Transverse resonance analysis of a planar leaky wave antenna with flexible control of the complex propagation constant
In this paper an efficient technique based on the transverse resonance network has been implemented to analyze a half-mode microstrip line loaded with two rows of periodic metallic posts. For this antenna a simultaneous control of both the phase constant β and the leakage rate a is achieved and therefore a tailored radiation pattern can be synthesized whereas a high radiation efficiency is kept. The radiation mechanism is similar to the conventional microstrip leaky-wave antenna operating in its first higher-order mode, with the novelty than the leaky-mode leakage rate can be controlled thanks to the addition of the periodic metallic posts. In order to characterize the impedance associated to the row of metallic posts an electric field integral equation EFIE based on the Green's functions one dimensional periodic current filament has been solved by the method of moments MoM. Several prototypes operating at 15 GHz have been designed and validated by using a commercial full-wave simulation tool with the purpose to demonstrate the operation principle and design flexibility of this leaky-wave antenna.