The paper presents an approach to the complex measurement of temperatureand mechanical strain for . Using a polyharmonic signal of a given shape allowed two sensors to be simultaneously polled. Temperature and mechanical strain sensors are made in the form of fiber Bragg gratings with special spectral characteristics.
Keywords: Bragg fiber grating, sensor, mechanical strain temperature, construction, photodetector, polyharmonic method, optical fiber, special form of the spectrum, light
The paper presents an approach to the complex measurement of temperature, humidity and electric arc for shields of complete switchgears. Using a polyharmonic signal of a given shape allowed two sensors to be simultaneously polled. Temperature and humidity sensors are made in the form of fiber Bragg gratings with special spectral characteristics.
Keywords: Bragg fiber grating, sensor, humidity, temperature, electric arc, complete cabinet, power distribution system, optical fiber, lens, light
The article demonstrates a computer model of a fiber-optic sensor implemented on the basis of a two-frequency optoelectronic generator (OEG) for measuring lateral pressure. In the loop of the optoelectronic generator, a fiber Bragg grating (FBG) with a phase shift is applied to which a transverse pressure is applied to guide the birefringence and create two orthogonally polarized transparency windows, which leads to the generation of two optical frequencies. The difference frequency of the beats between the two optical frequencies lies in the microwave range and depends on the magnitude of the pressure applied to the FBG. It was modeled that the sensitivity and the minimum detectable pressure are ~ 10 GHz / (N / mm) and 2.5 × 104 (N / mm), respectively. The high frequency and stability of the generated microwave component of the optoelectronic generator provide an extremely reliable and highly accurate measurement. Frequency survey allows the system to operate at high speed. In addition, the measurements are insensitive to changes in the ambient temperature and the wavelength of the optical carrier.
Keywords: transverse pressure, fiber optic sensor, fiber Bragg grating with phase shift, birefringence, optoelectronic generator, two-frequency optical signal with microwave frequency difference frequency
As a solution eliminating the disadvantage of wired home theaters - the multiplicity of signal and feed wires - a method of wireless power transmission is proposed to charge the batteries of the side and rear speakers at a frequency of 2.45 GHz. The energy of the microwave radiation is converted into energy for charging the batteries by means of a special receiving module. The receiver module includes a receiving antenna, a rectifier and a power controller. This article discusses the calculation of the receiving antenna for this system in the structure of a wireless home theater. For the simulation, an antenna of the Yagi-Uda type was chosen, for which the gain and the beamwidth were determined. During the first stage of the simulation, antenna parameters were obtained that were unsatisfactory in the width of the directional pattern. At the second stage, the antenna design was modernized and a re-simulation was performed. Based on the results of this, it can be concluded that the parameters of the receiving antenna improved by 1.5 times, while the gain factor increased by 13%.
Keywords: wireless home theater, wireless microwave power transmission, receiving module, Yagi-Uda antenna, simplified Landtapo dipole, patch antenna, antenna efficiency indicator, radiation pattern, gain factor, reflection coefficient
The questions of mathematical interpretation of results of trajectory measurements are discussed in terms of increasing the accuracy of identification of bearings of unmanned aerial vehicles during their movement in a "swarm" - a group. Variants of identification of horizontal and spatial bearings are offered. For each of the variants, criteria are proposed for identifying the belonging of the measured values to the same object in the group and the conditions for achieving them. The situation of false positives is shown. It is determined that additional identification measures are needed to eliminate false bearing triads and uncovered ambiguities, including the use of combinatorial exhaustive search algorithms. For their study, it is necessary to develop an experimental statistical model with an algorithmic description of cause-effect relationships, which is a further development of this work.
Keywords: " unmanned aerial vehicle, group of objects, bearing identification, horizontal bearing, spatial bearing, identification criteria, false notch"