5G New Radio Signal Propagation and Ground-to-Air Channel Modeling at 3.565 GHz Based on Extensive Measurements

Abstract

This study delves into the intricacies of 5G New Radio (NR) signal propagation, and contrary to most existing literature, focuses on the 3.565 GHz commercial frequency band through extensive ground and airborne measurements. By assessing fundamental cellular network parameters such as Channel Power (CP), Field Strength (FS), Path Loss Exponent (PLE), and Shadow Fading Amplitude (SFA), the purpose of this investigation is to gain a verified and validated insight, in alignment with the 3GPP technical report, into the highly dynamic nature of 5G NR transmissions. Encompassing both Line-of-Sight (LOS) and Non-Line-of-Sight (NLOS) conditions at ground level, this research emphasizes realistic environments to provide precise empirical evidence on 5G signal behavior. This study further extends the current empirical knowledge base of 5G NR signal characteristics in the less-explored territory of higher-altitude signal dynamics by examining path loss and Small-Scale Fading (SSF) characteristics beyond altitudes of 120 meters, where a novel model characterizing the height dependency of PLE and fading phenomena is introduced. Notably, illustrating CP and FS for higher altitudes, this research unveils a novel and more accurate correlation between the Rician K-factor and altitude, demonstrating an increase with greater height. Significant findings from this research suggest that within the altitude range of 300–500 meters, the signal exhibits remarkable strength and stability, thus identifying this zone as ideal for capturing high-quality signals. These insights are pivotal in terms of their application in enhancing 5G cellular network coverage strategies and providing a reliable foundation for Ground-to-Air (G2A) channel models essential for Uncrewed Aerial Vehicle (UAV) communications.

Keywords

• 5G NR
• multi-altitudes airborne measurements
• 3GPP
• G2A channel model
• small-scale fading