Real Measurements and Evaluation of the Influence of Atmospheric Phenomena on FSO Combined with Modulation Formats
Journal Title: Elektronika - Year 2016, Vol 20, Issue 2
Abstract
The influence of atmospheric environment is fundamental for Free-Space Optical link (FSO). The atmosphere can significantly degrade the communication quality of FSO up to so low received power/RSSI level that it can lead to the loss of communication. For this reason, authors used a professional weather station built on site of FSO link for measurement of real atmospheric conditions such as wind speed, temperature, relative air humidity, air pressure and solar radiation. Random changing of these atmosphere parameters creates atmospheric turbulences, absorption and dispersion centers. It is necessary to specify the value of refractive index structure parameter Cn^2 because it determines the influence of atmosphere on the FSO. The first part of this article includes the theoretical calculation of Cn^2, there are used two models PAMELA and Macroscale Meteorological model. The evaluation of the atmospheric influences and the RSSI value of received power level and also simulation of different types of modulation formats OOK-RZ, OOK-NRZ and BPSK in Optiwave is integral part of this article.
Authors and Affiliations
Jan Latal, Lukas Hajek, Ales Vanderka, Petr Koudelka, Stanislav Hejduk
Analytical modelling of the transient response of thermopile-based MEMS sensors
This work presents an analytical model dedicated to study of the transient response of multipurpose MEMS devices based on thermopile sensors. In general, thermopile sensors response depends on ambient temperature, therma...
Morlet Wavelet UDWT Denoising and EMD based Bearing Fault Diagnosis
Bearing Faults in rotating machinery occur as low energy impulses in their vibration signal and are lost in the noise. This signal has to be properly denoised before analyzing for effective condition monitoring. This pap...
Vector-Controlled Induction Motor Drive with Minimal Number of Sensors
This paper proposes an improved and robust induction motor drive control method which uses minimal number of sensors, providing only dc-link current measurement as a feedback signal. The proposed dc-link current sampling...
Study on New Smart Transformer Terminal Unit Based on ARM and GPRS Network
Distribution transformer is one of the most important power equipments in distribution network, whose running state exercises a great influence on the stability of the network. Transformer Terminal Unit (TTU) is an effec...
From Theory to Development: Role of Multiphysics Modeling and its Effect on Education in Electronics
Electronics engineering is a very rapidly growingfield, as the time passes the requirement of more advance technologiesincrease. There are a lot of institutions and universitiesaround the world that provide quality educa...