Rounded Obstacle Diffraction Loss Model

This MATLAB function provides the diffraction loss calculated using the rounded obstacle diffraction loss model by adding a correction factor to the Knife Edge diffraction model by considering the diffractive obstacle as a rounded obstacle having a radius of curvature instead of the ideal knife-edge assumption. It works with single dominant obstacle in the path and it is built based on the Recommendation ITU-R P.526-15 [1]. This function uses a terrain data model to obtain the elevation profile between the transmitter and the receiver.

For more details, the reader can refer to the following article [2]. If you use this code in your work, please cite the following article:

M. M. Al-Zubi and M.-S. Alouini, "End-to-End Modelling and Simulation of NLOS Sub-6 GHz Backhaul via Diffraction for Internet Connectivity of Rural Areas," IEEE Open Journal of the Communications Society, 2023. https://ieeexplore.ieee.org/document/10306284

Output Parameters

An example illustrating how to use this function is attached here, i.e., “Example_Main.m”. This function provides the following output parameters:

|Parameter| Description| |:--|:--| |Lfs|free space loss in dB| |LKE|Knife edge diffraction loss in dB| |LD|rounded obstacle diffraction loss in dB| |L|total pathloss [L= Lfs + LD] in dB| |d1|the distance from the TX antenna to the top of the obstacle in m| |d2|the distance from the RX antenna to the top of the obstacle in m| |h|the distance from the top of the obstacle to the LOS line that connects the two antennas in m (h is negative if the obstacle is below this line)| |R|the obstacle radius of curvature in m| |F1|1st Fresnel zone radius at obstacle location in m| |F1max|maximum 1st Fresnel zone radius at the mid of path in m, i.e., d1 = d2| |d|distance between TX and RX in Km| |Theta|diffraction angle in degree|

Requirements

• MATLAB
• Mapping Toolbox
  
• Symbolic Math Toolbox
• Statistics and Machine Learning Toolbox
• Antenna Toolbox
• Communications Toolbox
• Phased Array System Toolbox

Output Sample

The user is expected to get results similar to the following:

Fig. 1: Site viewer

Fig. 2: Elevation profile between TX and Rx

Fig. 3: Output pathloss and corresponding parameters

References

[1] “Propagation by diffraction,” Int. Telecommun. Union (ITU), Geneva, Switzerland, ITU-Recommendation P. 526–15, 2019.

[2] M. M. Al-Zubi and M.-S. Alouini, "End-to-End Modelling and Simulation of NLOS Sub-6 GHz Backhaul via Diffraction for Internet Connectivity of Rural Areas,"IEEE Open Journal of the Communications Society, 2023.