TÜBİTAK-BİLGEM Shot Estimation System (SES)

In this work, design and experimental studies related to TUBITAK-BILGEM Shot Estimation System (AKS in Turkish) will be discussed. AKS is composed of three parts which are, a microphone array that has a specific structural design, an electronic unit that enables synchronous recording of the microphone signals and a graphical user interface that prompts the output of the system. Basic goal is to detect the position of a pre-defined sound source in terms of cartesian coordinates with respect to the original position of the system. First, the position of the sound source is detected in the cartesian coordinates by using only the time difference of arrival information. The time difference of arrival problem is solved using the generalized cross correlation function. In order to compensate for the false alarms that is very common in these systems, an energy based and a Mel Frequency Cepstrum Coefficients based two stage classifier is used. System is tested with shots from four different hand held rifles, from two different distances for each 10 degree angles spreading over 180 degrees. The average directional error for 100m shots is 2,69 degrees while the error declines to 1,51 degrees for 200m shots. The precision of the system is %84,6 while the recall is %96,2.