Antenna Mutual-Coupling Mitigation With Analogue Compensation Network

This work presents a systematic approach supported by theory, simulation, and measurements that demonstrates antenna mutual-coupling reduction by means of an analogue compensation network. This compensation network is realized with two couplers and a passive network based on a 2
^nd
-order band-pass filter. A 3.5 GHz two-element patch antenna is built and used for comparison with the same antenna and compensation network. After a theoretical analysis highlighting the relevant design constraints, simulated and measured results demonstrate a reduction in the antenna
$\vert S_{A12}\vert$
from − 27 dBs to −50 dBs, corresponding to an improvement up to 23 dB over the whole antenna −10dB bandwidth, while the antenna
$S_{A11}$
and
$S_{A22}$
remain unchanged. This
$\vert S_{A12}\vert$
improvement is also shown to improve the far-field radiation pattern for the considered antenna array.