A configuration to double the gain of pyramidal horn antenna using single layer frequency selective surface

A gain enhancement technique in pyramidal horn antenna using a slot type band pass frequency selective surface (FSS) is presented. The horn antenna without FSS has achieved a measured gain of 10.5 dBi at 10 GHz, while the antenna with the single layer slotted FSS yields an enhanced measured gain of 14.2 dBi (an improvement of 3.7 dB or 134%). Conventionally, such a gain enhancement would 5 times increase in its dimensions (flaring). However, the authors achieve the same with only 2 times increase in dimensions. Another interesting value addition of the proposed idea is that an FSS sheet can be added to the existing horn antenna to increase its gain without altering the antenna itself. Such a scheme is highly beneficial in strategic applications. The proposed gain enhanced horn antenna can be recommended to be utilised in several X-band applications, such as radar systems (weather, surveillance, traffic control and military), satellite communications and point–point microwave links that require high gain and small form factor.