Formation Analysis of Multi-Frequency Signals of Laser Information Measuring System

Abstract

Improving the accuracy of measuring motion parameters and the volume of information exchange with aircraft requires the modern development of multifunctional radio systems that allow the combination of information and measuring channels due to frequency (time) signal selection. However, radio systems have limitations on the number and accuracy of the measurement of aircraft motion parameters, as well as information transfer rates. These restrictions will make it possible to remove laser systems for measuring with high accuracy the parameters of motion of aircraft. Similar laser systems are widely used in transmitting information to stationary or quasi-stationary objects. As a result, there was a need to overcome the contradiction between the requirements for the technical characteristics of radio systems and the capabilities of the existing scientific and methodological apparatus for synthesizing the signals of laser information-measuring systems for monitoring the parameters of aircraft motion. The theoretical foundations of the formation and selection of laser signals for combining the information and measuring channels of laser information-measuring systems are proposed and investigated. A comparison is made with known methods of combining (combining) the information and measuring channels of radio engineering systems and the features of using a spectrum of laser radiation formed by pairs of longitudinal modes that “color” each channel signal for their selection at reception. When receiving optical pairs of longitudinal modes, the intermode beat frequencies turn into radio engineering subcarriers that are well filtered and selectable. Based on the results of mathematical modeling and combinations of longitudinal modes, the choice of elements of a modified selector of longitudinal modes of laser information-measuring systems is substantiated. This determines the importance and usefulness of work for applied systems for measuring the parameters of movement of aircraft.

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“…If the phase fluctuations are significant and their influence significantly exceeds that of the internal noise of the receiver, expression (18) has the following solution:…”

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Statistical analysis of harmonic signals for testing of Electronic Devices

“…Truncation to the first term of the serial expansion of the output signal, combined with assumption of high "signal-to-noise" (s/n) ratio, often results in acceptable predicted s/n ratios [12] - [15]. However, consideration of next expansion terms is obviously needed for essentially non-linear signals [16]. Statistical analysis of testing harmonic signals in terms of varying parameters is, thus, in demand.…”

Combined Method of Navigation Information Protection in Unmanned Aerial Systems Control Lines With Using Global Navigation Satellite Systems Ephemeris Modification Algorithm and Streaming Cipher

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