  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-back ratio and -7 dB radiation
efficiency. The antenna performs well with respect to the developed fundamental
bound. The results is promising for applications that require miniaturization
and spatial filtering. The above antenna properties are robust and we show with
measurements that the antenna preform well also when it is integrated as an
autonomous unit.
