Shooter localization and weapon classification with soldier-wearable networked sensors

The paper presents a wireless sensor network-based mobile countersniper system. A sensor node consists of a helmetmounted microphone array, a COTS MICAz mote for internode communication and a custom sensorboard that implements the acoustic detection and Time of Arrival (ToA) estimation algorithms on an FPGA. A 3-axis compass provides self orientation and Bluetooth is used for communication with the soldier’s PDA running the data fusion and the user interface. The heterogeneous sensor fusion algorithm can work with data from a single sensor or it can fuse ToA or Angle of Arrival (AoA) observations of muzzle blasts and ballistic shockwaves from multiple sensors. The system estimates the trajectory, the range, the caliber and the weapon type. The paper presents the system design and the results from an independent evaluation at the US Army Aberdeen Test Center. The system performance is characterized by 1-degree trajectory precision and over 95 % caliber estimation accuracy for all shots, and close to 100 % weapon estimation accuracy for 4 out of 6 guns tested

Multi-Modal Target Tracking Using Heterogeneous Sensor Networks

Abstract—The paper describes a target tracking system run-ning on a Heterogeneous Sensor Network (HSN) and presents results gathered from a realistic deployment. The system fuses audio direction of arrival data from mote class devices and object detection measurements from embedded PCs equipped with cameras. The acoustic sensor nodes perform beamforming and measure the energy as a function of the angle. The camera nodes detect moving objects and estimate their angle. The sensor detections are sent to a centralized sensor fusion node via a combination of two wireless networks. The novelty of our system is the unique combination of target tracking methods customized for the application at hand and their implementation on an actual HSN platform. I

MODEL CONSTRUCTION FOR MODEL-INTERGRATED COMPUTING

Complex computer-based systems are characterized by the tight integration of information processing and the physical environment of the systems. Model-Integrated Computing (MIC) is well suited for the rapid design and implementation of such systems. MIC employs domain-specific models to represent the software, its environment, and their relationship. With Model-Integrated Progra

Node-density independent localization

This paper presents an enhanced version of a novel radio interferometric positioning technique for node localization in wireless sensor networks that provides both high accuracy and long range simultaneously. The ranging method utilizes two transmitters emitting radio signals at almost the same frequencies. The relative location is estimated by measuring the relative phase offset of the generated interference signal at two receivers. Here, we analyze how the selection of carrier frequencies affects the precision and maximum range. Furthermore, we describe how the interplay of RF multipath and ground reflections degrades the ranging accuracy. To address these problems, we introduce a technique that continuously refines the range estimates as it converges to the localization solution. Finally, we present the results of a field experiment where our prototype achieved 4 cm average localization accuracy for a quasi-random deployment of 16 COTS motes covering the area of two football fields. The maximum range measured was 170 m, four times the observed communication range. Consequently, node deployment density is no longer constrained by the localization technique, but rather by the communication range

Multigranular Simulation of Heterogeneous Embedded Systems

Heterogeneous embedded systems, where configurable or application specific hardware devices (FPGAs and ASICs) are used alongside traditional processors, are becoming more and more widely used. To facilitate rapid design and development of such heterogeneous hardware/software systems, it is essential to expand the software design cycle to integrate hardware modeling and simulation. Cosimulation and exploration of the joint design space are key problems. To design, develop and verify such systems, different kinds of simulations at various levels of granularity are required. The hardware modeling and simulation framework of the Model-Based Integrated Simulation Framework (MILAN) integrates these requirements into a single powerful design, development and simulation environment. Categories and Subject Descriptors E.3 [HW/SW co-design]: specification, modeling, cosimulation and performance analysis, system leve