The design of waveguide filters based on cross-coupled resonators

This article addresses the physical realization of crosscoupled waveguide filters based on electromagnetic (EM) simulations. For this design procedure, the filter structure is simulated by successively adding one resonator at a time. The desired filter response is achieved without the need of a global optimisation on all the mechanical dimensions within an EM simulator. This reduces the design time required for a crosscoupled waveguide filter and allows the possibility of building high-order waveguide filters with complex crosscouplings. A sixth order X-band dual-band filter with a center frequency of 10 GHz and a fractional bandwidth of 1% is designed using this procedure and presented here as an example. Excellent agreement between simulation results and theoretical results from coupling matrix verifies the proposed approach. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:3–8, 2014