There are over a hundred "gunshot detectors" in Iraq, but the troops are not wildly enthusiastic about them. The main criticism is the number of false alarms. The current generation of detectors use acoustic sensors. These devices have come a long way in the last decade, by virtue of major advances in computing power, sensor quality and software development. But there are still a lot of false alarms, and on a battlefield, that can be hard on the nerves. A solution may be at hand. A new detector, using an infrared sensor, detects the object (bullet) itself, and eliminates the false alarms. That's because there aren't too many objects flying around at two or three thousand feet a second that are not bullets (and definitely are dangerous, no matter what they are.) The new detector has passed field tests in the United States, and production units will be soon sent to the troops. These systems, no matter what sensor they use, have gotten a lot more user friendly. They give timely alerts and good information (about where the shooter is) very quickly. The infrared senor, however, also gives very accurate data on the caliber of the projectile, information which can also be useful on the battlefield. Ambush has long been the favorite form of combat, but these gunshot detectors make it more difficult to make an ambush work.