SPECIFICS OF THE ASSESSMENT OF EMC CONDITIONS FOR 5G NETWORKS
V.G. Skrynnikov, independent expert, Ph.D.; email@example.com
D.A. Paltsyn, FSUE GRFC, director of communications department; d. firstname.lastname@example.org
E.E. Devyatkin, FSUE NIIR, EMC Analysis Center, deputy director, Ph.D.; email@example.com
The main specifics of assessment of EMC conditions for 5G networks are considered. These features are formulated on the basis of the analysis of already known technical solutions planned for the creation of 5G NR (New Radio) radio interfaces.
Keywords: 5G/IMT-2020, NewRAT, NR (New Radio), propagation model, radio interface, electromagnetic compatibility (EMC).
SYNTHESIS OF ORTHOGONAL REAL SIGNAL WEYL-HEISENBERG BASIS BASED ON THE ALGEBRAIC APPROACH
An algebraic approach to the synthesis of optimal real Weyl-Heisenberg bases is presented. The selected optimal criterion provides orthogonality of signal basis and the smallest standard deviation of basis functions from the desired reference. In addition, the special algebraic structure of the synthesis algorithm in the form of multiplication of sparse matrix allows an efficient computational implementation and flexible adjustment of frequency-temporal resolution of the resulting basis. The results of the experiment, confirming the effective computational implementation, are given.
Keywords: Weyl-Heisenberg basis, synthesis of optimal basis, frequency-temporal localization, signal basis, computational implementation, time-frequency resolution.
PM-AM NOISE ANALYSIS OF HARMONIC OSCILLATORS USING DIFFERENTIALLY CONNECTED MOSFETS
The article is devoted to the development and investigation of harmonic oscillators using a pair of differentially connected MOSFETs. An algorithm of approximate theoretical analysis of stationary oscillations and PM and AM noises characteristics of such oscillators is offered. Relations for the calculation of regime and fluctuation characteristics of self-oscillators are obtained. The influence of the main sources of natural noise of a generator and current-supplying transistors on the total power spectral densities of phase and amplitude noises
Keywords: oscillator, field effect transistors (FETs), power spectral densities (PSD), phase (PM) noise, amplitude (AM) noise.
SYNTHESIS OF THE OFDM SIGNAL DISTORTIONS JOINT ESTIMATION ALGORITHM BY USING POLYNOMIAL SPLINES APPROXIMATION
N.Eu. Poborchaya, MTUCI, department of general theory of communication, associate professor, Ph.D.; firstname.lastname@example.org
A joint estimate of the channel and distortion of the OFDM signal appearing in the path of the direct conversion receiver is considered. The problem is solved in the time domain using the least-squares polynomial approximation with unknown laws of the noise distribution. The synthesized procedure allows you to simultaneously evaluate and interpolate a channel in frequency domain. The performed computational experiment showed the efficiency of the obtained algorithms, as well as the gain in the accuracy of estimation and noise immunity when using polynomial splines before approximation by polynomials.
Keywords: channel estimation, least square method, polynomial approximation, IQ-imbalance, constant components drift, OFDM signal.
COMPUTATIONALLY EFFICIENT REALIZATION OF THE COMPENSATOR OF DISPERSION DISTORTIONS ON THE BASIS OF THE DIGITAL FILTER BANK
E.O. Lobova, MTUCI, science research department, engineer; email@example.com
The article describes the computationally efficient dispersion distortion compensator based on a digital filter bank, a theoretical analysis of its frequency response, and simulation results. The compensator is implemented by introducing additional compensation delays, phase shifts, and interpolation filters into the channels of the synthesis of a classic bank of digital filters, determined by calculation depending on the slope of the dispersion characteristic of the ionospheric channel. The computational efficiency of the compensation algorithm is achieved by reducing the number of multiplication and addition operations due to the unified polyphase
structure of the synthesis filters and the analysis and application of the fast Fourier transform algorithm.
Keywords: frequency dispersion, wideband signal, distortion, filter bank, ionosphere, decameter range.
METHOD OF FREQUENCY SYNTHESIS WITH PHASE SPLITTING IN PLL. PART I
V.I. Koslov, independent researcher, Ph.D.; firstname.lastname@example.org
It is considered a new method of frequency synthesis, which consists in splitting the phases of the reference and signal pulse sequences in a phase-locked loop (PLL) system, followed by their phase comparison in a multi-frequency phase detector (MFPD) to obtain a control signal
for the PLL system. The described method allows the construction of frequency synthesizers with excellent characteristics of the spectral purity of the signal and agility, with a high-frequency resolution, low power consumption, and cost that is necessary for modern telecommunication and measuring radio equipment. The first part of the article considers the idea of phase splitting, the structure of MPFD for two types of synthesizers — PDS and PDS-DSM, the principle of operation and the static characteristics of the MPFD.
Keywords: frequency synthesizer, spectral purity, agility.
SPECTRAL AND SPATIAL EFFICIENCY OF HIGH-SPEED INFORMATION TRANSMISSION OVER OPTICAL FIBERS
V.N. Korshunov, JSC VNIIKP, chief researcher, Dr. Sci.(Tech.).
I.A. Ovchinnikova, JSC VNIIKP, head of the telecommunication cable and wire division, Ph.D.;
The concept of determining the efficiency of information transmission over cabled optical fibers is systematized. A complex of modifications of spectral efficiency and spatial efficiency is constructed. Analytical expressions for the calculation of information transmission rate
are given. Examples are given.
Keywords: optical fiber, optical cable, spectral efficiency, spatial efficiency, spectral-spatial efficiency.
A METHOD OF SIGNAL MODULATION AND DEMODULATION
Yu.M. Veshkurtsev, Institute of radio electronics, service and diagnostic (Omsk), president, head of the department of monitoring and measurement, professor, Dr.Sci.(Tech.); email@example.com
It is proposed to modulate the signal characteristics, in particular, the characteristic function, which is strictly defined for the signal. A new method of modulation and demodulation of a quasi-deterministic signal with random values of the amplitude and phase type is proposed, protected by patents and theoretically described. The scheme of the modem is constructed. The noise immunity of the modem in the channel with noise is theoretically investigated. The noise immunity of the modem in the range of signal-to-noise ratios of 100 dB is quantitatively estimated. It is shown that the modem has the maximum noise immunity, i.e. works without errors, in the range of 60 dB, starting from the signal-tonoise ratio, numerically equal to -20 dB and more.
Keywords: characteristic function, quasi-deterministic signal, method, modulation, demodulation, modem, noise immunity, signal-to-noise ratio.
PHASE-COMPENSATING PRINCIPLE OF SAMPLING OF ANALOG SIGNALS
A.N. Rudnev, FSUE STC Orion, chief engineer, Ph.D.; firstname.lastname@example.org
A phase-compensating principle of sampling of analog signals within the frequency band from 0 to Fh which provides the restoration of the initial signal according to its samples with the frequency of sampling Fs<2Fh, i.e. lower than Nyquist frequency.
Keywords: error probability, signal constellation, Voronoi diagram, Gaussian surface, numerical integration, basic function, volume of the figure below the surface.