Publication Date

Summer 2019

Degree Type


Degree Name

Master of Science (MS)


Electrical Engineering


Lili He


microwave, multilayer, PCB, RF, transmission, via

Subject Areas

Electrical engineering


While allowing for flexible trace routing and device miniaturization, multilayer printed circuit boards (PCB) suffer from performance issues at high frequency due to the impedance mismatch caused by vertical transitions. In this paper, a process for optimizing the high-speed performance of microstrip to stripline transitions in multilayer PCBs is demonstrated. This includes strategic tuning of via dimensions using time-domain reflectometry and an analysis of the use of shielding vias to prevent parasitic cavity resonance. Simulations of optimized 2-layer, 4-layer, and 6-layer microstrip to stripline transitions show a return loss of 20 dB up to 7 GHz. To demonstrate a useful microwave application, a planar filter with a passband of 4 GHz to 6 GHz is submerged 6-layers. The simulation shows that when paired with the optimized vertical transitions, the filter can maintain performance.