The One-dimensional Bar Code Acquisition System Based On Zigbee Technology Research And Design

Bar code collection is an important means of enter information. One-dimensional bar code (1-D bar code) because of its high efficiency, easy to use and low cost, has been widely used in various areas such as business sector, postal sector, transport sector, pharmaceutical sector, industrial enterprises and so on. Due to a variety of harsh field environment, as well as some commodity’s particular package, the signal processing capabilities and application scope of bar code collection system is of a higher demand.1-D bar code collection system has been achieved by researching the principle of bar code scanning, analyzing the characteristics of1-D bar code signal, and designing the combining signal processing method of both the hardware processing and software processing. On the hardware side, the1-D bar code scanning control circuit, the laser control circuit, the signal acquisition circuit, the AGC(Automatic Gain Control) circuit, the differential operation circuit, the filtering and amplifying circuit, the digitizing circuit and the decoding circuit have been designed and implemented. Three types of digital filter, median filter, linear mean filter and EWMA(Exponential Weight Moving Average) filter, and their characteristics and their ability of filtering1-D bar code signal have been discussed. According to the composition and characteristics of the noise, EWMA filter has been designed to de-noise. To compensate for edge smoothing effect caused by Gauss Filtering of laser, edge enhancement algorithm and blind de-convolution have been discussed and an edge enhancement filter has been designed to de-blur. A block local decoding method has been introduced to improve the adaptability of decoding and similarity checking method has been applied to reduce the error rate.With the expansion of supermarkets, factories, warehouses and the development of modern logistics and e-commerce, it’s required high efficient and rapid collection of mass bar codes. Referencing to the existing wired and wireless bar code data transmission technology and considering the advantages and disadvantages of mainstream bar code data transmission technology and their application fields, they can not meet the rapid and efficient collection of mass bar codes, so ZigBee technology is applied to the bar code data transmission. A convenient, fast and efficient mass bar code collection system has been designed to improve the level of digital management of modern logistics and e-commerce. A demo project, bar code collection system based on ZigBee star network, has been implemented in this graduation project. As a simple bar code information collection network, it is allowed moving jobs and wireless bar code data transmission. A visual graphic interface on PC is designed to collect, aggregate, store and display the bar code information of each node.