A Multi-Tag Emulator for the UHF RFID System

Radio-frequency identification technology has been booming over the past few years, and the corresponding product varieties and standards are becoming more and more widely available. It is important to test the products and standards before putting them on the market, but it is inconvenient to simulate the real environment to test the efficiency of a reader, because different tag distributions in varying applications will lead to different electromagnetic field intensity distributions. In this paper, based on the analysis of the responses of multiple tags and quantification of the response times, a multitag emulator is proposed that is capable of emulating the responses of multiple passive ISO/IEC 18000-6C tags. A verification system is set up, and the measurement results show that, based on the pipeline structure at the frequency of 40 MHz, the system can emulate 50 tags with a link data rate of 40 kb/s. This multitag emulator can be applied not only to verify the inventory and anti-collision algorithm but also to debug a reader. Compared to the conventional reading efficiency test method, the proposed method is capable of achieving the same goal and saving time and resources.