Panel Antenna2011-2012 Capstone Senior Design

Technical Presentation: April 27, 2012

Sponsored by:

Website: seniordesign.engr.uidaho.edu/2011-2012/panelantenna

The TeamAllan Davis: Project Lead

Carlos Gonzalez: Budget/Resource Manager

Cooper McBride: Website Developer

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ObjectiveDesign, fabricate and test a 900-Mhz

directional panel antenna for Schweitzer Engineering Laboratories

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ApplicationsRadios provide comm channels for electric utility

protection, monitoring, and controlEconomical alternative to fiber-optic cableBackup primary protection channelsMany more possible applications of wireless

communications for critical infrastructure

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What SEL NeedsAn antenna that will have performance similar to

antennas that are currently supplied by outside sources

The antenna will be used with the SEL-3031 Serial Radio Transceiver

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Yagi AntennaSEL is currently selling directional Yagi

antennas with the SEL-3031An example of a 5-element Yagi is shown here

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Design ProcessResearch of existing antenna designsComputer simulations using Agilent EMPro

softwareFinite-difference time-domain (FDTD)Finite element method (FEM)

We fabricated several design variations based on our simulation results

We tested the designs with different backplate spacings using SELs RFI chamber

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Final DesignDirectional Bowtie Antenna

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Far-Field Radiation Patterns

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Horizontal Plane

TestedSimulated

Main Lobe

Side Lobes

Main Lobe

Back Lobe

SpecificationsOperating frequency range: 900-930 MHzDirectionalUsed for either vertical or horizontal

polarizationGain ≈ 6 dBi3-dB Beamwidth ≈ 65°Designed using printed circuit board technologyFR-4 substrateBackplate spacing: 83 mm (λ/4)

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Challenges during the projectSoftware

PC compatibility issuesConvergence issuesSimulation times ranged from ½ hour to 7

hoursCorrectly interpreting simulation results

Extensive trial and error to get useable dataLimited availability of RFI chamber

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Recommendations for future workInvestigate using an array of 2-4 bowtie

elements for improved directionalityMatch the input impedance to 50 Ω using a

microstrip matching network (quarter-wave impedance transformer, etc.)

The antenna should be characterized by a professional antenna laboratory before production

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Special ThanksAdvisors:

Dr. Greg DonohoeDr. Touraj Assefi

Sponsors: Eric Sagen Henry Loehner

Dr. Jeff YoungDr. Chris Wagner

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Questions?

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