“…Usually, the feeding system is made in microstrip technology [4], and is placed below the ground, possibly in a metal cavity, in order to suppress electromagnetic coupling with other microwave devices. Such a structure can be rigorously analysed with the use of the IE-MoM approach, as it was already demonstrated by the authors, for example, in [5] and [6]. In such a case, the IE-MoM approach involves modelling both the DRA and the feeding system embedded inside the cavity.…”