 车牌识别, 人工神经网络

Abstract: License plate recognition is an important function module of E-police system. Character recognition is a key step in the process of license plate recognition. Currently, BP（Back Propagation） artificial neural network is widely used in vehicle license plate recognition because of its superior performance. However, the BP network has some disadvantages, such as the local minimum, false saturation and slow convergence. According to these drawbacks of BP networks, an optimized BP artificial neural network is built to identify characters from the aspects of the layers of network, nodes number, momentum, learning factors. The results show that the algorithm has good performance and satisfies the application required.

Key words: E-police, license plate recognition, artificial neural network