RF Power Amplifier Design and Testing By: Jonathan Lipski and Brandon Larison Advisor: Dr. Shastry

Why is this important? “Wherever there are wireless communications, there are transmitters, and wherever there are transmitters, there are RF power amplifiers” -Steve Cripps “Wherever there are wireless communications, there are transmitters, and wherever there are transmitters, there are RF power amplifiers” -Steve Cripps

Presentation Overview Project Goals Project Goals Power Amplifier Overview Power Amplifier Overview Branch-Line Coupler Branch-Line Coupler ADS Models ADS Models Simulation Results Simulation Results Final Results Final Results Concluding Remarks Concluding Remarks Questions Questions

Project Goals Building of Power Amplifier Module using:Building of Power Amplifier Module using: Commercially Available Power Amplifier Chip Commercially Available Power Amplifier Chip Power Splitter/Combiner designed from scratch Power Splitter/Combiner designed from scratch WiFi application ( GHz)WiFi application ( GHz) Output Power = 100mWOutput Power = 100mW

RFMD RF5622 Power Amplifier Input/Output Matching Input/Output Matching DC Bias Circuits DC Bias Circuits

RF5622 Power Amplifier Layout

Power Amplifier Module

Power Splitters/Combiners Why use them? Why use them? Same gainSame gain Higher powerHigher power Branch Line vs. Wilkinson Branch Line vs. Wilkinson Extra Resistor NeededExtra Resistor Needed

Branch Line Coupler Model

Branch Line Coupler Theory

Calculations Widths & Lengths Widths & Lengths MSTRIP.exeMSTRIP.exe Center Frequency and Characteristic ImpedanceCenter Frequency and Characteristic Impedance VT-42 Data Sheet (Micro Circuits)VT-42 Data Sheet (Micro Circuits) Height of substrate Height of substrate Dielectric Constant 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 WiMAX WiMAX Instrumentation cannot handle the power levels we’ll be usingInstrumentation cannot handle the power levels we’ll be using WiFi WiFi Requires much less powerRequires much less power

Testing Procedure Network Analyzer Network Analyzer Measures Return Losses, VSWR,Measures Return Losses, VSWR,S-Parameters Spectrum Analyzer Spectrum Analyzer Measures Output PowerMeasures Output Power

Final Results Board currently needs to be soldered Board currently needs to be soldered Testing will occur after Testing will occur after Results and Simulation comparisons will be documented in final report Results and Simulation comparisons will be documented in final report

Concluding Remarks Aspects we learned: Power Amplifier TheoryPower Amplifier Theory Power Divider/Combiner DesignPower Divider/Combiner Design Microstrip Line FabricationMicrostrip Line Fabrication

Concluding Remarks Recommendations for Future: Choose the design first, application secondChoose the design first, application second Estimate fabrication time, then double itEstimate fabrication time, then double it

References Cripps, Steve C. RF Power Amplifiers for Wireless Communications. Boston: Artech House, Print. Cripps, Steve C. RF Power Amplifiers for Wireless Communications. Boston: Artech House, Print. Gonzalez, Guillermo. " " Microwave Transistor Amplifiers: Analysis and Design. Upper Saddle River, NJ: Prentice Hall, Print. Gonzalez, Guillermo. " " Microwave Transistor Amplifiers: Analysis and Design. Upper Saddle River, NJ: Prentice Hall, Print. Grebennikov, Andrei. "Power Amplifier Design Fundamentals: More Notes from the Pages of History." High Frequency Electronics May 2010: Grebennikov, Andrei. "Power Amplifier Design Fundamentals: More Notes from the Pages of History." High Frequency Electronics May 2010: "High Power RF Amplifier." RF Power Amplifier | Powerful Amplification. Web. 25 Sept "High Power RF Amplifier." RF Power Amplifier | Powerful Amplification. Web. 25 Sept "RF Power Amplifier." Wikipedia, the Free Encyclopedia. Web. 25 Sept "RF Power Amplifier." Wikipedia, the Free Encyclopedia. Web. 25 Sept RFMD, comp. RF5622 Data Sheet. Greensboro, NC: RFMD, Print. RFMD, comp. RF5622 Data Sheet. Greensboro, NC: RFMD, Print.

Questions?