XRAG2_08 Datasheet, PDF (20/33 Pages) STMicroelectronics – 432-bit UHF, EPCglobal Class1 Generation2 and ISO 18000-6C, contactless memory chip with user memory

Tag-to-reader protocol
XRAG2
6.1.6
Tag-to-reader Miller sub carrier modulation preamble
As for the FM0 base band modulation, the Tag supports the two Miller subcarrier
modulation preamble formats, according to the TRext parameter, as specified in the
EPCglobal Class 1 generation 2 RFID UHF specification, revision 1.0.9.
Figure 15 shows Miller preamble according to the value of the TRext parameter of the Query
command starting the inventory round.
Figure 15. Tag-to-reader Miller Preamble
Miller preamble (TRext = 0)
M=2
M=4
4M/LF
010111
M=8
4M/LF
0
1
0
1
1
1
Miller preamble (TRext = 1)
M=2
M=4
M=8
6.1.7
16M/LF
0 10111
16M/LF
0
1
0
1
1
1
16M/LF
0
1
0
1
1
1
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Tag-to-reader Miller subcarrier modulation end of signaling
In accordance with the EPCglobal Class 1 generation 2 RFID UHF specification, revision
1.0.9, the tag miller subcarrier modulation signaling ends with a dummy ‘1’. Figure 16 shows
the different possible Miller subcarrier modulation end of signaling sequences.
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