Transcript Power Amplifier Design and Testing

RF Power Amplifier
Design and Testing
By: Jonathan Lipski and Brandon
Larison
Advisor: Dr. Shastry
Why is this important?
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“Wherever there are wireless
communications, there are
transmitters, and wherever there are
transmitters, there are RF power
amplifiers” -Steve Cripps
Presentation Overview
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Project Goals
Power Amplifier Overview
Branch-Line Coupler
ADS Models
Simulation Results
Final Results
Concluding Remarks
Questions
Project Goals
• Building of Power Amplifier Module
using:
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Commercially Available Power Amplifier Chip
Power Splitter/Combiner designed from
scratch
• WiFi application (2.4-2.5 GHz)
• Output Power = 100mW
RFMD RF5622 Power Amplifier
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Input/Output Matching
DC Bias Circuits
RF5622 Power Amplifier Layout
Power Amplifier Module
Power Splitters/Combiners
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Why use them?
• Same gain
• Higher power
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Branch Line vs. Wilkinson
• Extra Resistor Needed
Branch Line Coupler Model
Branch Line Coupler Theory
Calculations
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Widths & Lengths
• MSTRIP.exe
• Center Frequency and Characteristic
Impedance
• VT-42 Data Sheet (Micro Circuits)
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Height of substrate
Dielectric Constant
First Iteration ADS Model: BLC
First Iteration ADS Results: BLC
Port Performance relative to Port 1
Return Losses
Phase Difference
Isolation Losses
Tuned ADS Model: BLC
Tuned ADS Model Results: BLC
Port Performance relative to Port 1
Return Losses
Phase Difference
Isolation Losses
ADS Layout: BLC
First Iteration ADS Model:
PA Module
First Iteration ADS Results:
PA Module
Port Performance relative to Port 1
Return Losses
Phase Difference
Isolation Losses
Tuned ADS Model: PA Module
Tuned ADS Results: PA Module
Port Performance relative to Port 1
Return Losses
Phase Difference
Isolation Losses
ADS Layout: PA Module
ADS Layout: PA Chip
PA Module
Testing Procedure
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WiMAX
• Instrumentation cannot handle the
power levels we’ll be using
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WiFi
• Requires much less power
Testing Procedure
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Network Analyzer
• Measures Return Losses, VSWR,
S-Parameters
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Spectrum Analyzer
• Measures Output Power
Final Results
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Board currently needs to be soldered
Testing will occur after
Results and Simulation comparisons
will be documented in final report
Concluding Remarks
Aspects we learned:
• Power Amplifier Theory
• Power Divider/Combiner Design
• Microstrip Line Fabrication
Concluding Remarks
Recommendations for Future:
• Choose the design first, application
second
• Estimate fabrication time, then double it
References
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Cripps, Steve C. RF Power Amplifiers for Wireless Communications.
Boston: Artech House, 1999. Print.
Gonzalez, Guillermo. "4.7-4.8." Microwave Transistor Amplifiers:
Analysis and Design. Upper Saddle River, NJ: Prentice Hall, 1997.
352-74. Print.
Grebennikov, Andrei. "Power Amplifier Design Fundamentals: More
Notes from the Pages of History." High Frequency Electronics May
2010: 18-30.
"High Power RF Amplifier." RF Power Amplifier | Powerful
Amplification. Web. 25 Sept. 2011.
<http://www.rfpoweramplifier.org/high_power_rf_amplifier.html>.
"RF Power Amplifier." Wikipedia, the Free Encyclopedia. Web. 25
Sept. 2011. <http://en.wikipedia.org/wiki/RF_power_amplifier>.
RFMD, comp. RF5622 Data Sheet. Greensboro, NC: RFMD, 2006.
Print.
Questions?