Measurement and modeling of radio wave propagation characteristics for microcells in dense urban areas

To investigate the radio wave propagation characteristics within dense urban microcell scenarios across a 2-18 GHz wide bandwidth, essential for future 5G communication base station planning and resource allocation, this study has developed an automated measurement system capable of real-time recording of geographical location and spectral data. Experiments to measure the propagation characteristics of microcellular radio waves were designed and conducted. A localized statistical propagation model that accounts for building absorption losses was proposed. Initially, a path loss base model was constructed in accordance with recommendations from the International Telecommunication Union Radiocommunications sector (ITU-R). Typical microcell scenarios were selected, and building vector information for the experimental sites was extracted using the OpenStreetMap open-source mapping platform. Information exchange between real-time kinematic (RTK), spectrum analyzers, and computers was realized through Matlab. The model parameters were calibrated based on the measured data, and a correction term that considers building absorption losses was added, culminating in the localization of the model. The experimental results indicate that the automated measurement system assembled in this study is capable of stably and accurately collecting relevant data. The localized propagation prediction model for dense urban microcells constructed herein can reduce the standard deviation of the error to as low as 5 dB, providing new testing methods and a model basis for researching radio wave propagation characteristics in complex environments and for the application of future 5G base station planning.