Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Bit Level Synchronized MAC Protocol for Multireader RFID Networks | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2010 Article ID 956578 15 pages doi 2010 956578 Research Article Bit Level Synchronized MAC Protocol for Multireader RFID Networks Vinod Namboodiri and Ravi Pendse Department of Electrical Engineering and Computer Science Wichita State University Wichita KS 67260 USA Correspondence should be addressed to Vinod Namboodiri Received 27 July 2009 Revised 24 June 2010 Accepted 12 July 2010 Academic Editor Christian Hartmann Copyright 2010 V. Namboodiri and R. Pendse. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. The operation of multiple RFID readers in close proximity results in interference between the readers. This issue is termed the reader collision problem and cannot always be solved by assigning them to different frequency channels due to technical and regulatory limitations. The typical solution is to separate the operation of such readers across time. This sequential operation however results in a long delay to identify all tags. We present a bit level synchronized BLSync MAC protocol for multi-reader RFID networks that allows multiple readers to operate simultaneously on the same frequency channel. The BLSync protocol solves the reader collision problem by allowing all readers to transmit the same query at the same time. We analyze the performance of using the BLSync protocol and demonstrate benefits of 40 -50 in terms of tag reading delay for most settings. The benefits of BLSync first demonstrated through analysis are then validated and quantified through simulations on realistic reader-tag layouts. 1. Introduction A Radio Frequency Identification RFID system consists of one or more readers whose goal is to interact with small low-cost tags in their field. Each tag
