stamp modeling, analysis and design of defected microstrip structure for lowpass filters based on properties of metamaterials

Defected microstrip structure (DMS) is one kind of metamaterials, which has many characteristics that bandgap and slow wave characteristic and so on. Three types of defected microstrip structure (DMS) units which are cross-shaped, round-head-shaped and square-head-shaped DMS are proposed and investigated. Further, three DMS units are used in the design of lowpass filters (LPFs) and the obtained performances are examined. Based on three DMS units, three lowpass filters using sixteen cascaded proposed DMS units are designed and fabricated. The designed LPFs exhibit sharp cutoff frequency response, low insertion loss, and excellent stopband performance.