How do I interpret path loss outputs for raytracing signal propagat... (2024)

% set antenna coordinates to be the east and west ends of McKeldin mall

tx1coords = [38.986700, -76.940278];

tx2coords = [38.985556, -76.940278];

rx1coords = [38.985833, -76.944167];

% register antennas

tx1 = txsite("Name", "McKeldin North Tx", ...

"Latitude", tx1coords(1), "Longitude", tx1coords(2), 'TransmitterFrequency', 2e8);%4e7

tx2 = txsite("Name", "McKeldin South Tx", ...

"Latitude", tx2coords(1), "Longitude", tx2coords(2), 'TransmitterFrequency', 2e8);

rx1 = rxsite("Name", "McKeldin Steps Rx", ...

"Latitude", rx1coords(1), "Longitude", rx1coords(2));

fprintf("Antenna sites built! \n")

% use a non free space terrain model

terrainModel = 'gmted2010';

% buildings

fprintf("Setting up 3D environment, this may take time... \n")

% https://www.mathworks.com/help/antenna/ref/siteviewer.html#mw_69390516-4cc4-43fb-abc0-6724ba77037e

% load osm data for college park

buildings = readgeotable("cpmd.osm",Layer="buildingparts");

% setup material dict

% this is a stock dict, this version of the cpmd osm use default material

materials = ["","brick","concrete","copper","glass","metal","plaster","stone"];

colors = ["#D3D3D3","#AA4A44","#D3D3D3","#B87333","#35707E","#151513","#FFFFFF","#301934"];

dict = dictionary(materials,colors);

% apply material properties (color in this case) to map

numBuildings = height(buildings);

for n = 1:numBuildings

material = buildings.Material(n);

buildings.Color(n) = dict(material);

end

% render site viewer with buildings and generate SINR map for smapling

viewer1 = siteviewer(Terrain=terrainModel,Name="Site Viewer (GMTED2010)", Buildings=buildings);

tx1.show(); tx2.show(); rx1.show();

fprintf("Building SINR map... \n")

sinr([tx1, tx2])

fprintf("Site build complete in " + toc + "sec \n")

% set propagation model

pm = propagationModel("raytracing");

% build path loss matrix

gammaPL = pathloss(pm,rx1,[tx1, tx2])

gammaPL =

2×1 cell array

{[69.3606 79.1522 84.4331]}

{[ 69.0560 84.3759]}

tx1coords = [38.988700, -76.940278];

gammaPL =

2×1 cell array

{[71.7899 72.0462]}

{[ 69.0560]}