Mathematical Models of Video-Sequences of Digital Half-Tone Images

This chapter is devoted to Mathematical Models (MM) of Digital Half-Tone Images (DHTI) and their video-sequences presented as causal multi-dimensional Markov Processes (MP) on discrete meshes. The difficulties of MM development for DHTI video-sequences of Markov type are shown. These difficulties are related to the enormous volume of computational operations required for their realization. The method of MM-DHTI construction and their statistically correlated video-sequences on the basis of the causal multi-dimensional multi-value MM is described in detail. Realization of such operations is not computationally intensive; Markov models from the second to fourth order demonstrate this. The proposed method is especially effective when DHTI is represented by low-bit (4-8 bits) binary numbers

Development of Nonlinear Filtering Algorithms of Digital Half-Tone Images

This chapter is devoted to solving the problem of algorithms and structures investigations for Radio Receiver Devices (RRD) with the aim of the nonlinear filtering of Digital Half-Tone Images (DHTI) representing the discrete-time and discrete-value random Markovian process with a number of states greater than two. At that, it is assumed that each value of the DHTI element is represented by the binary g-bit number, whose bits are transmitted via digital communication links in the presence of Additive White Gaussian Noise (AWGN). The authors present the qualitative analysis of the optimal DHTI filtering algorithm. The noise immunity of the optimal radio receiver device for the DHTI filtering with varying quantization and dimension levels is investigated

Signals of autodyne modules with external detection

Поступила: 12.12.2018. Принята в печать: 28.12.2018.Received: 12.12.2018. Accepted: 28.12.2018.Разработана математическая модель автодинного приемо-передающего модуля, связанного с антенной через одну или две детекторные секции. Получены основные соотношения для расчета его сигнальных характеристик при регистрации сигналов в цепи питания генератора и с помощью внешних детекторов. Показаны особенности формирования сигналов с внешних детекторов. Установлено, что их относительные фазовые сдвиги зависят как от величины коэффициента автодинного усиления генератора, так и от фазового расстояния между секциями. В случае высокого значения коэффициента автодинного усиления оба сигнала на выходе детекторов находятся в фазе. В случае малой величины коэффициента автодинного усиления на выходе диодов реализуется определенный сдвиг фаз между сигналами. Величина этого сдвига определяется относительным разносом между диодами в детекторных секциях. Получены условия формирования квадратурных сигналов. Экспериментальные данные получены на примере генераторных модулей, выполненных на диодах Ганна 8-мм диапазона.The mathematical model of the autodyne transceiver module, which is connected with an antenna through the one or two detector sections, is developed. The main mathematics for calculation of its signal characteristics at signal registration in the power supply circuit and with the help of external detectors, are obtained. The features of signal formation are demonstrated with external detectors. It is proved that their relative phase shifts depend both on the value of the autodyne amplification factor and on the phase distance between sections. In the case of the high autodyne amplification factor, both signals at the detector outputs are in-phase. In the case of low autodyne amplification factor, the definite phase shift between signals is realized on the diode outputs. The value of this phase shift is defined by the relative separation between diodes in the detector sections. Conditions of quadrature signal formation are obtained. Experimental data are obtained on the example of oscillation modules fulfilled on Gunn diodes of the 8mm-range

Calculation of autodyne parameters with the rigid characteristic of the active element conductance

Поступила: 01.03.2019. Принята в печать: 20.03.2019.Received: 01.03.2019. Accepted: 20.03.2019.Выполнены расчеты выходных, сигнальных и флуктуационных параметров и характеристик, а также параметров быстродействия автодинного генератора, находящегося под воздействием собственного отраженного излучения от объекта локации. Модель генератора представлена параллельным соединением проводимостей колебательной системы и активного элемента. Представлены результаты анализа зависимости указанных параметров и характеристик автодинов от режима работы генератора для случая жесткой характеристики средней за период колебаний проводимости активного элемента. Приведены для сравнения также результаты расчета для случая мягкой характеристики активного элемента. Результаты работы востребованы для инженерного расчета автодинных генераторов.Calculations of output, signal and fluctuation parameters and characteristics are made in the paper. The operation speed parameters of the autodyne oscillator, which is under the impact of the self-reflected emission from the radar target, are calculated. The oscillator model is presented by parallel connection of the oscillating system conductance and the active element conductance. The analysis results of the relationship between the mentioned parameters and autodyne characteristics upon the oscillator operation mode for the case of the rigid characteristic of averaged (for the oscillation period) conductance of the active element are discussed. The calculation results are given for the case of the soft characteristic of the active element for the comparison. These results are claimed for the engineering calculations of the autodyne oscillators

Influence of inherent parameter of stabilized UHF oscillators on autodyne response formation at a strong reflected signal

Results of an autodyne response analysis in UHF oscillators stabilized by the external high-Q cavity in the case of the strong signal when the reflected wave amplitude commen-surable with the own oscillation amplitude. Coupling between the basic operation cavity and the stabilizing cavity is implemented as a pass-reflecting filter with a resistive bond. Key relations are obtained, which describe the autodyne response to the own re-reflected radiation from a target. The load and oscillating system influence on autodyne response formation is fulfilled

The impact of resonator detuning on autodyne characteristics of stabilized microwave generators

The investigation results of formation peculiarities of the autodyne signal of stabilized UHF oscillators at the de-tuning of the oscillation frequency related to the natural frequency of the stabilizing resonator are given. The main mathematical equations are obtained, which describe the autodyne response to the impact of proper radiation reflected from the target. The calculation of the amplitude, frequency and amplitude-frequency characteristics of the autodyne system under various conditions are discussed. The experimental results obtained on an example of hybrid-integrated oscillator on Gunn diode of 8 mm-range are described. Experimental results quantitatively confirm the theoretical conclusions