Omron V680S Series User Manual page 208

Section 8
Appendices
 Travel Speed Calculations
When communicating with a moving RF Tag, specify an AUTO mode.
The maximum speed for communicating with the RF Tag can be calculated simply using the following
formula.
Maximum speed =
D (Distance traveled in interrogation zone) is calculated from the actual measurement or the
interrogation zone between the Reader/Writer and RF Tag.
 Calculation Example
The following example is for reading 128 bytes with the V680S-D2KF68, and V680S-HMD66-ETN.
From the above chart,
Distance traveled in interrogation zone = 170 mm when Y (communications range) is 50 mm
Communications time T = 123.98 ms (calculated from the communications time , i.e., 0.82 128 bytes + 19.02)
Therefore, the maximum speed of the Tag is as follows:
Maximum speed =
RFID System
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User's Manual
D (Distance traveled in interrogation zone)
T (Communications time)
Y
Movement
D
direction
Y
200
150
100
50
-250 -200 -150 -100 -50
170mm
D (Distance traveled in interrogation zone)
T (Communications time)
X
Interrogation zone
Y
X
0 50 100 150 200 X
170(mm)
=
123.98(ms)
= 82.27 m/min