Pulse input Rectangular Waveguide

Hi everyone,

Is it possible in comsol to give a pulse shape input to a port of rectangular waveguide as a power source.? Actually I want to heat a certain material inside a rectangular waveguide for some time (say for 0-10s) and after 10s (say for 10-20s) see its cooling behaviour, that how much the material retain its temperature after turning off the power.?? Just like the microwave oven Problem.

Is there something like this possible in comsol.??
Can someone open the discussion forum and help me.??

Thanks in advacne..