Figure 9
From: Planar array with bidirectional elements for tunnel environments
Relations between the distance Dy and element coupling. (a) Schematic of the array with two elements arranged along the y direction. (b) S21 versus different distance Dy when the antennas have no decoupling cavities. (c) S21 versus different distance Dy when the antennas have decoupling cavities. The mutual coupling decreases with the distance Dy in both two cases, and S21 map in (c) is approximately 5 dB weaker than that in (b), which means the decoupling cavity can weaken the mutual coupling.
