The current situation in Iraq is making it extremely clear that the urban environment is a chaotic and dangerous battle space. Currently available technology cannot provide the level of real-time situational awareness needed by each individual soldier. DARPA has determined that Sparse Conformal Acoustic Network (SCAN) technology, or soldier-worn acoustic-array vests, is a potential solution to this problem. The primary goal of this SBIR is to develop and transition a sparse conformal acoustic network system (SCAN) to the US Army, a capability that will provide a revolutionary improvement in hearing for more complete situational awareness in urban operations. Phase I showed that gains of 20-40 dB over the unaided ear are feasible. The goal of this Phase II is to develop a limited-capability prototype SCAN system and demonstrate its capabilities in typical urban environments, which will set the stage for final system development and transition of SCAN in Phase III. This prototype will include sensor-nodes with unique high-gain arrays and special purpose digital boards for real-time, broadband, sparse, conformal array beamforming; user-nodes for special human computer interfacing for enhanced hearing; and the networking of these nodes to exploit the synergy of multiple arrays and users. URBAN WARFARE, MICROPHONE ARRAYS, BROADBAND ARRAYS, SPARSE ARRAYS, CONFORMAL ARRAYS, ULTRASOUND, AIR-ACOUSTICS, ATR