A Two-element Parasitic Antenna Approaching the Minimum Q-factor at a Given Directivity
@article{Ferrero2017ATP, title={A Two-element Parasitic Antenna Approaching the Minimum Q-factor at a Given Directivity}, author={Fabien Ferrero and Leonardo Lizzi and Lars Jonsson and Lei Wang}, journal={arXiv: Applied Physics}, year={2017} }
In this paper we investigate a super-directive antenna based on a parasitic structure with a circumscribing sphere of diameter 69 mm corresponding to 0.2$\lambda$@880 MHz. The antenna is modeled, simulated, measured, and it is also evaluated against the new Q-factor bound for small antennas at a given total directivity. A maximum directivity of 7.2 dBi is measured with a radiation efficiency of -6.5 dB at 876 MHz. An intermediate directivity of 6.2 dBi is observed at 880 MHz with 20 dB front-to…
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