A compact tunable bandpass filter with high selectivity and low insertion loss using novel CRLH cell

• This paper presents the realization of a tunable bandpass filter with high selectivity and low insertion loss using one tunable composite right/left-handed (CRLH) cell. The tunable CRLH cell is proposed with varactor diodes loaded both on series and shut circuits. Two shut circuits are designed to form the needed paralleled C-R and L-L, by which two transmission zeros beside the passband are obtained at the same time. Each varactor diode is shunted by a lumped capacitor for lower insertion loss. The filter is tuned by only one DC bias, which results in easily control and compact size. The measured results agree well with the simulated results, and a tunable range of the center frequency from 1.75 to 2.25GHz is achieved in measurement with the insertion loss less than 2.5dB.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Elektroteknik och elektronik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Electrical Engineering, Electronic Engineering, Information Engineering (hsv//eng)

Keyword

Handed Transmission-Line

Phase-Shifter

Resonators

Microstrip

Bandwidth

Design

Publication and Content Type

ref (subject category)

art (subject category)