This article proposes a receiving device in which arbitrary input signals are subject to pre-detector processing for the subsequent implementation of the idea of compressing broadband modulated pulses with a matched filter to increase the signal-to-noise ratio and improve resolution. For this purpose, a model of a dispersive delay line is developed based on series-connected high-frequency time delay lines with taps in the form of bandpass filters, and analysis of this model is performed as a part of the radio receiving device with chirp signal compression. The article presents the mathematical description of the processes of formation and compression of chirp signals based on their matched filtering using the developed model and proposes the block diagram of a radio receiving device using the principle of compression of received signals. The proposed model can be implemented in devices for receiving unknown signals, in particular in passive radar. It also can be used for studying signal compression processes based on linear frequency modulation in traditional radar systems.

This article considers the peculiarities of using circular orthogonal polarization basis for measuring the parameters of an electromagnetic wave. In particular, the angle of inclination of the major axis of the polarization ellipse and the ellipticity coefficient are among measuring parameters. The main expressions for calculation of field parameters in circular and linear orthogonal polarization basis are developed and analyzed. The advantages of using the ring as a measuring antenna in comparison with symmetrical vibrators of the turnstile antenna are substantiated. The expressions obtained in the article for calculating the measurement errors of polarization parameters in a linear orthogonal polarization basis illustrate the multifactorial dependence of the measurement accuracy on the angular and amplitude parameters. In contrast to the linear polarization basis, in case of circular basis, the inclination angle of the polarization ellipse axis can be found by direct measurements of the phase shift, and the accuracy of measuring the ellipticity coefficient is affected only by the error of measuring the ratio of voltage amplitudes, which are proportional to the modules of the field strength vectors of the left and right directions of the circular polarization rotation. This provides better potential accuracy of measurement for the electromagnetic wave parameters when using circular polarization antennas and, correspondingly, more reasonable analysis in the circular orthogonal polarization basis.

This article is devoted to the analysis of prospect to apply multifunctional adaptive antenna systems for radio monitoring stations. The review of publications done demonstrates that current antennas that are developed and used in radio monitoring systems to control and measure the parameters of electromagnetic radiation should be applicable to conduct accurate measurements in wide frequency range under the condition of interferences. The analysis shows that modern adaptive antenna systems are mostly developed for radar and telecommunications applications. In this context we consider possible ways to solve the problem of adapting radio monitoring devices to a complex electromagnetic environment using antenna systems with primary processing of received signals . It was found that the developers of the antennas, which are based on adaptive interference suppression methods, focus basically on the development and implementation of adaptation processes, limiting themselves only to solving electromagnetic compatibility problems. In such approach, the functions of direction finding and measurement of radiation field parameters important exactly for radio monitoring systems are mostly ignored. Therefore, this research area opens up a wide field for identifying new possibilities for constructing multifunctional antenna systems. Focusing on this direction of research, we consider as an example the constraction of a simple two-element adaptive antenna system, which can be used to measure the parameters of the electromagnetic field in radio monitoring systems. The main relations for the error of determining the direction of arrival of the interference signal with a simple two-element antenna are investigated. The influence of the stability of the antenna array parameters and functional units of signal processing onto the errors is estimated.

This paper proposes a new approach to estimating the contour of the coverage zone for a cellular communications base station that takes into account meaningful reflecting objects located out of the considering zone. Based on this approach, the procedure for modeling and designing the cellular system coverage area. Unlike known methods, the developed procedure considers the influence of electromagnetic wave reflection from external details of the relief, in particular essential reflecting objects located outside the considered cell. The effect of the external objects on the formation of the coverage area resulting contour is considered analytically, numerically and experimentally. The proposed solution leads to more accurate designing of the coverage area for each cell. This creates the opportunity for further development of designing techniques to more effective engineering solutions at developing and applying cellular communication systems in real situations and at various scenarios.