Engineering and Technology Journal

Performances Study of PSK and ASK Modulation Technique under Atmospheric Turbulence in FSO Communication System

Esraa K. Al – Gazzi; Ekbal H. Ali; Assel J. Mohammed

Volume 42, Issue 2 , February 2024, , Page 276-287

https://doi.org/10.30684/etj.2023.143196.1567

Abstract

The performance and reliability of a free-space optical (FSO) communication system can be greatly increased using various methods. The primary goal of each technique is to reduce the ... Read More ...

Design Analysis of A Compensation Technique In FSO Communication System to Mitigate Atmospheric Turbulence Effect

Jenan A. Kalati; Shehab A. Kadhim

Volume 37, 3B , December 2019, , Page 82-85

https://doi.org/10.30684/etj.37.3B.3

Abstract

Free-space laser communication systems usually experience strong channel fading caused by atmospheric turbulence. To mitigate the impact of atmospheric turbulence on free-space optical ... Read More ...

Limitation of Laser Satellite Communication Due To Vibrations and Atmospheric Turbulences

Tarq A.Mohhmad

Volume 28, Issue 23 , November 2010, , Page 6718-6731

https://doi.org/10.30684/etj.28.23.10

Abstract

In this research, we analyze the effects of vibrations and the atmospheric onturbulence for a broadband laser satellite down link (BLSDL). The use of opticalradiation as a carrier between ... Read More ... In this research, we analyze the effects of vibrations and the atmospheric onturbulence for a broadband laser satellite down link (BLSDL). The use of opticalradiation as a carrier between satellites and in satellite-to-ground links enablestransmission using very narrow beam divergence angles. Due to the narrow beamdivergence angle and the large distance between the satellite and the groundstation or any object the pointing is a complicated process. Further complicationresults from vibration of the pointing system caused by fundamental mezchanisms: tracking noise created by the electro-optic tracker and vibrations caused byinternal satellite mechanical mechanisms. Additionally an in homogeneity in thetemperature and pressure of the atmosphere leads to variations of the refractiveindex along the transmission path. These variations of refractive index as well asintroducing other external noise, pointing vibrations, can cause fluctuations in theintensity and the phase of the received signal leading to an increase in link errorprobability. In this research, we develop a bit error probability (BEP) model thattakes into account both pointing vibrations and turbulence-induced high amplitudefluctuations (i.e., signal intensity fading) in a regime in which the receiveraperture antenna (Do) is smaller than the turbulence coherence diameter (do), theresults indicate that the satellite broad band laser down link with the receiver canachieve a BEP of 10-9 and data rate of lGbps with normalized pointing vibration ofand turbulence withAfter reducing these limitation of laser satellites and compensatesrelatively most atmospheric error probabilities due to atmospheric turbaulences(BEPS) or variation of refractive index by using for ward feeding under finetracking which designed to decrease the residual jitter influencies or by usingdirectional laser beam or introducing feeding forward compensation method andadaptive techniques to reduce the effect of system vibrations [12].

Keywords = atmospheric turbulence

Performances Study of PSK and ASK Modulation Technique under Atmospheric Turbulence in FSO Communication System

Abstract

Design Analysis of A Compensation Technique In FSO Communication System to Mitigate Atmospheric Turbulence Effect

Abstract

Limitation of Laser Satellite Communication Due To Vibrations and Atmospheric Turbulences

Abstract