An Efficient Protocol Of Queries For Large And Small Categories In RFID Systems

With the development of the Internet of Things technology,sensor networks are gradually becoming industrialized.Among them,the application of RFID technology as the core technology of the Internet of Things is also becoming more and more widespread.For example,warehouse management,anti-counterfeiting and target tracking.In recent years,categorized RFID systems have attracted extensive attention from the academic community to the industrial community.In warehouse management,goods are divided into multiple categories based on information such as different brands or manufacturers.Although there are too many categories in a large-scale categorized RFID system,the information of only a few categories may be frequently collected in some applications.For example,a manager often needs to query the large categories and small categories in the warehouse to determine which types of goods need to be replenished,and which need for sales promotion.The existing protocols are inefficient in solving large categories and small categories queries.In this paper,we propose a new protocol called Query for Large categories and Small categories(QLS),which can find the large and small categories in RFID systems efficiently and accurately.The protocol uses multiple hash pairs to allocate as many tag categories as possible to slots,which effectively improves the utilization rate of the time frame.At the same time,the reader uses a combined signal in each slot to estimate the size of the tag categories.Obtain large categories and small categories by comparison with the threshold.In addition,we analyzed the efficiency of the assignment algorithm and optimize the parameters k through theoretical analysis to minimize the execution time of the protocol.In the experimental part,we compare the execution time and Accuracy of the QLS with other protocols through simulation.A large number of simulation results show that the QLS protocol is superior to other protocols.Specifically,when the length of SOG is 32 bits,it reduces nearly 24%of the required execution time compared with Top-k protocol,and reduces 77%of the required execution time compared with ART protocol.