Leaky-wave antenna based on microelectromechanical systems-loaded microstrip line

The authors suggest and theoretically study an efficient leaky-wave antenna (LWA) with beam scanning governed by micro-electromechanical systems (MEMS) capacitors. The use of MEMS instead of varactors or magnetised ferrite substrate allows one to significantly decrease losses. The LWA is implemented as a periodically loaded transmission line (PLTL). In order to obtain maximal possible dispersion of a PLTL, resonant loads combining variable capacitors and stub strap inductors are applied. Analysis of dispersion properties and design of a unit cell of the PLTL are based on the analytical model with further numerical optimisation. Full-wave simulations are carried out for a realistic beam-scanning LWA, where the radiated beam can transit from forward to backward directions for a practical MEMS design.