A wideband open-slot antenna with high front-to-end ratio

A new design of open-slot antenna with a high front-to-back (F/B) gain ratio is proposed in this work. In order to enhance unidirectional radiation characteristics of the open-slot antenna, a two-element array and a pair of symmetrical notched slits are utilized. The two-element array achieves a power combination and increases the front-endfire radiation gain. The pair of symmetrical slits acts as a power reflector, which suppresses the backward radiating power. In addition, three arrays of eight-element metal strips are added and used as a power director so that the forward power and the F/B ratio of the open-slot antenna can enhance. From the measured results, the proposed antenna demonstrates a F/B ratio of 22.3 dB and possesses superior unidirectional radiation performance.