A Passive UHF RFID System with Huffman Sequence Spreading Backscatter Signals

摘要

At present passive RFID standards, the tag collision problems are solved using time division multiple access technologies, including slotted ALOHA schemes and binary-tree search schemes. In order to accelerate an inventory process, a multiple access scheme that can identify more than one tag simultaneously is necessary. Considering the characteristics of a passive UHF RFID system, a novel passive tag backscatter scheme using Huffman spreading sequences is proposed, which can effectively improve an inventory process. The performances of several studied multiple access schemes are compared. Simulation results validate the performance enhancement of the proposed system.