Non-foster augmentations of electrically small antennas: Practical design considerations and results

Electrically small antennas (ESAs) have been a topic of much research interest in recent years because of their utility for a wide variety of wireless applications. They have been showcased at several of the iWAT events over the last decade. However, because of their compact size, ESAs are generally not efficient radiators, they have narrow bandwidths, and they have low directivities. I will review my group´s contemporary efforts to overcome the conflicting performance characteristics of ESAs, including their efficiencies, bandwidths, and directivities, using various meta-structures.