. Tag communication overhead: This metric is the average number of bits transmitted
by a tag in a frame. This in?¬‚uences the amount of power consumption. Due to lack
of power source in tags, this must be low.
The simulation setup is shown in Table 8.1. To avoid the reader collision problem [4], we
place readers in such a manner that their reading ranges do not intersect. To appreciate the
impact of tag??™s mobility, we de?¬?ne meter per frame (MPF). The MPF of tag ax, MPF(ax), is
given by
TABLE 8.1
Simulation Setup
Parameter Value
Simulation area 100 m3100 m
No. of readers 100
Identi?¬?cation range of the reader 3 m
No. of tags 1000
Tag ID Randomly selected 96 bit ID
Maximum meter per frame (MPF) 2 m=frame
Adaptive Tag Anticollision Protocols for RFID Passive Tags 151
MPF(ax) ??
ma(t1; t2)
Fp(t1; t2)
(m=frame),
where ma(t1, t2) is the distance that tag ax moves in the time interval [t1, t2] and Fp(t1, t2)
is the number of frames executed by protocol p in the interval [t1, t2]. By using MPF,
we can ensure that tree-based protocols recognize the same tags in a frame. In our
simulations, initial positions and destinations of tags are randomly selected under the
simulation area. A tag moves from its initial position toward its destination with MPF,
which is randomly selected from 0 to the maximum MPF. We run each simulation 50
times under the earlier parameters and investigate the average results for the performance
evaluation.
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