Abstract—SCADA systems are widely used by numerous industries
in order to control a variety of processes. During
the development of such a system, one is faced with several
challenges concerning reliability, security and congestion control.
For example, in a traffic light application, systems to handle
reliability and congestion control have to be carefully designed, in
order to meet the high safety requirements. In other applications,
especially wireless, security is of great importance.
This report is aimed to describe and address a few of these
challenges, but does so in a scaled down version. This project is
part of a larger activity with the overall purpose to navigate a
ground vehicle from a control station and provide an operator
with visual information. The work covered in this project will
focus mainly on implementing reliable data transfer over a
ZigBee radio link and on creating an adaptive protocol for
efficient transmission of images.
To make the existing software more robust to link congestions
and faults, we develop methods to handle lost data packets and
packet duplication. Additionally, we implement the capability of
image transmission from the vehicle to the control station that
makes use of an adaptive quality selector especially designed to
not interfere with the ability to control the vehicle.
—SCADA, radio transfer reliability, congestion control,
automatic repeat-request, selective repeat
2013. , 7 p.