Preliminary analysis of warehouse localization systems based on RFID technology

In the industrial warehouse design domain, today's computerized information systems have gained a relevant interest due to the issues related to asset tracking and traceability. In such context, the employment of newinformation technologies onwarehouse management systems has opened new business opportunities due to the sensible price reduction in the last years. This paper focuses on the technical issues related to the realization of wireless localization systems for warehouses, which are necessary for the implementation of random allocation policies, and in particular investigates the opportunities offered by RFID technology in such context. The enforcement of random allocation policies allows to increase the utilization coefficient of warehouses which is a critical issue, for example in refrigerated warehouses for perishable products. In particular, the development of localization systems based on trilateration is here considered, and an experimental model which links the received signal strength to the reading distance has been determined in order to take into account the specific features of the technology employed. A methodology is hence proposed to overcome the simplifying assumptions theoretical attenuation models rely on, by fitting a mathematical model on experimental observations. The problem of the accuracy level required to locate Stock Keeping Units (SKUs) of fixed dimensions is also considered, resulting in the evaluation of the maximum allowed reading distance. On the basis of the obtained results, the optimal configuration of the fixed infrastructure in terms of the number of antennas and their position is finally defined.