Design, analysis and implementation of novel metamaterial transmission line with dual composite right/left-handed and conventional composite right/ left-handed properties

The design, analysis and implementation of new metamaterial transmission line (TL) are presented. The proposed metamaterial TL exhibits dual composite right/left-handed characteristics at low/middle-frequency bands and conventional composite right/left-handed characteristics at middle/high-frequency bands. Therefore it should be left-handed property at middle-frequency band and right-handed property at low/high-frequency bands to achieve the proposed characteristics. Circuit models that meet the requirements are discussed. The operating principles and characteristics of the representative circuit model are investigated by means of its balanced conditions, typical dispersion/attenuation and Bloch impedance curves. Furthermore, handedness characteristics of the metamaterial TL, including double positive (right handed), double negative (left hed), epsilon-negative and mu-negative bands, are discussed. An implementation of the proposed metamaterial TL is constructed based on microstrip line and defected ground structure technologies.