Antenna Dynamic Tuning; Adjusting Antenna Output Power; Antenna Over-Current Protection And Dynamic Output Power - Biomark IS1001 Operation User's Manual

Installing and Configuring IS1001 Reader

Antenna Dynamic Tuning

When the antenna de-tunes it means its signal phase has deviated from the target value. During
system operation Dynamic Tuning tracks this phase deviation to determine when and what
adjustments to make to the tuning capacitors setting to return the phase value to the target value
and to re-tune the antenna. The adjustments are done gradually so there is no interruption of tag
detection. If there is an interruption in tag detection it is due to the antenna being too far out of
tune while Dynamic Tuning is making the necessary adjustments.
Since Dynamic Tuning has a finite range, not all changes in antenna tuning can be recovered
using electronically switched capacitors. With this in mind, it is recommended that you adjust the
capacitors at the antenna so that the initial tuning capacitance setting is as close to the mid-range
as possible.
There are customizable alarms available that can notify you in advance if your system is
approaching the limit of the Dynamic Tuning range. Alarms will also notify you if the antenna is
out of tuning range, and they will suggest the direction of changes to make to antenna capacitors.
The responsiveness (sensitivity) of the Dynamic Tuning can be adjusted by changing the
Dynamic Tuning Phase Deviation Threshold value. Dynamic Tuning will not attempt any tuning
capacitance adjustments until the phase deviation value exceeds the threshold setting in either
direction. This value is determined and set automatically during Antenna Full Tune process, but
can be adjusted afterwards, if necessary. For instance, for low Q systems where wider tuning
changes would not cause big detection losses or for systems with rapid and frequent conditions'
changes, the threshold setting can be set higher (10 or more) to reduce the unnecessary Dynamic
Tuning activity. But beware of setting the deviation value so low that the reader is not able to
maintain the tune point or so high that the IS1001 reader is not making any adjustments.

Adjusting Antenna Output Power

Note: This section does not apply to IS1001-12V readers because their exciter voltage is fixed at
10 V DC.
Antenna output power (current) can be adjusted by changing exciter voltage (VE Level) on
standard 24 V DC IS1001 readers. There are five steps of exciter voltage adjustments: from 12 V
DC to 20 V DC in 2 V increments. Therefore, setting "1" adjusts the exciter voltage to 12 V DC
(the minimum antenna power) and setting "5" adjusts the exciter voltage to 20 V DC (the maximum
antenna power).
It is recommended that you set antenna output power (current) to the lowest setting that provides
the necessary detection range.

Antenna Over-Current Protection and Dynamic Output Power

The IS1001 reader has a built-in antenna current limiting mechanism that will generate an alarm
message when an antenna current in excess of 10 A peak-to-peak is detected and will
automatically reduce the exciter voltage when an antenna current in excess of 11 A peak-to-peak
is detected in order to bring the later to an acceptable level. If an antenna current exceeds 11 A
peak-to-peak even at the minimal exciter voltage setting, the IS1001 reader will switch to Standby
mode until it is reset or toggled back to Scan mode.
If after the over-current protection had been activated and exciter voltage level had been reduced
to keep antenna current below 11 A peak-to-peak, the IS1001 reader detects antenna current
drop of more than 5%, the reader will return exciter voltage level to the original, defined by user,
setting in order to maintain highest acceptable antenna current.
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