Compact ultra wide band filter using triangular patch resonators

A compact ultra wide band pass filter has been proposed in this paper. The band pass operation of the filter has been obtained with the combinations of high pass filter and low pass filter. The low pass filter used in the combined structure is designed using the triangular patch resonators and the high pass filter is designed using shorted stubs. The three different topologies to combine the low pass and high pass filter are compared. The final structure gives a very compact configuration of ultra wide band pass filter. The design methodology of the proposed filter is elaborated. The designed structure is simulated and fabricated. The group delay of the filter gives almost flat for the entire operation band. A good agreement has been seen between simulated and measured values of scattering parameters. The fractional band width has been achieved as 130%.