Allflex RS340, User Manual

Page: 17 / 44

17
Factors that affect read range performance
Tag reader efficiency is often linked with reading distance. The Stick Reader's read
distance performance is affected by the following factors:
Transponder orientation - To obtain maximum reading distance, the axes of the
transponder and reader antenna coils must be optimally orientated as shown in Figure
2.
Transponder quality - Each manufacturer's transponder differs by (a) the level of
exciter signal energy required for the transponder internal circuits to operate
sufficiently, (b) the signal level of the ID code information that is returned to the
reader. Consequently, it is normal to find that common type transponders (for
example, FDX-B) from different manufacturers have different read range
performance levels.
Animal movement - If the animal moves too quickly, the reader may not be located in
the read zone long enough for the ID code information to be obtained.
Transponder type - HDX transponders generally have larger reading distances than
similar-sized FDX-B transponders.
Nearby metal objects - Metal objects located near a transponder or reader may
attenuate and distort the magnetic fields generated in RFID systems and therefore,
reduce reading distance. A good example being the eartag caught in a head bale
significantly reduces the read distance.
Electrical noise interference - The operating principle of RFID transponders and
readers is based on electromagnetic signals. Other electromagnetic phenomena, such
as radiated electrical noise from other RFID tag readers, or computer screens may
interfere with RFID signal transmission and reception and therefore, reduce reading
distance.
Transponder/reader interference - Several transponders in the reception range of the
reader, or other readers that emit excitation energy close by may adversely affect
reader performance or prevent the Stick Reader from operating.
Discharged battery pack - As the battery pack discharges, the power available to
activate the field becomes weaker and this reduced field results in a reduced reading
range.