Path Loss Model in RIS scenario

Vienna 5G Link Level Simulator
1

Hi sir,
I actived scStr.topology.geometricLayout =true
and use pathloss model type =urban
what effect does these prameters when choose urban scStr.simulation.pathLossModel.alpha = 1;
scStr.simulation.pathLossModel.alpha2 = 3.9;
scStr.simulation.pathLossModel.breakDistance = 50;
scStr.simulation.pathLossModel.averageBuildingHeight = 1
when i choose position for RIS [x,y,z] ex: [200,100,20]
does z=20 for BuildingHeight because ris on height 20m
best regards
Roaa

2

Dear Roaa,

It means that the building’s height is 1 meter, and the RIS is at 20 meters, and therefore the RIS is 19 meters above the rooftop.

To see how this is calulcated, open the file +Parameters/SimulationParameters.m and scroll down to line 2457. There you find how these values are used, and what 3GPP document / section the calculation follows.

Best regards,
Bashar

3

Thanks for response, i want to question about alpha when chose pathloss exponent for urban from 2.7 to 3.5 ,the throughput becomes =zero why ??

4

With the higher exponent the path loss becomes higher, and therefore the recevied signal becomes too weak to be detected. In this case, higher transmit powers should be used, or you should lower the modulation order and code rate used.