A Reconfigurable Pseudohairpin Filter Based on MEMS Switches

Area of Science:

• Electrical Engineering
• Microwave Engineering
• Filter Design

Background:

• Hairpin-line structures are favored for compact microstrip filters, often without requiring ground connections for resonators.
• Reconfigurable filters are crucial for adapting to dynamic communication standards.
• Radio Frequency Micro-Electro-Mechanical Systems (RF-MEMS) switches offer potential for high-performance tunable RF components.

Purpose of the Study:

• To present a bandpass-reconfigurable planar pseudohairpin filter utilizing RF-MEMS switches.
• To investigate the tunability, quality factor, and overall capability of the RF-MEMS based filter.
• To compare the performance of the RF-MEMS tunable filter against traditional PIN diode-based tunable filters.

Main Methods:

• Designed and fabricated a planar pseudohairpin filter incorporating U-shape resonators for improved interdigit coupling.
• Integrated RF-MEMS switches to modify resonator lengths via added microstrip segments, enabling control over filter parameters.
• Conducted numerical and experimental assessments of the prototype filter's performance characteristics.

Main Results:

• The RF-MEMS tunable filter demonstrated effective control over center frequency, bandwidth, and return loss.
• The prototype exhibited a wide center frequency tuning range and high quality factor.
• Performance metrics were favorably compared against existing tunable filter technologies.

Conclusions:

• The RF-MEMS based tunable hairpin filter offers superior performance in terms of center frequency tuning range, compactness, and power consumption compared to PIN diode switches.
• RF-MEMS technology shows significant potential for next-generation communication standards operating in high microwave frequency bands.
• The developed filter design is a promising solution for advanced, reconfigurable RF systems.