Specifications

Chapter 11
Conclusion and System
Evaluation
Over five thousand lines of code were written for the four microprocessors
employed in the system. The prototype operates as expected: it is possible
to track the movements of a tag between RFID readers. Results are buffered
before being delivered via email. The system is stand-alone, not requiring
any existing inf rastructure bar GSM network coverage.
The modular design enables simple upgrading of any component without
requiring a s ystem redesign.
Battery backup enables the device to function normally for over a day in
the event of a power outage. This is extendible by adding additional battery
packs. The device is able to operate from a variety of power sources and so
can be placed anywhere on the island.
In order for the system to perform reliably, it was important to implement
extensive recovery methods in software — the GSM/GPRS network and
RFID systems are particularly error prone.
It was found that it is very difficult to achieve long read ranges with
passive RFID technologies and that these systems are not very reliable – tag
orientation was a particular problem. For installation on the is land, it is
thus critical that the antennae are installed at the correct height and with
the correct orientation. Opportunities exist to further optimise the RFID
portion of the project as detailed in Section 5.8.
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