Compact UWB BPF with a Tunable Notched Band based on Triplemode HMSIW Resonator

Abstract

A novel triple-mode resonator based on the half-mode substrate integrated waveguide (HMSIW) structure is proposed to design the ultra-wideband (UWB) filters. The UWB filter topology is given by analyzing the resonant frequencies of the three modes and the signs of the coupling between the three modes and the input/output ports. With the filter synthesis method, a triple-mode UWB filter with passband from 3.1-10.6 GHz is effectively realized with two transmission zeros at the upper stopband. To block the existing undesired narrowband radio signals in FCC UWB range, a notched band can be easily generated and controlled by a loaded stub-capacitor. For demonstration, an UWB filter with a tunable notched band from 3.7 to 7.7 GHz and compact size is designed and fabricated. Both simulated and measured results indicate that the proposed new filter has the properties of wide tuning range of the notched band and sharp roll off.Index Terms: Filter; Half-mode substrate integrated waveguide (HMSIW); Tunable notch; Ultra-wideband (UWB).

A New MATLAB based Microstrip Filter Design Tool

“…where =120 Ω is the wave impedance in free space. The effects of strip thickness t are assumed negligible in (1) and (2). This is quite justified in view of the fact that it is generally very small compared to h. However, in case it is large enough, modified versions of (1) and (2) are available in literature [7].…”

“…The use of 'distributed' components becomes an attractive option. Inductors and capacitors are realized using sections of transmission lines in novel ways [1]- [17]. Microstrip line fits well in this category, since it is an easy-to-use transmission line, which can lead to highly compact, cost-effective designs.…”

“…The analysis and synthesis of microstrip filters is a constantly evolving area of research [1]- [17]. Traditionally, such filters were designed using extensive electromagnetic-theory based analyses.…”