Journal article
Superdirective Magnetic Dipole Array as a First-Order Probe for Spherical Near-Field Antenna Measurements
The theory as well as numerical and experimental results are presented for a superdirective array composed of closely spaced electrically small resonant magnetic dipole elements. The array operates on a metal ground plane and can exhibit a maximum directivity of 11.5 dBi, 15.2 dBi, and 17.8 dBi (including 3 dB due to the ground plane), for 2, 3, and 4 magnetic dipoles, respectively.
The array is self-resonant and is directly excited by a 50-ohm coaxial cable through the ground plane. The array radiates essentially the $\vert\mu\vert=1$ spherical modes, which, despite a narrow bandwidth, makes it an excellent first-order probe for spherical near-field antenna measurements at low frequencies.
Language: | English |
---|---|
Publisher: | IEEE |
Year: | 2012 |
Pages: | 4670-4676 |
ISSN: | 15582221 and 0018926x |
Types: | Journal article |
DOI: | 10.1109/TAP.2012.2207363 |
ORCIDs: | Kim, Oleksiy S. and Breinbjerg, Olav |
Electrically small antennas, First-order probe Magnetic dipole Spherical near-field antenna measurements Superdirectivity Supergain array
Antenna arrays Antenna measurements Arrays Bandwidth Dipole antennas Electrically small antennas Magnetic resonance Probes close space electrically small resonant magnetic dipole elements coaxial cable coaxial cables dipole antenna arrays first-order probe gain 3 dB magnetic dipole magnetic moments narrow bandwidth resistance 50 ohm spherical near-field antenna measurement spherical near-field antenna measurements superdirective magnetic dipole array superdirectivity supergain array