zahra mansouri

i used a mode source for exciting this waveguide and i set it in the bottom of the waveguide in +z direction that is along the propagation direction. i used only one source. i wanted to analyze the propagation and power of a special mode along this waveguide. i want use a 4micron lenght of this waveguide for a device so i wanted to full analyze this in fdtd solution. for simulation in fdtd i set the waveguide lenght to 9 micron and put some cros sectional and longitudinal power monitor and two expansion monitor along the waveguide. i didnt investigate how to excite it in experiment yet. now i am only studing some features of this waveguide. i meant the ration of p2/p1 for transmittion. with using the data of the mode expansion monitor i get t forward much smaller than t backward. what u mean from cavity? is your meaning that i should continue the waveguide out of the fdtd region and i put the source in the out of the simulation boundary?