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Ch66-I044963.fm Page 327 Thursday, July 27, 2006 12:15 PM
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Thursday, July 27, 2006
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Ch66-I044963.fm
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3.2 Read Range Measurements of Two Cartons
To study the effect of multiple carton identification on read ranges, the tags were identified in pairs
next to each other and on top of each other. The reading positions are shown in Tigures 7 and 8. Both
of the tags had to be read reliably at the maximum reading distance.

Vertical position Vertical position
Figure 7: Reading position with the cartons Figure 8: Reading position with the cartons on
next to each other top of each other

Tables 2 and 3 present the results of the read range measurements. Also in the case of two cartons the
identification cannot be carried out using folded dipole tag when the foils are in place in the packs. It
was also observed that the read range of the integrated patch-type tag dropped when two cartons were
read side-by-side or on top of each other. Tt can also be noted that when the cartons are on top of each
other and the foils are removed from the packs the integrated patch has longer read range. The patch-
type tag can exploit the packs as a substrate material, and therefore identification of two cartons on top
of each other is more reliable than when the folded dipole tag is used. The folded dipole tag does not
need a substrate material for functioning, and therefore the cigarette packs between the tags attenuate
the incident wave and thereby shorten the read range. In general it can be stated that increasing the
number of tags to be read simultaneously shortens the read range.

TABLE 2
MAXIMUM READ RANGE COMPARISON OF TWO CARTONS NEXT TO EACH OTHER

Cartons next to Packs with Packs without Empty carton
each other foils foils
0.50 m 1.20 m 1.20 m
Integrated patch
0m 1.80 m 1.80 m
Folded dipole