A RF tunable impedance matching network with a complete design and measurement methodology

This paper presents the design, fabrication, and measurement of a compact narrow band impedance matching network with hybrid technology: coplanar waveguide transmission lines and surface mounted components. The device is a Pi-structure with tunable components made of varactors in series with inductors. Simulations and measurements are in good agreement. Results are arrived at by two measurement methods. They show that complex impedances with magnitudes varying from 6Omega to 1 kOmega can be matched at 1 GHz, with a 50% bandwidth.