April 21, 2023 ECE4007 L01, 02, & 03 Fall 2008 1

Detection of Aircraft Using

Passive RadarAli Athar

Luis CardonaThomas KingVarun PrasadRahul Sanon

Blake StewartMisam Taherbhai

Sections: L01, L02, & L03

Georgia Institute of TechnologySchool of Electrical & Computer Engineering

Project Advisor: Prof. Aaron Lanterman

April 21, 2023 ECE4007 L01, 02, & 03 Fall 2008 2

Overview• Covert detection of airborne

objects • System advantages

– System is concealed – No transmitter required – No frequency allocation– Low power requirements

• System Users– Air Traffic Controllers– Military

• Total system cost: $96,932

Airplane

Transmitter

Receiver

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Design Objectives

• Detecting airplane at range of 15-20 miles• Capturing reflected FM radio signals that

have bounced off the airplane• Data processing

– Filtering desired frequencies– Amplifying as well as digitizing them– Computing the signals with software

• Laying the foundation for further analysis

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RF Front End

Figure taken from: A. Lanterman, “DURIP: Integrated Sensing and Computation for Passive Covert Radar, Signals Intelligence, and Other Applications Driven by Moore’s Law”

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Atlanta Area Transmitters

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99.7MHz FM (100kW)

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Periodic Antennas KMA4113

Log Periodic Antenna Antenna positioning

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D103J Discone Antenna

Discone Antenna Frequency (Hz)

Spectrum Analysis

Am

plit

ude

(d

B)

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Antenna SpecificationsD130J Discone

• Diamond Antennas• Omnidirectional• Unity gain of 2dbi• Exploration of

beamforming techniques same as Lockheed Martin’s Silent Sentry 3 system

KMA 4113• Allow exploration of

systems such as Paul Howlands demo system at NATO and Prof. Sahr’s (UW) Manastash Ridge radar

• One pointed to get reflected path signal

• One copies the signal from exploited transmitter

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Frequency Ranges

Antennas

Split

TV50 – 950

MHz

FM88 – 108

MHz

UHF300 – 3K

MHz

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Gain Control Stage

• Maximize number of bits for A/D• Use 8-bit programmable attenuators

Attenuation range: 0 – 16.5 dB

(0.1+0.2+0.4+0.8+1+2+4+8 = 16.5)

SMA

Logic Adapter for TTL signals from I/O board

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Power Source

• Acopian power supply for 15V• 12 Volt power supply for 12V

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Equipment to be Powered

• Preamplifiers require 15V• Oscillators require 12V• Attenuators require 12V

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Project Demonstration

• Acquiring and analyzing data– Antennas– Filters– Attenuators and Amplifiers– Spectrum Analyzer

• Ability to control equipment• Presence of strong carrier and

Doppler shifted tracks in data• Cross correlation with Doppler data

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Current Status & Issues• Antennas

– Two 12ft log-periodic constructed– One discone antenna assembled– Mounting logistics to be figured out

• Filters and Gain control– Map I/O channels with TTL pins– Determine the optimal filter configuration– Organize equipment for interchangeability

• Lack of reliable drivers for A/D conversion

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Completed Design AspectsLegend

Completed

Data Acquisition

Post Data Acquisition

Figure taken from: A. Lanterman, “DURIP: Integrated Sensing and Computation for Passive Covert Radar, Signals Intelligence, and Other Applications Driven by Moore’s Law”

April 21, 2023 ECE4007 L01, 02, & 03 Fall 2008 17

Project Schedule

• Assembled discone antenna Oct 01 • Assembled Log-periodic Antennas Oct 18 • Mapped channel lines to TTL input Oct 21

• Connect log-periodic with filter and amps Nov 01• Operation of one attenuator Nov 08• Mount antennas and pass cable Nov 10• Reading data acquired by cards Dec 08• Reliably detect aircraft Dec 12

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Budget and Cost Analysis

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Summary

• Status– Antennas– Power– Attenuation and A/D conversion– Software scripts

• Great platform– Flexibility– Research usage

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Questions?