Shotspotter: Acoutic Gunshot Positioning

Shotspotter, inc, a Mountain View, CA based company has an interesting technology that uses microphones placed in an area such as a city neighborhood or a military combat area that can be used to automatically detect and triangulate the position of gunshots. Conceptually, of course, this is not difficult, but the devil is in the details, and they claim to be able to do things such as automatically ignore sounds like cars backfiring. They also claim their triangulation algorithms are robust against interference such as echos that I imagine plague their microphones in urban environments. Whether this requires calibration for each setup is unclear to me from their website, but even so, it would be am impressive feat -- echos off of large buildings can often be louder than the original sounds.

They also say a lot of analysis can be made based on data collected from even sparsely placed microphones, and give an example:

ShotSpotter sensors detect gunfire at a range of one to two miles away from the sensors, and ShotSpotter systems have been shown to be accurate to within 25 meters over one to two mile ranges.

In addition, ShotSpotter performs real-time spooling of all signals captured at a sensor, to support later detailed forensic and intelligence analysis of events. Such information can include other non-weapons events, weapon type and direction of fire analysis, and even information related to the direction and speed of shooters on the move.

Forensic evidence from a drive-by shooting
11 shots fired by two gunmen in vehicle moving NNW @ 9mph
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