Role of symmetries in periodic leaky-wave antennas, with emphasis on the double-asymmetry case

Symmetries play a major role in the properties of periodic leaky-wave antennas (LWAs). It was shown that symmetric LWAs have limitations when operating at the broadside frequency and that the key point to mitigate these limitations is to introduce asymmetry into the unit cell of the antenna structure, i.e. transversal or longitudinal asymmetries. This paper exploits a third type of asymmetry that combines the transversal and longitudinal asymmetries to further enhance the performance of LWAs.