Microstrip dual-band bandpass filter design using folded coupled lines

Abstract

A new microstrip dual-band bandpass filter using folded coupled lines is designed and fabricated in this paper. The proposed filter exhibits two center frequencies at 2.6 GHz and 5.48 GHz with the corresponding fractional bandwidth of 23% and 11.8% respectively. The filter demonstrates good performance in terms of low insertion loss and high return loss at the lower and upper passband. The measurement results of the proposed filter, with overall size of 17.2×17.2 mm 2 , are in good agreement with the simulations ones