New microstrip filter using single right-angled triangular patch resonator

Currently, miniature microstrip filters with dual-mode operation have been widely studied and reported, however, numerous higher order modes are seldom used for a filter design. Multi-mode technique is regarded as one of the most effective methods for a bandpass filter with wideband and miniaturization implementation. This report presents bandpass filters with higher order mode and multi-mode operation by using single isosceles right-angled triangular patch resonator, and a single patch bandstop filter is also implemented. The new filters are some applications of right-angled triangular patch resonator which is of much less attention, and will be quite useful in modern RF circuits.