User's Manual

User Guide

WherePort III User Guide D948 Rev B

3.3 Power Level

The size of the field is determined by the power setting for the WherePort. There are nine

power levels for the WherePort III. Setting the power level to 0 turns off the WherePort

magnetic field. Table 4 shows the approximate capture and release ranges for each of the

power levels when the tag’s orientation is random and when it is fixed as it moves

through the field.

Table 4 Power Levels, Random and Optimum Fixed Tag Orientations

Power Level Capture Range Release Range

Random Optimum

Fixed

Random Optimum

Fixed

0 Off Off Off Off

1 1.0 2.5 4.0 4.0

2 2.o 3.8 6.0 6.0

3 3.0 6 9.0 9.0

4 4.0 8 12.0 12.0

5 6.0 11 17.0 17.0

6 8.0 14 21.0 21.0

7 10.0 19 30.0 30.0

8 12.0 25 37.5 37.5

Random orientation means that the tag may take any of the possible positions relative to

the WherePort. Fixed tag orientation means that the motion of the object to which the tag

is attached will always present the tag in the same position relative to the WherePort. A

major difference between the random and the fixed orientation is the size of the

uncertainty area. It is significantly reduced when the tag has both a fixed and an optimum

orientation in the field.