LORA (Long Range) Based Low Power Emergency Tracking System in Disaster Areas

The communication network is one of the major assistances for disaster management purposes. At each disaster phase, the information flow between the disaster management departments and the population is critical, as it destroys the whole communication infrastructure where the base station to Mobile Switching Centre (MSC) connectivity is broken, power generators are exhausted, and the network may suffer from congestion. Even when radio equipment works, police officers, rescue teams, medical teams cannot communicate with each other because of incompatible radios. To analyze the characteristics of the geological environment in the disaster region and to alert the Disaster Management Department, this solution based on LoRa has been proposed. The penultimate goal of this paper is to fasten the rescue operations.

Dirty thunderstorms caused by volcano explosive eruptions in Kamchatka by the data of electromagnetic radiation

During volcano eruptions, so called dirty thunderstorms are the sources of electromagnetic radiation. They are caused by ash-gas clouds formed during explosive eruptions. Thunderstorm activity in an ash-gas cloud during volcano eruption is monitored by radio equipment. The VLF direction finder, located at Paratunka, monitors thunderstorm activity in the region of Kamchatka Peninsula including dirty thunderstorms accompanying explosive eruptions of Shiveluch and Bezymyanniy volcanoes. In the paper, we analyze records of electromagnetic radiation associated with dirty thunderstorms occurring during volcano eruptions from 2017 to 2020. During that period 24 eruptions of Shiveluch volcano and 5 eruptions of Bezymyanniy volcano occurred. Seventeen and three of them, respectively, caused dirty thunderstorms. Two-stage scenario of development is typical for all the dirty thunderstorms. The first stage lasts for 5–7 minutes and accompanies eruptive column development. However, if the eruption begins according to a smooth scenario, the first stage may be weak. The second stage lasts for 20–80 minutes and is associated with eruptive cloud formation and propagation. The intensity of this dirty thunderstorm stage depends on eruption power as well as on the interaction of an eruptive cloud during its propagation with the clouds of meteorological origin. Based on the obtained data, that is indicated by the increase of cloud-to-cloud stroke number.

TRENDS IN THE DEVELOPMENT OF UNMANNED AVIATION COMPLEXES AND THEIR RADIO EQUIPMENT

The issues of modern trends in the development of unmanned aviation complexes are considered. The main ways of their current and promising application are given, the main differences from pilot. The main ways of improving radio equipment of unmanned aviation complexes are considered. It is listed that in the near future, unmanned aerial vehicles will significantly affect the progress of military conflicts.

INCREASING THE RESISTANCE OF CONNECTORS TO EXTERNAL INFLUENCING FACTORS

The article is devoted to the issue of increasing the resistance of connectors used in radio equipment to external influencing factors. The paper analyzes the influence of external factors on connectors. We consider a technical solution that increases the reliability of connectors in radio equipment when exposed to harsh operating conditions.

PROCEDURE FOR ESTIMATING THE BOUNDARY DISTANCE OF SHORE RADIO STATIONS IN VHF RANGE FOR THE SHORE-TO-SHIP DIRECTION

Сформулирована и детализирована методика оценивания граничной дальности береговых ОВЧ радиостанций в направлении Берег-Судно, которая основана на зависимостях напряженности поля, полученных эмпирическим путем. Определены численные значения граничной дальности ОВЧ радиосвязи применительно к типовому судовому радиооборудованию и шумовой обстановке вблизи судовой антенны. Проведена оценка максимальных допусков определения граничной дальности ОВЧ радиосвязи. The procedure for estimating the boundary distance of the shore VHF radio stations in the shore-to-ship direction, which is based on the dependences of the electromagnetic field strength obtained empirically, has been formulated and detailed. Numerical values of the boundary distance of VHF radio communication in relation to typical ship radio equipment and the noise environment near the ship's antenna are determined. The estimation of the maximum tolerances for determining the boundary distance of VHF radio communication is carried out.

THE METHOD OF EVALUATING THE OPERATION OF RADIO TECHNICIANS OF SPECIAL PURPOSE IN EXTREME (CRISIS) SITUATIONS

In extreme (crisis) situations, tasks arise, requiring an answer to the question of the effectiveness of decisions made. When using radio technicians of special purpose, the results depend on both the ability of the equipment and its condition and from the service personnel. At the same time, it is necessary to take into account the presence of targeted interfering factors. The paper proposed a method for evaluating the operation of radio equipment for special purpose in extreme (crisis) situations, a distinguishing feature of which is to account for the mutual influence of the components of the system. The evolution of the basic component of operation is proposed to approximate polynomial dependence using a fuzzy logic apparatus when making resulting solutions.

5 G communication network signal propagation models

The next generation 5G / IMT-2020 technology, like any new technology, brings its own specific features to all aspects related to the practice of its application. One of these particularly important aspects is electromagnetic compatibility. At the stage of preparation for the introduction of 5G radio networks, called NewRadio, it is necessary to take early measures to assess effectively the electromagnetic compatibility conditions for these networks based on a thorough analysis of the features of 5G technology. Correct and accurate assessments of these conditions means successful provision of the electromagnetic compatibility of radio equipment of new networks. The World Radio Communication Conference WRC-15 identified new radio frequency bands for 5G, including centimeter and millimeter wave bands. In general, this RF spectrum is located in three regions: below 1 GHz, 1 GHz to 6 GHz, and above 6 GHz (up to 100 GHz). From the EMC standpoint, the following can be distinguished as the main features of this spectrum: different nature of losses during signal propagation, in particular, a significant influence of additional factors (gases – oxygen, water vapor, etc.) on the level of losses previously unknown in cellular communication. The mathematical model of signal propagation of 5 G communication networks has been developed which takes into account: the attenuation of signals in free space; attenuation of signals caused by the influence of walls and floor slabs, loss of signal energy, when space is filled with various objects; attenuation of signals caused by loss of energy of radio waves, when propagating through rains; signal attenuation due to loss of radio wave energy due to fog; signal attenuation, when propagating through tree leaves, slow and fast random fading.