Reading Rate Improvement for UHF RFID Systems with Massive Tags by the Q Parameter

• Published in: Wireless personal communications Vol. 59; no. 1; pp. 147 - 157
• Main Authors: Luh, Yuan-Ping, Liu, Yin-Chang
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.07.2011
• Subjects: Communications Engineering; Computer Communication Networks; Engineering; Networks; Signal,Image and Speech Processing; Reading rate; UHF; Massive tags; Q parameter; Signal collision
• ISSN: 0929-6212; 1572-834X
• DOI: 10.1007/s11277-010-0198-y

To implement an ultra high frequency (UHF) RFID system, the first problem that an enterprise faces is the assurance of stable and extremely high reading rates. Empirical investigations indicated many hardware and environment factors can affect the reading rates. Unfortunately, even if all of the hardware and environment factors have been resolved, reading a large number of RFID tags in a single run is still a challenge. For RFID systems with massive tags, signal collision is the major factor to reduce system reading rate. To diminish the influence induced by signal collision, this study examined the anti-collision technology applied in EPCglobal UHF Gen II standards and proposed the method of adapting the Q parameter of control module in UHF RFID interrogator. Finally, we conducted field simulation to monitor relative reading rates under different conditions with different tag numbers, speeds passing through portal and Q values. Following by experimental results, this study provided the criteria to determine optimal Q value by activating system. With proper Q value, stable and extremely high reading rates in one-time reading of a large number of RFID tags (100 and above) can be achieved.