Chapter 9 - A Comparison of TTF and RTF UHF RFID Protocols

Figure 9.1 Tag transmissions operating under a free-running TTF protocol Reader Collision between transmissions No collision between transmissions

Figure 9.2 Description of dynamic changing of the waiting period under the Supertag protocol Overcrowded tags Less congestion Tag1 Tag2 Tag3 Van Eeden HL. Passive UHF RFID systems. Ph. D. thesis. Northwest University, Potchefstroom. South Africa. 2004. Tag4 Tag5 Reader Slow down instruction Acknowledgement Collision between transmissions No collision between transmissions

Figure 9.3 Switch-off Supertag protocol sequence Van Eeden HL. Passive UHF RFID systems. Ph. D. thesis. Northwest University, Potchefstroom. South Africa. 2004. Tag5 Reader Switch off instructions Collision between transmissions No collision between transmissions

Table 9.1 Different implementations of the IP-X protocol Protocol version Baud rate Maximum Interval V1 64k 4k V2 16k V3 256k V4 V5

Figure 9.4 iP-X R/W protocol flow diagram Yes Boot Power-on reset Wait random time Transmit ID Reader command? Correct ID? Wait command time Execute command No Van Eeden HL. Passive UHF RFID systems. Ph. D. thesis. Northwest University, Potchefstroom. South Africa. 2004.

Figure 9.5 Average reading time distribution for the Supertag Free-running protocol 10 tags, 64k baud rate, 64k interval) generated using a protocol simulator, with 1,000 samples, resulting in average read time of 172.7 ms, longest read time of 480.9 ms and standard deviation of 70.2 ms Van Eeden HL. Passive UHF RFID systems. Ph. D. thesis. Northwest University, Potchefstroom. South Africa. 2004.

Figure 9.6 Average reading time distribution for the Supertag Switch-off protocol 10 tags, 64k baud rate, 64k interval) generated using a protocol simulator, with 1,000 samples, resulting in average read time of 107.0 ms, longest read time of 1030.4 ms and standard deviation of 52.6 ms Van Eeden HL. Passive UHF RFID systems. Ph. D. thesis. Northwest University, Potchefstroom. South Africa. 2004.

Figure 9.7 Average reading time distribution for the Supertag Fast Switch-off protocol 10 tags, 64k baud rate, 64k interval) generated using a protocol simulator, with 1,000 samples, resulting in average read time of 72.6 ms, longest read time of 138.9 ms and standard deviation of 8.1 ms Van Eeden HL. Passive UHF RFID systems. Ph. D. thesis. Northwest University, Potchefstroom. South Africa. 2004.

Figure 9.8 Protocol saturation in TTF protocols Van Eeden HL. Passive UHF RFID systems. Ph. D. thesis. Northwest University, Potchefstroom. South Africa. 2004.

Figure 9.9 Error rates for TTF protocols Van Eeden HL. Passive UHF RFID systems. Ph. D. thesis. Northwest University, Potchefstroom. South Africa. 2004.

Figure 9.10 Average reading times for different implementations of the iP-X protocol Van Eeden HL. Passive UHF RFID systems. Ph. D. thesis. Northwest University, Potchefstroom. South Africa. 2004.

Figure 9.11 Maximum reading rates for the iP-X protocols Van Eeden HL. Passive UHF RFID systems. Ph. D. thesis. Northwest University, Potchefstroom. South Africa. 2004.

Figure 9.12 Maximum tag speeds for the iP-X protocol Van Eeden HL. Passive UHF RFID systems. Ph. D. thesis. Northwest University, Potchefstroom. South Africa. 2004.

Figure 9.13 Average repeat rate of tag backscatter transmissions Naudé CC, Marais HJ. Degradation in read performance with an increase in the number of user data pages. Internal research report. Faculty of Engineering. Northwest University, 2008.

Figure 9.14 Degradation of read performance Naudé CC, Marais HJ. Degradation in read performance with an increase in the number of user data pages. Internal research report. Faculty of Engineering. Northwest University, 2008.

Figure 9.15 State diagram for the IP-X free-running TTF protocol Van Eeden HL. Passive UHF RFID systems. Ph. D. thesis. Northwest University, Potchefstroom. South Africa. 2004.

Figure 9.16 State diagram EPC™ Radio Frequency Identity Protocols. Class-1 Generation-2 UHF RFID. Protocol for Communications at 860 – 960 MHz. Version 1.0.9. January 2005.

Figure 9.17 Spectrum of a Miller-encoded EPC reader Impinj Inc.

Figure 9.18 Total number of EPC tag singulations for different link rates

Figure 9.19 Number of tags detected from population of 4 using EPC Gen 2 with different link rates

Figure 9.20 Comparison of EPC and IP-X in terms of total number of tag singulations