How to accelerate the raytrace algorithm using gpu or other methods?

I had the city scenario loaded using siteviewer and defined tx,rx and propagation model rtmp as the example documentation said. The raytrace algorithms in the program takes tens of seconds or even hundreds of seconds. How should I accelerate these algorithm? Can it be done with gpu?

[添傲 陈]

In propagationModel, I have set MaxNumDiffractions to 0. This greatly increases the speed of the algorithm, but it is not enough.