Domestic Nuclear Detection Office (DNDO)

Networking Radiation Sensor Systems

NITRD Workshop

September 20, 2012

Richard Vojtech, Ph.D.Principal Deputy Assistant DirectorTransformational and Applied Research Directorate Domestic Nuclear Detection Office

The Questions

1. Will a networked system of portable radiation detectors outperform the same number of individual detector operating independently?

2. Will the networked system improve the ability to:

detect anomalous radioactive materials?

locate the materials?

identify the materials?

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The Program Goal

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To demonstrate advanced technologies that improve the ability to detect, localize, and identify radiological sources by combining data from multiple radiation detector nodes.

Key Questions:

• How does the performance of the ensemble compare to that of the

individual detectors?

• What are the strengths and weaknesses of each system approach?

• Do trends in the data suggest which types of scenarios will

benefit the most from a tightly coupled network?

“Intelligent” Radiation Sensor System

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Advanced algorithms combine the radiation, spatial, and temporal information from multiple sensors to make a collective assessment about the presence and location of radiological sources

N2

N1

N3

N4

N5WirelessComms

Sensor Array

Data Fusion Algorithms

mt

mt+1

mt+2

Data Packet

~1 Hz

• Energy Spectrum • Sensor Position/Orientation• Timestamp

Detector Devices

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General Electric

Passport Systems

Smiths Detection

System Characterization

Subsetting

2 rings6 quadrilaterals

7 triangles

Subsets

2 rings6 quadrilaterals

7 triangles

Detector Pattern: Spiral + Rings

Movable Track

2”x2” NaI (18)

Alt DD (4)

command trailers

background step area

open “field” area

Initial Impressions from a Networked System

In simple cases IRSS shows benefits of networking for detection and agrees well with theoretical expectations

Networking can provide reduction in false alarms at the system level compared to a collection of individual sensors

Tracking of moving sources (even with a single sensor) was achieved with non-directional sensors

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