Wideband Dipoles on Electromagnetic Bandgap Ground Planes

Research output: Contribution to journalArticle

Authors

Colleges, School and Institutes

Abstract

The performance of broadband dipole antennas above electromagnetic bandgap (EBG) structures is investigated.. Two different structures are examined. One is a diamond dipole over an EBG with square patch elements optimized by hand and the other an open sleeve dipole over an EBG optimized by a genetic algorithm (GA). Both configurations demonstrate that a low profile dipole antenna over an EBG can have a broad bandwidth. Careful design of both is required and in particular for best results, the antenna-EBG system should be optimized together, rather than as separate components. The performance is compared to an absorber backed wideband dipole antenna and it is found that the gain is significantly increased, whilst the bandwidth is reduced. In general, for the diamond dipole antenna return loss bandwidths of over 2:1 (67%) have been achieved, although radiation pattern control is difficult and reduces the bandwidth to the order of 1.4:1 (33%). The sleeve dipole over an EBG achieved a bandwidth of 1.28:1 (26%). The realized gain, which is power gain reduced by input match loss, of both structures are approximately the same. GA optimization and parametric studies seem to suggest that bandwidths significantly greater than these are difficult to achieve.

Details

Original languageEnglish
Pages (from-to)2426-2434
Number of pages9
JournalIEEE Transactions on Antennas and Propagation
Volume55
Issue number9
Publication statusPublished - 1 Sep 2007

Keywords

  • wideband dipole antenna., genetic algorithm (GA), Electromagnetic bandgap (EBG), low profile antenna