Sponsored by

RF Signal Source Mapping using low cost spectrum

analysis

Dan Wells

Supervised by: Barry Irwin and Ingrid Siebörger

Dan Wells // Barry Irwin // Ingrid Siebörger

Outline of presentation

Problem Statement Project outline and goals WiSpy SSM Tool (three parts)

Screenshots in action Conclusions Future work

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Dan Wells // Barry Irwin // Ingrid Siebörger

Problem Statement

802.11a > Not common (and 5 GHz) 802.11b/g > Popular 802.11n > New and improved 802.11b/g/n all use 2.4 GHz range Frequency is becoming cluttered Need to use optimal channel, minimise

interference and discover rogue AP’s and remove

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Dan Wells // Barry Irwin // Ingrid Siebörger

Project Outline and Goals

Using three (minimum) synchronised spectrum analysers can we trilaterate a RF signal in the range (2400-2483MHz) ?

Produce a tool in MS Visual C# to collect frequency VS amplitude data and process it

Display signal data meaningfully Evaluate the tool for accuracy

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Dan Wells // Barry Irwin // Ingrid Siebörger

WiSpy SSM Tool Design and Implementation

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Dan Wells // Barry Irwin // Ingrid Siebörger

WiSpy SSM Collector

Interfaces with the MetaGeek WiSpy through a USB Human Interface Device (HID) API

Collects chunks of signal data Passed directly to webservice Or, stored locally and transmitted later

Passes node name, associated time and location with the signal data

Location -> Updated dynamically via GPSHonours Presentation – November 07

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Dan Wells // Barry Irwin // Ingrid Siebörger

Screenshots of WiSpy SSM Collector [1/2]

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802.11b

802.11g

802.11n

Dan Wells // Barry Irwin // Ingrid Siebörger

Screenshots of WiSpy SSM Collector [2/2]

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Dan Wells // Barry Irwin // Ingrid Siebörger

ASP.NET Webservice

Interface to SQLite Database Request and Response SOAP/XML Stateless MD5 hash checking database initialisation

protection Deployed to Microsoft IIS

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Dan Wells // Barry Irwin // Ingrid Siebörger

WiSpy SSM Compiler

Send requests to the webservice for specific time ranges of data for selected collecting nodes

Signal data is sorted (sync’d to time), displayed, played and replayed to user

All data can be saved to file via XML serialization and reloaded offline

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Dan Wells // Barry Irwin // Ingrid Siebörger

Formula for distance signal is transmitted

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Dan Wells // Barry Irwin // Ingrid Siebörger

WiSpy SSM Compiler

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Dan Wells // Barry Irwin // Ingrid Siebörger

Evaluation Setup

One access point D-Link DWL-2100 802.11b

One wireless desktop client Regular traffic Three collecting nodes (two fixed, one

mobile)

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Dan Wells // Barry Irwin // Ingrid Siebörger

Results [1/4]

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Dan Wells // Barry Irwin // Ingrid Siebörger

Results [2/4]

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Dan Wells // Barry Irwin // Ingrid Siebörger

Results [3/4]

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Dan Wells // Barry Irwin // Ingrid Siebörger

Results [4/4]

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Dan Wells // Barry Irwin // Ingrid Siebörger

Conclusion

Goals achieved Graphically display signal strength at each

node meaningfully Fairly accurate

Tool produced WiSpy SSM Collector (2238 lines) WiSpy SSM Compiler (1590 lines) Webservice (354 lines)

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Dan Wells // Barry Irwin // Ingrid Siebörger

Future Projects

Integrate a spectrum analyser with higher resolution and more functionality (WiSpy 2.4x, Cognio Spectrum Expert?)

Test with more WiSpy devices

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Dan Wells // Barry Irwin // Ingrid Siebörger

Questions?

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