Composite Right/Left-Handed Leaky Wave Antenna with structurally non-periodic unit cell arrangement

A unique dominant mode structurally non-periodic Composite Right/Left-Handed (CRLH) Transmission-Line (TL) based Leaky Wave Antenna (LWA) is proposed, with a novel kind of unit cell arrangement, which utilizes the additional degree of freedom obtained from non uniform spacing between the unit cells to control the radiation behavior of the antenna. We investigated the influence of non uniformly spaced unit cell arrangements on the radiation performance of the CRLH LWA and determined an optimum unit cell arrangement which leads to an improvement of 3 dB in side lobe level (SLL) suppression when compared to its structurally periodic counterpart for broadside direction. Furthermore, various aspects which are critical and should be taken into consideration while designing a structurally non-periodic LWA comprising of non uniformly spaced unit cell arrangement are also addressed.