Graduation Year


Document Type




Degree Name

MS in Electrical Engineering (M.S.E.E.)

Degree Granting Department

Electrical Engineering

Major Professor

Thomas Weller, Ph.D.

Committee Member

Lawrence Dunleavy, Ph.D.

Committee Member

Jing Wang, Ph.D.


3D Printing, Ku-band, Coupler, Power Amplifier, Connector


The design and study of multiple RF direct digital manufactured (DDM) devices are presented in this work. A 2.45 GHz, 180°; hybrid coupler is designed to provide the space required for other system components. The coupler is designed and manufactured on a 32 mil Rogers 4003C substrate and adapted to a 100% in-fill acrylonitrile butadiene styrene (ABS) substrate. A size reduction of 66% is accomplished with a bandwidth of 16%. A DDM Ku band connector is modeled and fabricated using varying relative dielectric constants of 50% and 100% in-fill ABS. The connector maintains less than 0.45 dB of insertion loss up to 14 GHz and greater than 10dB of return loss up to 15 GHz. A lumped component model is also developed to model the damaged transition of the connector with agreement to numerical electromagnetic simulation software. Lastly, a thermal and RF study of a Ku band power amplifier (PA) is performed. Two 5 mil 100% in-fill ABS PA test fixtures are fabricated with a varying number of vias. The designs are biased at various operating points to collect thermal and RF data. The PA operates at 151°C before melting the ABS substrate. A thermal model is developed from the measurement data to predict the temperatures at given power levels with good agreement between simulation and model data.

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