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This work describes the procedure for determining the expected values of UAV radio-heat contrasts () and discusses its angular dependences, as well as the estimation of UAV detection distances at four points cm and mm ranges (12 GHz, 20 GHz, 34 GHz, and 94 GHz). This paper reveals the pronounced frequency dependence on brightness temperature () and of a fiberglass unmanned aerial vehicle (UAV) made from composite fiberglass materials. The quantified experiments are conducted against a sky background under various weather conditions and wave ranges. The qualitative physical interpretation of these properties and their frequency dependence is proposed, reflecting the coefficient values and radio brightness of the background. The weak influence of weather on the observed UAVs in the X and Ku bands are demonstrated along with the multiple decreasing detection characteristics and advantages of the W band under bad weather conditions (the appearance of rain or thick cloud). This work presents data on the values of UAV contrasts, observed against the background of the sky and the regularities noted could be useful for predicting the effectiveness of the proposed radiometric detection and tracking system.

The telecommunication and radioelectronic systems with redundancy are widely used in different branches of human activity. To provide the necessary reliability level of equipment, the operation system is utilized. That system contains intended use, maintenance, repair, technical condition monitoring, and others. The damages, faults and failures are usually observed during the lifecycle of telecommunication and radioelectronic systems. They can lead to deterioration of equipment technical condition. The deterioration of technical condition can be detected during observation of diagnostic variable and reliability parameter. This article concentrates on the synthesis and analysis of statistical data processing procedure for deterioration detection while operating telecommunication and radioelectronic systems with redundancy. For the purpose of reliability estimation based on different redundancy methods, statistical data processing procedure synthesis was carried out using multiple hypothesis testing and detection criterion. The analysis problem was solved using Monte- Carlo simulation method, which allowed constructing operating characteristics. The obtained results can be used in the process of design and improvement of operation systems for telecommunication and radioelectronic equipment.

Safety of air transportation strongly depends on the performance of on-board positioning sensors. Positioning by data from navigational aids is considered by international aviation community as one of the main stand-by positioning approaches onboard of civil airplanes. However, only positioning by pair of distance measuring equipment (DME) meets requirements of Performance-Based Navigation. A DME service volume model based on path loss between a pair of transmitting and receiving antennas has been proposed in the paper. The model takes into account the influence of relief on radio waves propagation and diffraction from high-altitude elements of relief. The proposed model has been used in the analysis of DME global network performance. In particular, performance of a global network is analyzed based on availability area of DME service, area of positioning by pairs of DME/DME support, availability of particular positioning accuracy, and areas of meeting various RNAV requirements. Obtained results indicate that only in 27.76% of global airspace a DME service can be provided. However, only within 15.9% of airspace, a DME/DME positioning can be used. Results of the analysis indicate about the necessity of actions for further development of global navigational aids network in order to guarantee safe airlines connections around the globe.

Flight safety is an integral part of air transportation. Flight accidents are highly unlikely to appear but most of them are caused by the human factor. The aircrew training system for abnormal operations relies on integrated aircraft simulator-based exercises. Crew needs to be trained not to degrade piloting technique quality when facing increased psychophysiological tension. Therefore, methods evaluating the characteristics of ergatic aircraft control systems, warning systems for deterioration due to failures in avionics systems, piloting technique quality, and abnormal operation algorithms are necessary. An analysis of the bank angle has revealed that there are hidden increased tension manifestations in the human operator expressed in the transition of the flight parameter variation from a stationary random process to deterministic fluctuations in the form of a sinusoid. The goal of the research is to increase the efficiency of pilots’ training using integrated aircraft simulators based on the design and implementation of statistical data processing algorithms. To achieve the goal of the research, two algorithms for detecting deterministic fluctuations based on the Neyman-Pearson criterion and the optimal Bayesian criterion are developed. The presented algorithms can be used in the integrated simulator software to automate the decision-making process on piloting quality.

