Multiband antenna using +1, −1, and 0 resonant mode of DGS dual composite right/left handed transmission line

AbstractThe multiband antenna using defected ground structure (DGS) dual composite right/left handed transmission line (D‐CRLH TL) is proposed. The D‐CRLH TL resonator can provide a multiband using positive, zero, and negative modes without the different length resonators because the D‐CRLH TL has inherent three bands in half periodicity. To design and analyze the proposed antenna, the circuit simulation of the two stage DGS D‐CRLH resonator is executed by the equivalent circuit and the results are compared with those of full wave simulation and experiment. The results show that the presented antenna has such a reasonable radiation characteristics of efficiency, bandwidth, and size that it is suitable for compact multiband antenna. In addition, a theoretically unexpected radiation mode, which is generated by the DGS, is observed in the stop band. This additional mode could be utilized for the multi‐band antenna. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2485–2488, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24649