Efficient, electrically small metamaterial-inspired antennas with high directivity

摘要

It has been demonstrated that metamaterial-inspired electrically small antennas (ESAs) can be designed to have high radiation efficiencies and even large bandwidths with non-Foster circuit augmentations. However, being electrically small, it still remains a challenge to obtain directivities over interesting bandwidths which exceed those of simple dipoles, especially with only passive constructs. Different classes of passive and active metamaterial-inspired ESAs that have successfully produced higher directivities and higher bandwidths will be reviewed. Recently reported configurations will be highlighted in our presentation.