Oleg V. Prokofiev

Bio: Oleg V. Prokofiev is an academic researcher. The author has contributed to research in topics: Pulse duration & Interference (communication). The author has an hindex of 1, co-authored 4 publications receiving 2 citations.

Additive Noise Effect on the Error of Time Interval Forming

Abstract: There are schematic solutions in electrical measurements and communication technique when information is transmitted in the form of duration of a time interval specified by a rectangular pulse. The reasons for the appearance of additive noise effecting the pulse duration are numerous and cannot be completely eliminated. These are caused not only by electromagnetic interference in the environment, but also by limitations in the characteristics of the electronic components of any operating principle including fiber optic transmission lines. The restrictions imposed by the noise on the accuracy of a time interval allocation were considered in this article. The additive model of the data signal and centered noise acting together upon the pulse shaper input are considered in the article. It is assumed in the model that the shaper conversion function is characterized by hysteresis that protects against false actuating. Some relationships between the distribution law form of the shaper response time, data signal form and noise statistical characteristics are revealed. It is obtained that moments of a shaper actuating are complied with the truncated Gaussian law. The time interval error is evaluated for cases when the front and slice of the pulse are determined by the moments of action of one shaper or some shaper with different noise statistical characteristics.

On How Harmonic Interference Does Influence the Forming of Pulse-Width Modulation Signal

Abstract: This paper is devoted to finding a relationship between harmonic interference on a data transfer and the pulse duration errors in transmitting an informative signal. Looking for a noise immunity in the case of pulse-width modulation makes sense if we can’t rely upon fiber-optic channels and other stationary equipment only. Surging interferences on a channel transmitting a pulse modulated signal result in a jitter on the leading and falling edges of the pulses. If the noise influence can’t be eliminated, a data transfer errors occur, inherent to the pulse-width modulation and other kinds of pulse modulation. At the time of making the paper, the authors were exploring a rationale for how the time lapse fixing errors are dependent on harmonic interference parameters. Here we give a grounding for the rule of the distribution law for the triggering moment of a rectangular pulse shaper. It is shown, that any straightforward measures are not enough to reduce these errors. The rule of probability density distribution of the time when the forming device gets triggered, is stated not only as a whole, many widespread cases are shown as well. The resulting analytics can be used both to find a trade-off between parameters of a device operating in a noisy condition, and as a measure of the pure theoretical limit pulse-width modulation as well.

Tone Image Processing with Discrete Data Structure

Abstract: The article focuses on the problem of image processing using a discrete data structure for tone images. The problem of conversion of continuous image into discrete form is considered. Two procedures are described: selecting a discrete grid for representing an image, and quantization, which consists in displaying luminance and color values in integers. The solution to the problem of selecting the visual display resolution and the number of levels of gray tone or colors when processing one-dimensional data is presented. A review of the transformation methods was carried out, after which the sample for both the one-dimensional case and the two-dimensional one was considered. The basis of the transformation methods was the Fourier and Hadamard transformations. These transformations are used in the design of filters designed to improve the quality of images, as well as in the implementation of data compression methods. They form the basis of image recovery from projections.