| Abstract [eng] |
The use of Unmanned Aerial Vehicles (UAV) areas is highly increasing. One of the newest use of the areas of the UAV is the research of meteorological characteristics. The research is very important and necessary in the presence of hazardous meteorological conditions. Currently such systems as radiosondes, dropsondes, weather radars, satellite systems, or human-piloted aircrafts are used, they have many advantages, and however, there are disadvantages as well. The use of air-deployed UAV could expand the range of the research, but also the disadvantages of other previously mentioned systems could be avoided. Dropsonde is the most suitable system to gather date in low layers of the atmosphere, especially in storm clouds. Such a system could use the body of octahedron in a combination with a streamer tail. The most common problem is the transmission of the gathered information to the ground station in real-time. It is related to radio waves, which transmit the information, sensitivity to various external factors such as humidity, temperature, noises, fading, etc. That is why it is necessary to anticipate the propagation of radio waves at the design stage of the air-deployed UAV which gathers and transmits the information in real-time. In this research, based on the electromagnetic wave statistical characteristics, the losses of signal propagation are predicted, evaluating the influence of rain, clouds, and path losses. The proposed model is based on a normal distribution stochastic differential equation. This model can accurately describe the loss of the propagation path by selecting a free member ε, nevertheless, the predicted propagation losses are very sensitive to the change of the free member ε. The created model is compared with the experimental results and with other authors' research. In this work, the measurement was made with the drone in normal weather conditions and in low altitudes. The results obtained demonstrate great compliance with the model. Further analysis can concentrate on the full measurement of the low layer of the atmosphere achieving 2-3 km in both normal and hazardous weather conditions. These measurements are essential in creating ε alteration model. The accomplished model was suggested during the 23rd International Scientific Conference Transport Means 2019. |
