FAULT TOLERANT TECHNIQUES FOR WIRELESS AD HOC SENSOR NETWORKS RAM MOHAN BOPPUDI EE 585 :CASE STUDY 2 ram mohan university of kentucky

WIRELESS AD HOC SENSOR NETWORK ram mohan university of kentucky

university of kentucky INTRODUCTION A wireless ad hoc sensor network. Some examples of wireless ad hoc sensor networks are the following: Military sensor networks .   Sensor networks to detect and characterize Chemical, Biological, Radiological, Nuclear, and Explosive (CBRNE) attacks and material.   Sensor networks to detect and monitor environmental changes.   Wireless traffic sensor networks.   Wireless surveillance sensor networks.   Wireless parking lot sensor networks. ram mohan university of kentucky

university of kentucky INTRODUCTION(CONT..) Wireless ad hoc sensor network requirements include the following: Large number of (mostly stationary) sensors.   Low energy use.   Network self-organization.   Collaborative signal processing.   Querying ability. ram mohan university of kentucky

university of kentucky GOALS The basic goals of a wireless ad hoc sensor network generally depend upon the application, but the following tasks are common to many networks: Determine the value of some parameter at a given location.   Detect the occurrence of events of interest and estimate parameters of the detected event or events .   Classify a detected object .   Track an object. ram mohan university of kentucky

university of kentucky SENSOR We focus our attention on how to back-up one type of sensor with another. There are two main reasons for this decision. The first is that technology trends indicate that sensing has by far the highest fault rates. The second is that there is a wide consensus that multi-modal sensor fusion is the key for successful and widespread use of embedded sensor networks. Two fault models: -sensors that produce binary outputs. -sensors with multilevel digital outputs. ram mohan university of kentucky

university of kentucky SENSOR NODE ram mohan university of kentucky

MULTIMODAL SENSOR FUSION Problem of multi modal sensor fusion for digital binary sensors. Sensor resource allocation and assignment problems ask to identify the minimal number of sensors. ram mohan university of kentucky

MULTI MODAL SENSOR NETWORK ram mohan university of kentucky

FAULT TOLERANT SOLUTION ram mohan university of kentucky

TRADITIONAL VS HETEROGENEOUS Traditional methods – double redundancy. - triple redundancy. Importance of heterogeneous over traditional. -low energy. -cost. ram mohan university of kentucky

university of kentucky EXPERIMENTAL RESULTS ram mohan university of kentucky

ALGORITHMIC ENGINES TO SRA PROBLEM Two different techniques to solve the allocation problem: ILP-based and Simulated annealing based. -move. -objective function. -cooling schedule. -stop ping criteria. ram mohan university of kentucky

FAULT TOLERANCE IN MULTIMODAL SENSORY SYSTEMS A number of sensors, some of them different with modalities. The goal is to extract as accurately as possible the information requested by a user from noisy measurements. Four types of sensors in following example for introduced approach. ram mohan university of kentucky

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MULTI MODAL SENSOR SYSTEMS ram mohan university of kentucky

FAULT TOLERANCE IN MULTIMODAL SENSOR SYSTEMS ram mohan university of kentucky

MULTIMODAL SENSOR SYSTEMS ram mohan university of kentucky

university of kentucky CONCLUSION New approach to multimodal sensor fusion. Key idea is to use one type of sensor to back up sensors of different types by exploiting flexibility during multimodal sensor data fusion. Formulated the problem for 2 diff. type of sensors binary and multi-level sensors. Developed algorithms to solve them . ram mohan university of kentucky

university of kentucky REFERENCES Fault tolerance techniques for wireless ad hoc sensor networks by Farinaz Kounshafar Miodrag Potkonjak Alberto Vincentilli. http://w3.antd.nist.gov/wahn_ssn.shtml. ram mohan university of kentucky