Compact Two-Element Printed Monopole Array With Partially Extended Ground Plane

The compactness of antenna arrays is highly restricted due to the mutual coupling effect between radiation elements, which degrades the arrays' performances with respect to impedance matching, radiation efficiency, and antenna diversity. A two-port compact printed monopole antenna array with a novel and simple decoupling structure based on partially extended ground plane applicable for small terminals is presented. The distance between the printed monopole elements is less than
$0.25\lambda$
. A broad matching and decoupling bandwidth up to 1.5 GHz (5.1–6.6 GHz) is achieved. The approach is proven by both simulations and measurements.