Simulation of Determining of Circular-Harmonic Filter Expansion Center and Order

A method of determining expansion center and expansion order is proposed in optical pattern recognition. To the reference image, choose an expansion center of one order, and works out optimal order by means of the expansion center. If the optimal order is equal to the selected order, the selected expansion center and order are the optimum; or else do it again choosing another order. Computer simulation results show that the method yields a sharper correlation peak, higher signal-to-noise ration and better correlation discrimination compared with the circular-harmonic filter.