Modeling of the Payload Signal Generator of the UAV Radio Transmitter based on the Phase Distortion Autocompensator

A block diagram of a payload signal generator of a UAV radio transmitter with an autocompensator for phase distortion of a digital computational synthesizer with improved spectral characteristics compared to known solutions is considered. Schematic diagrams and circuit design models of the main paths of the shaper in the Micro-Cap environment with the analysis of the characteristics of the necessary radio elements and microcircuits have been developed. The simulation of the device operation in the frequency domain is carried out. Based on the simulation results, the conditions for selecting the parameters of the shaper to achieve the greatest compensation of phase distortions are formulated

Theoretical and methodological foundations of provision of well-balanced development of forest sector of economy under the conditions of climatic changes and increase of anthropogenic stress

Current climatic changes are a threat to effective development of forestry under the modern economic conditions, which is aggravated by increase of anthropogenic stress in the sphere of forest use. Formation of strategies of well-balanced development of forestry supposes not only analysis of popular methodological approaches but formation of organizational mechanism for managing this sphere, the realization of which is aimed at preventive elimination of emerging threats. Provision of well-balanced development of economic system is viewed from the positions of the theory of management. The authors substantiate the use of complex approach which takes into account tendencies of functioning of forest sector, as a constant process of using forest resources, their preservation and renewal. Complexity will provide the study of the managed sub-system of forest complex (forestry) as totality, consisting of separate interconnected spheres of activities which possess their own functions and goals, with ordered and interconnected activities. Preventive approach will ensure timely revelation of key problems and threats to provision of well-balanced development of forest complex. Reflection will allow choosing the most effective instrumentarium for prevention (levelling) of emerging threats on the basis of existing experience. Balance of development is viewed as a feature peculiar for all structural components of economic system. It is advisable to distinguish the following factors which influence well-balanced development of region: group of natural and ecological, socio-political, economic, and social factors. Key components of provision of well-balanced development of economic system (forestry) could be presented from the positions of study, firstly, of managing and managed sub-systems; secondly, from the position of sub-system of forecasting, monitoring, identification, and evening-out of threats to well-balanced development.peer-reviewe

Borrowing Hydrogen Amination Reactions: A Complex Analysis of Trends and Correlations of the Various Reaction Parameters

Borrowing hydrogen or the hydrogen autotransfer amination is a powerful approach to create single C-N bonds starting from stable and readily available substrates: amines and alcohols. It is considered as one of the most atom-efficient and green methods to synthesize complex amines. Herein, we attempted to arrange the array of the existing data in a comprehensive and structured manner and determine correlations between the experimental conditions and catalysis outcome both within different groups of cata-lysts and between the defined groups using the machine analysis. For each type of N-nucleophiles (aromatic, aliphatic, and heteroar-omatic amines, amides) the most efficient working conditions were suggested including attributing the optimal base and temperature regime for each metal

Application of communication systems via the ultraviolet channel in FANET networks

The possibility of providing communication in difficult conditions on the basis of Flying Ad Hoc Networks (FANET) requires the use of non-electronic means of communication. It is proposed to use optical communication in the UV-C range in the absence of line-of-sight between the nodes of the FANET network. The general scheme of the optical transmitter and receiver of UV-C range is considered and the review of the components required for its implementation, taking into account the application possibility in highly mobile small-sized UAVs, is carried out. As a result of the analysis of FANET networks with UV-C channel, physical and channel level parameters critical for network performance are revealed. Methods of adaptive change of these parameters in the practical implementation of the UV-C communication system in FANET networks are proposed

Algorithms for analysis of stability and dynamic characteristics of signal generators at the physical level in FANET networks

To ensure the reliability of the physical level of Flying Ad Hoc Networks (FANET), the article substantiates the relevance of the study of stability and dynamic processes of signal formation and processing paths in the terminal and intermediate network equipment. The limitations of the known methods of the theory of automatic control, which make it difficult to perform the analysis of essentially nonlinear high-order signal generators, are shown. To analyze the stability of such formations proposed algorithm based on the use of the Nyquist criterion and approximation of the characteristic polynomial of a device by continuous piecewise functions; to analyze the dynamic characteristics of the algorithm based on spectral method of the input signal approximation and the frequency characteristics of a device by continuous piecewise functions

Application of communication systems via the ultraviolet channel in FANET networks

The possibility of providing communication in difficult conditions on the basis of Flying Ad Hoc Networks (FANET) requires the use of non-electronic means of communication. It is proposed to use optical communication in the UV-C range in the absence of line-of-sight between the nodes of the FANET network. The general scheme of the optical transmitter and receiver of UV-C range is considered and the review of the components required for its implementation, taking into account the application possibility in highly mobile small-sized UAVs, is carried out. As a result of the analysis of FANET networks with UV-C channel, physical and channel level parameters critical for network performance are revealed. Methods of adaptive change of these parameters in the practical implementation of the UV-C communication system in FANET networks are proposed

Algorithms for analysis of stability and dynamic characteristics of signal generators at the physical level in FANET networks

To ensure the reliability of the physical level of Flying Ad Hoc Networks (FANET), the article substantiates the relevance of the study of stability and dynamic processes of signal formation and processing paths in the terminal and intermediate network equipment. The limitations of the known methods of the theory of automatic control, which make it difficult to perform the analysis of essentially nonlinear high-order signal generators, are shown. To analyze the stability of such formations proposed algorithm based on the use of the Nyquist criterion and approximation of the characteristic polynomial of a device by continuous piecewise functions; to analyze the dynamic characteristics of the algorithm based on spectral method of the input signal approximation and the frequency characteristics of a device by continuous piecewise functions