Panel Antenna 2011 2012 Capstone Senior Design Technical

Panel Antenna 2011 -2012 Capstone Senior Design Technical Presentation: April 27, 2012 Sponsored by: Website: seniordesign. engr. uidaho. edu/2011 -2012/panelantenna

The Team �Allan Davis: Project Lead �Carlos Gonzalez: Budget/Resource Manager �Cooper Mc. Bride: Website Developer 2

Objective �Design, fabricate and test a 900 -Mhz directional panel antenna for Schweitzer Engineering Laboratories 3

Applications �Radios provide comm channels for electric utility protection, monitoring, and control �Economical alternative to fiber-optic cable �Backup primary protection channels �Many more possible applications of wireless communications for critical infrastructure 4

What SEL Needs �An 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 5

Yagi Antenna �SEL is currently selling directional Yagi antennas with the SEL-3031 �An example of a 5 -element Yagi is shown here 6

Design Process �Research of existing antenna designs �Computer simulations using Agilent EMPro software �Finite-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 7

Final Design �Directional Bowtie Antenna 8

Far-Field Radiation Patterns Simulated Tested Horizontal Plane Back Lobe Main Lobe Side Lobes Main Lobe 9

Specifications �Operating frequency range: 900 -930 MHz �Directional �Used for either vertical or horizontal polarization �Gain ≈ 6 d. Bi � 3 -d. B Beamwidth ≈ 65° �Designed using printed circuit board technology �FR-4 substrate �Backplate spacing: 83 mm (λ/4) 10

Challenges during the project �Software �PC compatibility issues �Convergence issues �Simulation times ranged from ½ hour to 7 hours �Correctly interpreting simulation results �Extensive trial and error to get useable data �Limited availability of RFI chamber 11

Recommendations for future work �Investigate using an array of 2 -4 bowtie elements for improved directionality �Match 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 12

Special Thanks �Advisors: �Dr. Greg Donohoe �Dr. Touraj Assefi �Sponsors: �Eric Sagen �Henry Loehner �Dr. Jeff Young �Dr. Chris Wagner 13

Questions? 14