02078nas a2200181   4500008004100000245005800041210005800099260001300157300001400170520157700184653001401761653000801775653001501783653001201798100002101810700001501831856005001846       2004                        eng d00aExtracting tactical information from acoustic signals0 aExtracting tactical information from acoustic signals  cDecember  a149–1533 aSmart acoustic sensor systems can be deployed for the automatic detection, localization, classification and tracking of military activities, which are inherently noisy. Acoustic sensors are appealing because they are passive, affordable, robust. and compact. Also, the propagation of sound energy is not limited by obstacles, which block or obscure the clear line of sight that is required for the effective operation of electromagnetic systems. Methods, with examples, for extracting tactical information from acoustic signals emitted by moving sources (air and ground vehicles) are provided for both single sensor and multiple sensor configurations. The methods are based on processing either the narrowband or broadband spectral components of the source's acoustic signature. For example, the tactical information extracted by narrowband processing of single sensor data for a moving source is the source speed, slant range and time at the closest point of approach, as well as the source (or rest) frequency of the narrowband signal. For an array of sensors, the tactical information consists of estimates of a complete set of target motion parameters, which indicate the speed and trajectory of the source. Weapon firings generate acoustic impulses and supersonic projectiles generate acoustic shocks, which can be localized and classified using spatially distributed acoustic sensors. The methods developed for land-based acoustic surveillance using microphone data are also applied to hydrophone data for passive acoustic surveillance of the underwater environment.10aacoustics10aasr10amonitoring10asensors1 aFerguson, B., G.1 aLo, K., W.  uhttp://dx.doi.org/10.1109/ISSNIP.2004.141745301394nas a2200217   4500008004100000245011500041210006900156260000900225300001200234490000900246520066600255653001400921653001100935653000800946653001500954100002100969700001400990700002001004700002601024856012601050       2008                        eng d00aMaritime acoustic detection of aircraft to increase flight safety and homeland security: an experimental study0 aMaritime acoustic detection of aircraft to increase flight safet  bSPIE  a69430Z+0 v69433 aFor several years ARL has studied acoustics to track vehicles, helicopters, Unmanned Aerial Vehicles (UAV) and others targets of interest. More recently these same acoustic sensors were placed on a simulated buoy in an attempt to detect and track aircraft over a large body of water. This report will investigate the advantages of using acoustic arrays to track air and water craft from a fixed floating platform as well as potential concerns associated with this technology. Continuous monitoring of aircraft overflight will increase situational awareness while persistent monitoring of commercial and military flight paths increases overall homeland security.10aacoustics10aamibio10aasr10amonitoring1 aSolomon, Latasha1 aSim, Leng1 aTenney, Stephen1 aCarapezza, Edward, M.  uhttp://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=PSISDG00694300000169430Z000001&idtype=cvips&gifs=yes