Zhong Huang¹, Jian Su², Guangjun Wen¹, Wenxian Zheng³, Chu Chu¹, Yijun Zhang^4,*, Yibo Zhang⁵

CMC-Computers, Materials & Continua, Vol.61, No.1, pp. 399-408, 2019, DOI:10.32604/cmc.2019.05876

Abstract A priori knowledge of the number of tags is crucial for anti-collision protocols in slotted UHF RFID systems. The number of tags is used to decide optimal frame length in dynamic frame slotted ALOHA (DFSA) and to adjust access probability in random access protocols. Conventional researches estimate the number of tags in MAC layer based on statistics of empty slots, collided slots and successful slots. Usually, a collision detection algorithm is employed to determine types of time slots. Only three types are distinguished because of lack of ability to detect the number of tags in single time slot. In this… More >

Haipeng Chen¹, Kexiong Liu², Chunyang Ma³, Yu Han⁴, Jian Su^5,*

CMC-Computers, Materials & Continua, Vol.57, No.2, pp. 195-204, 2018, DOI:10.32604/cmc.2018.03592

Abstract Recently, object identification with radio frequency identification (RFID) technology is becoming increasingly popular. Identification time is a key performance metric to evaluate the RFID system. The present paper analyzes the deficiencies of the state-of-the-arts algorithms and proposes a novel sub-frame-based algorithm with adaptive frame breaking policy to lower the tag identification time for EPC global C1 Gen2 UHF RFID standard. Through the observation of slot statistics in a sub-frame, the reader estimates the tag quantity and efficiently calculates an optimal frame size to fit the unread tags. Only when the expected average identification time in the calculated frame size is… More >