The stability analysis of the hybrid thin-slot algorithm

Sub-cellular FDTD algorithms for modeling thin slots in conductors have previously been developed. The integral-equation based hybrid thin-slot algorithm (HTSA) has been shown to agree well with results of other methods for thin slots in planes. The HTSA can not only model slots having zero thickness but that having depth. However, instability occurred for some cases when the method is used. In this work, the stability of the HTSA is analyzed with different slot width, depth, and length, and the source effect on the stability has also been studied. The analysis shows that the HTSA is best for short, narrow and thick apertures, and when long, wide, thin slots are involved, other ways should be occupied.