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Long Range Free Space Optical Links
Křivák, Petr ; Vlček, Čestmír (referee) ; Vašinek, Vladimír (referee) ; Wilfert, Otakar (advisor)
This dissertation thesis deals with a long range free space optical links for communication over the distance of few tens of kilometers in the atmosphere. The problematic of the beam propagation and atmospheric effects influencing the beam and the quality of the communication protocol are discussed. The measuring link is also designed to study the parameters of the communication link work conditions. The measuring link consists of two heads. The transmitter head is designed to use two optical beams with laser diodes at the wavelength of the atmospheric windows 850 or 1550 nm and the overall power of hundredths of mW. The receiver head includes the Fressnel lens. For the detection of very weak signal, the avalanche photodiode is used. In the end of this work, due to the high power of the transmitting optical beam, the laser safety conditions are also discussed, including the deduced optical transmitters construction recommendations.
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Modeling of the multichannel optical wireless link
Pavlů, Michal ; Fišer, Ondřej (referee) ; Poliak, Juraj (advisor)
This thesis deals with multi-channel wireless links with a higher range designated for free-space communications in an atmospheric media. Propagation of the optical beam in an atmosphere is analysed and various influences affecting the quality of the transmitted signal are described. The simulation is carried out for dual optical link. Link budget of individual paths working at the wavelengths in the atmospheric windows – 850 nm and 1550nm. It also examined optical intensity distribution of the transmitted beam. At the end of the work performed measurements and simulations verify the accuracy of the components used in wireless link.
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Long Range Free Space Optical Links
Křivák, Petr ; Vlček, Čestmír (referee) ; Vašinek, Vladimír (referee) ; Wilfert, Otakar (advisor)
This dissertation thesis deals with a long range free space optical links for communication over the distance of few tens of kilometers in the atmosphere. The problematic of the beam propagation and atmospheric effects influencing the beam and the quality of the communication protocol are discussed. The measuring link is also designed to study the parameters of the communication link work conditions. The measuring link consists of two heads. The transmitter head is designed to use two optical beams with laser diodes at the wavelength of the atmospheric windows 850 or 1550 nm and the overall power of hundredths of mW. The receiver head includes the Fressnel lens. For the detection of very weak signal, the avalanche photodiode is used. In the end of this work, due to the high power of the transmitting optical beam, the laser safety conditions are also discussed, including the deduced optical transmitters construction recommendations.
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|
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Modeling of the multichannel optical wireless link
Pavlů, Michal ; Fišer, Ondřej (referee) ; Poliak, Juraj (advisor)
This thesis deals with multi-channel wireless links with a higher range designated for free-space communications in an atmospheric media. Propagation of the optical beam in an atmosphere is analysed and various influences affecting the quality of the transmitted signal are described. The simulation is carried out for dual optical link. Link budget of individual paths working at the wavelengths in the atmospheric windows – 850 nm and 1550nm. It also examined optical intensity distribution of the transmitted beam. At the end of the work performed measurements and simulations verify the accuracy of the components used in wireless link.
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