In this paper, the potentials of radar polarimetry to estimate wind speed is presented and discussed. The algorithm for wind speed estimate based on Weber numbers is demonstrated. The algorithm is based on the fact that liquid particles under the influence of wind can be bifurcated under the conditions of critical deformation. Using one the connection between backscattering from liquid hydrometeors and drop sizes in reflecting volume the information about the wind that causes the fission of the drops of particular sizes is extracted. The method of drop size evaluation with polarimetric radar is demonstrated and an algorithm for wind speed estimate on the base of Weber criterion, breakup conditions, and hydrometeors discrimination with similar polarization properties was proposed.

The operation system determines the efficiency of the intended use of radio equipment. The operation system includes radio equipment, documentation, operational resources, personnel, processes, data processing algorithms, etc. The operation process is associated with conditions of priori uncertainty of models, parameters, external factors, etc. The main element for monitoring is technical condition of radio equipment. In a general case, this condition can deteriorate. The problems of technical condition deterioration analysis can be considered in terms of changepoint study. The present paper concentrates on the problem of synthesis and analysis of method for changepoint detection during radio equipment operation. The detection algorithm is constructed based on Neyman–Pearson criterion with sample size accumulation. During algorithm synthesis the thresholds were calculated according to Bellman’s approach. The problem of synthesis and analysis was solved by two methods: analytically and using statistical modelling. The efficiency measures for this algorithm are the probability of correct detection and mean time of decision making. The proposed algorithm has advantages in mean time of decision making compared with CUSUM detection method.

The paper discusses the problem of statistical characteristics substantiation during radio equipment diagnostics. To provide serviceability and maintainability of radio equipment is one of the tasks of operation system. The operation system contains the processes of intended use of equipment, maintenance, running repair, continuation of life service and others. During running repair, the procedures of diagnostics, operability recovery and parameters monitoring are performed. The diagnostics process regulates the sequence of searching the failed element in the radio equipment scheme. The decision-making during diagnostics is associated with the errors of the first and second kind. So for efficiency analysis, the probability of correct diagnostics can be used. Such efficiency measure has random nature, but in the literature, only expected value is used to describe it. This paper concentrates on the approach to calculation of the probability density function for efficiency measure with purpose of obtaining the complete information about random value.

The paper deals with designing robust inertially stabilized platforms destined for functioning on the ground moving vehicles. The simulation model of the stabilization plant has been developed. The approach to the creation of the disturbances specific for ground vehicles is described. The algorithm of the design of the robust system has been developed. The basic steps of this algorithm are represented. Simulation of the synthesized inertially stabilized platform has been carried out.

Radio equipment for aircraft flight supporting consists of communication, navigation and surveillance devices. These devices are used to provide the safety and regularity of aircraft flights. During radio equipment operation the processes of intended use, maintenance, repair, continuation of life service are implemented. The decision-making about control and preventive actions for these processes is based on the results of statistical data processing. In such cases statistical methods with predetermined sample size are used. This paper concentrates on the problem of synthesis of sequential method that allows making decision faster for given level of data processing effectiveness. The researched sequential method is used for estimation of reliability parameters based on priory information about these parameters distribution and functional transformation of corresponding probability density function. During solving analysis problem, the probability density functions of estimate and observation duration are calculated.

Air transport services compose a continuously growing transportation industry, which became closer to their operational perils. Classical air traffic management system includes a network of flight routes for performing civil airspace operation. In our study, we provide an analysis of flight routes network configuration based on graph theory. Ukrainian flight routes network has been represented in the form of a weighted planar graph. Measures of weighted, closeness, betweenness centrality and waypoints degree are used for configuration analysis. Also, an edge vector was statistically analyzed for Ukrainian flight routes network. Results of analysis identify the most loaded and frequently used waypoints based on network configuration. Obtained data are useful for the development of Ukrainian flight routes network and efficient flight traffic planning procedures.