Applet Description: 

This applet shows a demonstration of our location detection inside the test bed that we have developed.  In this demo, we configured our system to track a mobile user as he walked around on the 4th floor of the Photonic Building, Boston University. The black arrow >  represents the current position of the user.  The blue trail  >>>  left behind is just for reference.  Black boxes  represents 10 reference points on the test bed whereas green dots are the location of  4 transmitters. As the black arrow moves on the demo path, the applet calculates which region the arrow is in, and shows the appropriate box colored box to indicate that region. 

In this demo, we determine the region based on the number of packets received from each transmitter with the threshold of 15 packets. We update the user's location every 4 samples. If the decoding certainty is greater than 75%, the current location is shown as blue box  . Otherwise, the box is red .  The demo shows that our system always chooses the region which is close to the black arrow.  However, it will not always show the box which appears to be the closest if the user  is at the edge of a region.  The original applet runs on the AppletViewer. 

Source Code for Java Applet Available Here

Demo2path.dat Available Here

Note: The applet shown above has been modified to view on the Java-enabled browsers.