TITLE:
Development of Compact Ultra-Wideband (UWB) Microstrip Bandpass Filter
AUTHORS:
Kaliyavarathan Thirumalaivasan, Rangaswamy Nakkeeran
KEYWORDS:
Ultra-Wideband, Microstrip, Bandpass Filter, Multiple Mode Resonator, Group Delay
JOURNAL NAME:
Journal of Electromagnetic Analysis and Applications,
Vol.3 No.8,
August
2,
2011
ABSTRACT: Miniaturized Ultra-Wideband (UWB) microstrip bandpass filter with wide passband is presented. The filter is developed based on modified multiple mode resonator, which is formed by transversely attaching three pairs of non-uniform and folded stubs with lowpass and highpass sections. Both sides of high-impedance section are linked with two feed lines via direct coupled lines, resulting UWB bandpass filter. The designed filter provides 7 GHz passband between 2.5 and 9.5 GHz with approximately, –0.5 dB insertion loss, –35 dB minimum return loss at 6.85 GHz, linear phase over the passband and 110% of fractional bandwidth at –3 dB. The computed group delay variation in the passband for the filter is 0.02 ns. The overall dimension of the filter is 10.7 mm (length) × 3 mm (width) × 1.6 mm (thickness).