Miniaturisation schemes for metallodielectric electromagnetic bandgap structures

Two miniaturisation schemes for metallodielectric electromagnetic bandgap (MEBG) arrays are presented. Miniaturisation by virtue of the closely coupling technique as well as by employing complex element geometries is demonstrated by means of full-wave simulations and experimental results. A combination of the two techniques is shown to produce a further miniaturisation. An MEBG array with unit cell lambda/35 is experimentally demonstrated. The concepts are expanded for the miniaturisation of artificial magnetic conductor (AMC) surfaces. It is demonstrated that there is a trade-off between AMC miniaturisation and bandwidth. The motivation behind the miniaturisation is demonstrated with a test mobile handset employing a miniaturised conformal MEBG surface. The handset´s antenna efficiency and frequency detuning are improved in the presence of the user´s hand