Accurate Design Procedure for Waffle-Iron Low-Pass Filter

In this paper, an accurate synthesis procedure for designing classical low-pass waffle-iron waveguide filters is proposed. The novel design technique is based on the decomposition of the filter into a finite number of design entities (DEs), which are composed of a waffle -iron section inserted between two uniform rectangular waveguide sections. Then, the physical dimensions of each DE are calculated by means of their associated frequency responses along the device. The proposed method has been tested through the design of a Ku-band filter, which shows a remarkable accordance between the ideal and simulated frequency response. A prototype of this filter has been also fabricated to prove the feasibility of designing classical waffle-iron filters with the novel design procedure.