摘要

Controlling energy leakage is of great importance for users of surface-wave waveguides (SWGs) because it determines the propagating efficiency of surface waves. In this paper, a novel theoretical analysis of the energy leakage for these two types of SWGs is proposed, and the effects of some key parameters to the leakage such as the path width of the SWG and effective impedance of cell and incident angle are discussed more deeply. To verify the theoretical method, a model of the SWG consisting of 30 x 30 impedance-tunable cells driven by TM surface waves, whose impedance ranges from j370 Omega to j780 Omega according to our previous measurements, is simulated in HFSS. The simulation results are in good agreement with the theoretical ones, demonstrating that the leakage is inversely proportional to the width of the SWG and an increase of effective impedance of the guided path; furthermore, by using the impedance-tunable cells, the multi-functionality of the SWG is illustrated. The analyzing methods can be a guide for designing other SWGs without energy leakage, and as an inspiration for more complex SWG applications.