A miniature 800–1100-MHz tunable filter with high-Q ceramic coaxial resonators and commercial RF-MEMS tunable digital capacitors

Abstract

This paper presents the design and characterization of a miniaturized tunable bandpass filter utilizing high-Q ceramic coaxial resonators and commercially available RF-MEMS tunable digital capacitors. A proof-of-concept 2-pole tunable filter occupying only 10 × 10 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> is demonstrated with a frequency tuning range of 800-1100 MHz and bandwidth tuning range of 6-13%.