This research investigates the propagation of radio frequency (RF) to make the wireless communication (Wi-Fi, 3G/4G, Bluetooth, mobile phone, smart-home) more reliable and easier to use. The research is mainly focused on the propagation of RF signals in indoor environments/inside the buildings as they are more prone to degradation due to obstacles e.g. walls, doors, furniture, people, but in particular insulation materials, double glazing and coated windows. The ideal solution would be to allow the best thermal insulation without compromising the wireless systems.
Therefore, the research main objectives include:
a) Understanding the theoretical and practical mechanisms of RF propagation (reflection, diffraction, scattering, and multi-path).
b) Investigating an impact of structural material properties on RF signals, to account for their effects.
To achieve these, the propagation models (3D/2D ray tracing, multi-wall) were initially investigated to understand their pros and cons. These models were implemented in MATLAB and enhanced for indoor environments. The model is inheriting its simplicity from multi-wall models, and its accuracy from complicated 3D ray tracing models. These are making it both easy and fast to use and more accurate in predicting the propagation.
To validate the model, several practical measurements were carried out using LoRa transceivers. LoRa is used as it is relatively novel long-range Internet of Things (IoT) solution that has many advantages. These includes: low power consumption, free to use, long range communication, vulnerable to Doppler Effect and multi-path propagation. It is concluded that the new model has a better accuracy owing to the implementation of the angle of the incidence and polarization of the beam into it.