Satellite-to-Ground FSO System Based on Multiaperture Receivers as an Optimization Solution for Strong Turbulence and Fog Conditions

AbstractSatellite-to-Ground Downlink-Free Space Optics (SatGD-FSO) communication systems are emerging as the key driver for telecom investment, with several factors driving this convergence. It is attractive to minimize the size, weight, and power profiles of the space terminals by utilizing high affectability and huge accumulation collection zone ground terminals. Multiaperture coherent receivers using spatial diversity approached is considered on the attractive solution can fulfill this necessity and have numerous focal points over the single enormous opening cognizant recipients. The effects of atmospheric and climatic conditions using various dynamic system parameters have been investigated as a function of bit-error-rate (BER) performance of multiaperture coherent receivers. Types of orbits, aperture averaging, zenith angle, transmit optical power, and modulation schemes are systematically investigated and compared to the SatGD communication system. The proposed solution with a maximum throughput of 2.5 Gbps is useful for a plan and optimization improvement of the SatGD-FSO systems.

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Prediction of Received Optical Power for Switching Hybrid FSO/RF System

Electronics ◽

10.3390/electronics9081261 ◽

2020 ◽

Vol 9 (8) ◽

pp. 1261

Author(s):

Renát Haluška ◽

Peter Šuľaj ◽

Ľuboš Ovseník ◽

Stanislav Marchevský ◽

Ján Papaj ◽

...

Keyword(s):

Optical Communication ◽

Free Space ◽

Communication Systems ◽

Prediction Models ◽

Optical Power ◽

Free Space Optics ◽

Communication Line ◽

Atmospheric Transmission ◽

Space Optics ◽

Weather Information

This study deals with the problem of fiber-free optical communication systems—known as free space optics—using received signal strength identifier (RSSI) prediction analysis for hard switching of optical fiber-free link to base radio-frequency (RF) link and back. Adverse influences affecting the atmospheric transmission channel significantly impair optical communications, therefore attention was paid to the practical design, as well as to the implementation of the monitoring device that is used to record and process weather information along a transmission path. The article contains an analysis and methodology of the solution of the high availability of the optical link. Attention was paid to the technique of hard free space optics (FSO)/RF-switching with regard to the amount of received optical power detected and its relation to the quantities influencing the optical communication line. For this purpose, selected methods of machine learning were used, which serve to predict the received optical power. The process of analysis of prediction of received optical power is realized by regression models. The study presents the design of the optimal data input matrix model, which forms the basis for the training of the prediction models for estimating the received optical power.

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Hybrid POF/VLC Links Based on a Single LED for Indoor Communications

Photonics ◽

10.3390/photonics8070254 ◽

2021 ◽

Vol 8 (7) ◽

pp. 254

Author(s):

Juan Andrés Apolo ◽

Beatriz Ortega ◽

Vicenç Almenar

Keyword(s):

Optical Power ◽

Industrial Applications ◽

Free Space Optics ◽

Polymer Optical Fiber ◽

Hybrid Fiber ◽

Modulation Formats ◽

Space Optics ◽

Indoor Communications ◽

Power Measurements ◽

Good Agreement

A hybrid fiber/wireless link based on a single visible LED and free of opto-electronic intermediate conversion stages has been demonstrated for indoor communications. This paper shows the main guidelines for proper coupling in fiber/air/detector interfaces. Experimental demonstration has validated the design results with very good agreement between geometrical optics simulation and received optical power measurements. Different signal bandwidths and modulation formats, i.e., QPSK, 16-QAM, and 64-QAM, have been transmitted over 1.5 m polymer optical fiber (POF) and 1.5 m free-space optics (FSO). Throughputs up to 294 Mb/s using a 64-QAM signal have been demonstrated using a commercial LED, which paves the way for massive deployment in industrial applications.

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