Study On Photoelectrical Banknote Counter System Based On DSP

For its mall size, small pixel dimension and high precision , the CCD (Charge Coupled Device) measurement technology can get high spatial resolution. It is noncontact, nondestructive, high-precision, high-speed and easily automatized, and its application is convenient, agile and adaptable. The signal of its exportation is apt to be digitized to constitute a real-time automatical measurement system. In the last few years, the CCD measurement technique has been broadly applied in every kind of realm for high-accuracy, high-speed measurement.At present the traditional banknote counter in the banknote mill which accomplish the counting by detaching new bill, has many shortages such as: the damage of new bill, the large quantity paper scraps of outgrowth , making noises and high labor strength. A new method used for banknote on-line counting is presented which is based on microscopic measurement and CCD measurement techniques.In the thesis, we have done some embedded research of the method of counting the new bill. By observing and studying the characteristic of edge outline of the newbill,a new optical method used for acquiring information from defocused image of new banknote is presented. An analytical description of the low-pass optical filtering performed by defocused imaging has been established.At the same time, we have accomplished research about the signal of the new bill in digital signal processing realm. Many kinds of DSP-oriented data processing methods are developed. The effectiveness and correctness of the new banknote recognition method are verified in experiment. According to the above solution and the technique of DSP, we accomplished the design for the banknote counter production.Compared with the traditional special banknote counter, the new counter has many advantages such as: noncontact, unabroken, higher precision, higher speed, environmental protection. The system that we designed has high works efficiency, operation convenience. It matches the instrument miniaturization and environmental protection development current.Finally, This paper presented the project of the further improvement of the system.