Modelling, design and fabrication of a novel reconfigurable ultra‐wide‐band impedance matching based on RF MEMS technology

Abstract

This study proposes an adaptive impedance-matching network with tremendously reduced dimensions and presents its fabrication process. The proposed radio-frequency micro-electromechanical system (RF MEMS) device is based on a coplanar waveguide design and relies on suspended bridges for impedance tuning. The tuning is controlled by a variable applied DC voltage to the bridges. Preliminary tests validate the device's operation mechanism, and simulations were performed on both the mechanical aspects of the device (bridge gap manipulation) and tuning capabilities. This device presents the possibility of operating in a wide band of frequencies, namely [1-6] GHz, and for load impedances in the interval of [30-90] Ω for the real part and [−10-30] for the imaginary part. The device's resonant frequency and its bandwidth can be modified easily by changing the bridge gap in the RF MEMS.

Optimum power transfer in RF front end systems using adaptive impedance matching technique

“… Refs. Methodology Impedance Type Structure Implementation Bandwidth Convergence time Notes 2 Numerical Insertion loss Flexible Combination Narrow 0.15 s Complex control system, automated tuning, simple analogue components, complex mathematical modeling 4 Analytical Single Flexible Combination Wide 4.25 s alleviated method, linear control components, simple analogue components, automated tuning 15 Numerical Single Fixed Passive Narrow NR Complex mathematical modeling, alleviated method, complex control system 16 Numerical Single Fixed Passive Narrow 4 s Transformers used, complex control system, expensive transformers, nonlinear control components 17 Analytical Insertion loss Fixed Combination Narrow NR Complex control system, nonlinear control components, transformers used 18 Analytical Insertion loss Fixed Passive NR <...>…”

“…Here the voltage controlled variable capacitors are employed in a π-type matching circuit. The matching is implemented for different gap spacing between the transmitter and receiver coils at a fixed frequency; and (iv) using RF MEMS based on a coplanar waveguide based on suspended bridges for impedance tuning 18 . The tuning is controlled by a variable applied DC voltage to the bridges over 1–6 GHz.…”