ON Semiconductor AND9670/D Quick Start Manual page 6

RFID READER READING RANGE AREA
The maximum distance or the reading area of the RFID shield to the tag position depends on the reader antenna type and
the tag orientation itself regards to the reader antenna position. Due to different environment conditions, like the reflection of
the nearby objects causing multipath interference as well as influence of the human body holding the tag in the proximity of
the reader antenna, the maximum read range can vary and cannot be precisely predicted in advance.
The following chapter illustrates the different RFID reader range areas based on the evaluation results in an ordinary
environment.
The IDK RFID shield kit is provided with the helical whip antenna [3] with the omni−directional radiation pattern
characteristics.
The whip antenna is mounted on the left corner edge of the RFID shield as shown in the picture below which effects the
radiation pattern directivity due to the ground plane of the RFID shield itself.
Within the optimum reader reading range, up to 10 SPS tags can be detected as shown below.
The commonly used mounting position of the whip antenna are in horizontal and vertical plane with regard to the ground
plane.
In H−plane position, the antenna is mounted with the pointing position parallel to the earth ground floor as shown in the
Figure 8.
AND9670/D
Figure 8. Reading of 10 SPS Tags Simultaneously
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