Wireless communication between various « Mobile Communication Devices » (PDA, mobile
phone, laptop, connected devices, etc) or between the latter mentioned and a local network or
even the internet, have lead to a very strong need for a proper Connection Management.
Connection management consists of the assuring the good functioning of the whole of the
connections in their proper operating environment, and especially assuring the confidentiality
To meet these requirements, a clear view is needed on the characteristics of the
electromagnetic signal that supports each connection and one must be able to distinguish their
Nowadays, Bluetooth and Wi-Fi connections dominate this area.
Therefore, we plan to develop an apparatus that will help us to characterize the connections,
more specifically the transmitter power and the operating procedure (Bluetooth, Wi-Fi) of
Mobile Communication Devices.
Furthermore, if necessary, we should be able to generate interferences with our apparatus that
will disrupt the functioning of all Mobile Communication Devices within a specific range.
Firstly, we finished the study of the basic principles related to Bluetooth and Wi-Fi, as there
are: the most important modulation forms, different types of implementation, range,
frequency range, safety techniques and the coexistence between both.
In a next phase we started to develop a block scheme diagram.
As soon as we got the confirmation of functionality of our mentor we started looking for the
availability of practical components to realize a circuit diagram.
During this process we had to deal with a lot of problems because we needed a frequency
counter that accumulates the number of events occurring within a specific period of time.
The main problem was that this frequency counter was built on a microcontroller and we
couldn't figure out the code to program this controller. We did not have enough time to build
a program of ourselves. This period-time measurement is very important for the detection of
both Bluetooth and Wi-Fi signals.
A long search for a similar device for the detection was without result, so after some
discussion with our mentor he proposed to use an alternative block scheme diagram without
the use of a frequency counter.
Again we had to look for the availability of practical components to realize a circuit diagram
and discovered that this system wouldn't work without important problems. So the only
possibility for building our device was by the implementation of a microcontroller.
This brought us back to square one and went back to our initial block diagram. Fortunately for
us we could appeal on a senior-student's project who built a similar frequency counter and
therefore we had a similar code to program our controller.
This is just a tip of the iceberg regarding the problems we had to deal with, and that iceberg
really doesn't get any smaller when you opt for a foreign training period. On the other hand a
foreign training also has a lot of peripheral events and circumstances that make it a most
If you want to cite this thesis in your own thesis, paper, or report, use this format (APA):
DAUW, K., ACHTEN, C. (2006). Detecting and jamming mobile communication devices: WIFI and Bluetooth.
Unpublished thesis, Xios, IWT.