| Applicable Versions | NetSim Standard | NetSim Pro |
| Applicable Releases | v13.3 |
In a 5G network, gNBs are deployed to provide wireless coverage and service to UEs. In canonical models, gNBs are typically located at the center of hexagonal cells, which are arranged in a hexagonal pattern over a geographic area. Each gNB can serve multiple UEs within its coverage area, and UEs can also move between cells as they travel through the network. This is called the standard hexagonal cell model.
An SINR heatmap is a visualization that shows the spatial distribution of SINR values across a wireless network. The SINR value is the ratio of the strength of the desired signal to the strength of the interference plus noise in the same frequency band.
Standard hexagonal 7-cell model
The figure below shows an example of a standard hexagonal 7-cell model.
- At the center of each cell is a gNB.
- The coordinates of the gNBs are shown.
- The inter-site distance (ISD) - the distance between two adjacent gNBs - is set to 750m.
- A grid with a pitch of 20m is considered and UEs are placed at the grid points.
- Downlink (PDSCH) SINR is measured at each UE, and a heat map is generated.
Modeling SINR heatmap for the 7-cell Scenario in NetSim.
1. Open the bin directory where NETSIM is installed and double-click on Scenario_Generator.exe. This will open the Rapid Scenario Generator window.
2. Create a scenario with 1 UE, and 1 GNB with the desired properties. Change the following parameters. Copy gNB Coordinates.csv, and UE Coordinates.csv files generated by MATLAB code and paste them to the input file respectively.
Parameters | Values |
Grid Length | 4000 |
gNB Placement | File-Based |
UE Placement | File-Based |
gNB Properties | File-Based |
UE Properties | File-Based |
Simulation Parameters | Values |
Tx Power (dBm) | 40 dBm |
CA Type (TDD) | Single Band (n78) |
DL:UL Ratio | 4:1 |
Channel Bandwidth (MHz) | 10 |
Tx*Rx Antenna Count | 1*1 |
Pathloss Model | 3GPP |
LOS Probability | 1 |
Outdoor Scenario | Urban Macro |
Shadow fading | Off |
Beamforming | Off |
Downlink Interference | Exact Geometric Model |
3. Select the config file with the desired properties in the gNB and UE properties column. Change the desired icon type and click on OK. It will generate the Configuration file in the temp directory.
4. Import the config file generated by the Scenario Generator. Make changes in the Radio Measurements to log UE_x, UE_y. Enable Radio Measurements Logs from the logs in the GUI and run the simulation for .361 sec.
Scenario in NetSim
5. In the Radio Measurements Logs filter for time 0.36 seconds. Copy the x, y coordinates of UE and SINR that would be used for plotting the heat map.
Steps to plot the Heatmap in MATLAB
Make a vector of UE_x, UE_y, SINR and use the following code to plot.
tri=delaunay(UE_x, UE_y, );
h=trisurf(tri, UE_x, UE_y,SINR);
lighting phong
shading interp
colorbar EastOutside
xlabel('X Grid Points')
ylabel('Y Grid Points')
zlabel('SINR(dB)')
Fig: Plot of SINR heat map. SINR Range (-3 to 43 dB)
Similarly, we can plot a heat map for the standard hexagonal 19-cell model.
The figure below shows an example of a standard hexagonal 19-cell model.
- At the center of each cell is a gNB.
- The coordinates of the gNBs are shown.
- The inter-site distance (ISD) is set to 750m.
- A grid with a pitch of 50m is considered and UEs are placed at the grid points.
- Downlink (PDSCH) SINR is measured at each UE, and a heat map is generated.
Scenario in NetSim
Heat map plot for standard hexagonal 19-cell model
Useful links:
1. Overview of NetSim 5G library: https://tetcos.com/5g.html
2. NetSim 5G documentation (v13.3): https://www.tetcos.com/help/v13.3/Technology-Libraries/5G-NR.html