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2 RFID System Physical Anti-Collision Experimental Verification
to judge the performance of the tag such as sensitivity, the performance of the five
tags is quite different from the measurement results, and the relationship between
the sensitivity of the tag group and the performance of the single tag group can be
studied as a group of experimental tags. According to the measurement results, the
five tags were numbered successively. The tag with the smallest reading distance was
No. 1, and the maximum number was No. 5. Among them, the No.1 tag has the worst
performance, and it is taken as the key tag in this experiment. The tags selected in
the experiment are shown in Fig. 2.3, and the measurement results of single tag are
shown in Table 2.1.
(3) Reading distance test
According to Eq. (2.2), the calculated results of sensitivity of each tag are shown
in Table 2.2. Among them, the electromagnetic wave in free space wavelength of
0.33 m, the RFID reader the transmission power of P t is 24 dBm, calculate generation
Fig. 2.3 Tag schematic diagram
Table 2.1 Single tag reading distance
Distance/m
No. 1
No. 2
No. 3
No. 4
No. 5
1
4.274
7.015
8.289
11.954
12.092
2
4.132
7.085
8.142
11.926
12.032
3
4.262
7.065
8.282
11.827
12.107
4
4.269
7.124
8.149
11.895
12.087
5
4.102
7.068
8.116
11.914
12.046
Average
4.208
7.071
8.196
11.903
12.073