Design and measurements of an electrically small, broad bandwidth, non-Foster circuit-augmented protractor antenna

Abstract

A broad bandwidth, electrically small, metamaterial-inspired protractor antenna was designed, fabricated and tested around 300 MHz. Its broad bandwidth property was achieved by augmenting the protractor-shaped near-field resonant parasitic (NFRP) element with a non-Foster circuit. The resulting active NFRP element provided the means to surpass the fundamental passive limits. The measurement results for this non-Foster protractor antenna showed more than a 10 times increase of the 10 dB fractional bandwidth (FBW 10dB) of the original passive version. The corresponding half-power bandwidth (BW 3dB) was more than 8.24 times the passive upper bound. © 2012 American Institute of Physics