Suspended substrate stripline cross-coupled trisection filters with asymmetrical frequency characteristics

Novel compact suspended substrate stripline filters in the Ku band are proposed. Two bandpass trisection filters with asymmetrical characteristics are presented. The use of meandered-line open-loop resonators allows a significant size reduction and either positive or negative cross coupling can be realized. The synthesis is based on the general folded cross-coupled network with parallel resonators and admittance inverters. The suspended substrate technology provides an excellent electrical performance and yields a high quality factor, thus making these filters very attractive for satellite communications systems.