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4-1 Read/Write Antenna and ID Tag
4-3
• Communication area affected by the ground
If an antenna is installed near the ground, radio waves (microwave) emitted from the antenna and ones reflected by the ground overlap
each other. Therefore, an outline of the communication area becomes ragged and complex. In this case, dead zones may be formed fre-
quently, where no communication can be made to the tag.
Correct Usage
Depending on a working site, a special point may be generated in the communication area above and the communica-
tion to the tag cannot be made at the point. So, be sure to execute the communication check with a communication test
(refer to Section 3-5), etc.
Antenna
Tag
Ground
Tag
Antenna
Ground
Communication area affected by the ground
Communication area not
affected by the ground