Design and Analysis of Planar Transmission Lines and Semiconductor Components for RF Switching Applications
Ortega, Lucas (2025)
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:amk-2025052817757
https://urn.fi/URN:NBN:fi:amk-2025052817757
Tiivistelmä
This thesis explores the characteristics of planar transmission (CPW) and semiconductor components. The objective is to evaluate their suitability for constructing a solid-state matrix switch aimed at high-throughput characterization of network elements using a two-port Vector Network Analyzer (VNA).
The operational bandwidth was specifically chosen to ensure that the transmission lines could be fabricated and verified using the available equipment in the electronics laboratory at Metropolia University of Applied Sciences. The simulated results were cross-checked with measurements from the fabricated PCBs to validate the accuracy and effectiveness of the design.
The experimental results confirm the feasibility of a 50-ohm semiconductor switch using P-HEMT GaAs FETs for microwave applications, due to their favorable high-frequency characteristics. However, optimal performance relies on proper impedance matching to minimize signal reflections. Discrepancies between simulated and measured data are attributed to uncertainties in the dielectric constant of the FR4 substrate, mechanical tolerances from PCB milling, and variability from manual soldering. These factors can cause impedance mismatches, increased insertion loss, and coupling effects. To improve performance, future designs should consider high-frequency substrates like Rogers RT/duroid 6002 and adopt assembly methods such as reflow soldering, which enhance consistency and reduce parasitics
The operational bandwidth was specifically chosen to ensure that the transmission lines could be fabricated and verified using the available equipment in the electronics laboratory at Metropolia University of Applied Sciences. The simulated results were cross-checked with measurements from the fabricated PCBs to validate the accuracy and effectiveness of the design.
The experimental results confirm the feasibility of a 50-ohm semiconductor switch using P-HEMT GaAs FETs for microwave applications, due to their favorable high-frequency characteristics. However, optimal performance relies on proper impedance matching to minimize signal reflections. Discrepancies between simulated and measured data are attributed to uncertainties in the dielectric constant of the FR4 substrate, mechanical tolerances from PCB milling, and variability from manual soldering. These factors can cause impedance mismatches, increased insertion loss, and coupling effects. To improve performance, future designs should consider high-frequency substrates like Rogers RT/duroid 6002 and adopt assembly methods such as reflow soldering, which enhance consistency and reduce parasitics