Design of compact printed 2.4 GHz band-pass filter using LC resonator

Abstract

A compact Printed 2.4GHz band-pass filter using inductance-capacitance (LC) resonator is implanted and measured. The proposed filter is designed by using LC resonator to avoid the limitation of the physical wavelength for reducing filter size. For improving filter performances, the quality factors of the lump elements are optimized. The measured results show minimum insertion loss is 0.59 dB in 2.33 GHz, and the ripple in pass-band is less than 1.6 dB in pass-band. The 3dB bandwidth is 1.834 GHz. In addition, the losses in stop-bands are larger than 20dB in the band from 3.75 GHz to 8 GHz. The filter size is small with 19.9×10 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . The proposed filter can be implemented in standard printed circuit board processes without any lumped elements, bonding wires, easing integration with wireless communication systems.