Departmental Papers (ESE)


The potential use of metamaterial planar bilayers for synthesizing compact subwavelength leaky-wave radiators in the microwave regime is analyzed in detail. In particular, the possibility of pairing "complementary" metamaterials in order to reduce the dimensions of microwave components is explored for the leaky-wave operation of an open waveguide consisting of a grounded pair of planar layers. In connection with our similar findings in other setups employing such complementary pairings, here we show how the compact resonance at the interface between "negative" and "positive" materials may also be properly exploited in this context. Choosing materials with low constitutive parameters, moreover, shows to be effective for enhancing the directivity of these components. We explore in detail the notable guidance and radiation properties of the anomalous natural modes supported by these bilayered structures, giving some physical insights into the anomalous phenomenon and considering the possible limitations in some realistic setups.

Document Type

Journal Article

Date of this Version

March 2007


Copyright 2007 IEEE. Reprinted from IEEE Transactions on Antennas and Propagation, Volume 55, Issue 3, March 2007, pages 881-891.

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leaky wave antennas, leaky waves, metamaterials, subwavelength structures



Date Posted: 24 April 2007

This document has been peer reviewed.