# Experimental Study on LTE Mobile Network Performance Parameters for Controlled Drone Flights
## 2 Overview of Drone Realization for LTE Mobile Network Parameter Measurements
Additionally, the research in [40] shows the development of a model with a UAV that has a downward RX antenna and software-defined radio (SDR) software installed. The impact of a 3D antenna radiation pattern in UAV air-to-ground path loss is modeled, as well as RSRP parameters measured at altitudes of 30-110 m. Investigation of the applicability of LTE-M for network identification of unmanned aerial systems was shown in [41], where RSSI, RSRP, and RSRQ parameters were also measured at heights of 20-100 m. Lastly, the authors of the research in [42] described the development of a multirotor drone with a smartphone and drive-test application where RSRP and RSRQ parameter prediction models were described, and data from 65 to 125 m heights were shown. Based on the evaluated previous research [31; 33; 34; 35; 36; 37; 38; 39; 40; 41; 42], 3 GPP [43] recommendations, RTU and LMT previous experience, our experimental study, and data gathered and shown within this article, we have raised KPIs (see Section 3) for drone logistics using the LTE mobile network. From the research covered in the field of drone logistics and their wireless 4G and 5G coverage communication links, it is clear that different measurement applications have been studied and tested; however, there are no clear KPIs set for suitable network performance and the corresponding parameters that would be classified as acceptable for drone logistics and utilization. If there are some KPIs defined, they are usually not analyzed in-depth as to why specifically such values and rates have been set. In this research, the authors tackle this issue by analyzing large amounts of data to estimate appropriate KPIs, giving a detailed evaluation. Given the information mentioned in the previous paragraph, in order to improve the UAVs' (or in other words--drones') logistics as well as study their experimental performance in 4G and 5G adtalink environments (and their corresponding parameters), it is important to carry out extensive real-time measurements while applying different use-caseconditions. To achieve this, in this research, firstly we evaluated the appropriate industry practices, standards, and network parameters. Based on the collected and analyzed data, together with the Latvian mobile operator \"LMT\", we defined the main KPI indicators for the network's availability measurement and evaluation process. Then, experimental measurement setup, methodology, and application scenarios were developed and tested. Afterward, a vast amount of reference signal received power (RSRP), reference signal received quality (RSRQ), signal interference and noise ratio (SINR), uplink (UL), and downlink (DL) latency data was collected for the same route for four different altitude levels in the \"LMT\" mobile network. Measurements are carried out using a specially configured DJI M30 drone that carries the OnePlus NORD BE2029 mobile phone and Enhancell Echo One mobile network analyzer software. The gathered data and analysis made have a significant value for both mobile network infrastructure developers and mobile operators as well as the drone (UAV) manufacturing industry and logistic planners, allowing them to improve the performance of the operations. Our research process is structured into six main parts; thus, after the introduction, further sections of the paper are organized as follows. An overview of drone realization for LTE mobile network parameter measurements is described in Section 2. Mobile network parameter impact on the controlled drone logistics is described in Section 3. Section 4 discusses the experimental setup development for our research, while Section 5 focuses on the evaluation and analysis of the measured results. Finally, the results are concluded in Section 6.