A 2-Stage Dual Plane Comb-Line Filter.

This paper presents a new 2-stage dual plane comb-line filter. It is shown by experiment as well as by numerical simulations with FD-TD method that this filter has a wide pass-band and attenuation poles just below and above the pass-band. It is also shown that the characteristics of attenuation poles can be explained by considering the 2-stage filter as a series connection of two 1-stage filters and that the attenuation characteristics of the 2-stage filter can be improved by a simple combination of two 1-stage filters adjusted appropriately.