Analysis and Optimization: interference study of 900MHz NR system to NB-IoT system

In this study, we focus on exploring the potential interference to neighboring-frequency NB-IoT systems caused by the evolution from LTE to 5G NR systems in the 900 MHz band. In particular, the study focuses on the base station and terminal transmissions of the 900MHz 5G NR system and analyzes their potential interference impact on the indoor and outdoor terminals of the neighboring-band NB-IoT system as well as on the base station reception. In the future 900MHz 5G system, the base station is expected to have a transmit parameter of 4*60W. We meticulously list the key base station and terminal parameters required to perform system analysis and interference calculation based on the 3GPP standard. In this thesis, we have thoroughly explored the specific mechanism of neighbor frequency interference through a comprehensive approach of experiments, simulations and reference standards, and based on which we have proposed effective optimization strategies. These strategies aim to reduce the interference of the 5G NR system to the neighboring frequency NB-IoT system, thus ensuring that the two systems can coexist harmoniously in the same frequency band. The results will provide theoretical support and practical guidance for the smooth transition from LTE to 5G NR in the 900 MHz band, which is of great significance for realizing a more efficient and stable communication network.