Leaky Wave Antenna Using Composite Right/Left- Handed Transmission Line with Rectangular Feeding Structure

A leaky wave antenna (LWA) using composite right/left-handed (CRLH) transmission line (TL) composed of ladder network has been investigated [1]. The effect of transmission line length and height on the gain and bandwidth is clarified in [1]. In order to increase the gain of the LWA, mushroom-shaped unit cell has been investigated in [2]. Chip capacitance is used for series capacitance. The bandwidth of 113% and the maximum gain of 1 dBi at 1.6 GHz are achieved experimentally in the case of three cells (0.32λ) in [2]. In order to reduce the size of LWA for the application of cellular phones or mobile devices, this paper proposes the mushroom-shaped unit cell with parallel plate capacitance and rectangular feeding structure in the case of two cells. Moreover, the simulation results are verified by using the measured transmission characteristics and radiation characteristics.