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The paper presents an experimental testbed, which will be used for the demonstration of more than 1 Tbps free-space optical (FSO) transmission in a scenario similar to that of GEO uplink. The chosen terrestrial scenario corresponds to worst-case conditions of a GEO uplink scenario according to the atmospheric channel characteristics and the geometry of the scenario. The testbed consists of a DWDM-based...
The paper deals with the terrestrial optical wireless links (TOWL) operating with coherent laser beams. The contribution discusses two main types of TOWL: data link and test link. Main aspects of constructions are shown. Purely photonic concept of given links is presented and justified. For the TOWL, applications not only in the field of communications, but also in environmental informatics or for...
Nowadays FSO (Free Space Optics) also called Optical Wireless, is a well-established technology for closing the last mile gap. Optical Wireless is best suited to be directly connected to fibre optics, like the extension of a fibre cable for access networks. But also combinations with RF- and wireless networks are of main interest in current applications. Various technologies have different influences...
The paper summarises basic principles of free-space optical (FSO) links and their applications. Further an experimental FSO platform is presented. Its main purpose is to demonstrate FSO benefits for last-mile interconnect solution, especially for end users. The realized FSO link transceiver based on FPGA is described in detail, including its expected performance characteristics. The main benefit of...
In the paper, an optical wireless link for point-to-point communication is analyzed. Its main focus is the analysis of the influence of various misalignments on the received power. Analysis includes influence of the tilt of the transmitter and the receiver as well as their mutual misalignment respecting the Gaussian intensity distribution of the transmitted beam in terms of geometrical optics. As...
This paper deals with multi-channel wireless links with a higher range designated for free-space optical (FSO) communications in an atmospheric media. Propagation of the optical beam in the atmosphere is analyzed and a novel approach of the photonic transmitter was proposed and analyzed.
In this work, a free space optical (FSO) link for the ground-to-train communications is proposed. Analytical analysis is carried out for the case of the straight track as well as curved rail tracks. We show that the transmitter divergence angle, the transmit power and the size of the concentration lens needs to increase for the curved section of the rail track compared to the straight track. We derive...
The influence of wind on FSO link attenuation at the experimental observatory of the Institute of Atmospheric Physics Prague on the Milesovka hill has been studied for last three and half years (1. 2009 – 8. 2012). New sophisticated database of all measured data (relevant meteorological parameters and FSO link attenuation data) in Matlab data format has been completed for simpler utilization concerning...
Examining the functioning of sensors for measuring pressure shows that most of them make we of a displacement. The linearity and the sensitivity of this type of sensor are closely dependent on the value of this displacement. For the sake of linearity and repeatabiity of large, signals, the displacement has to be small Consequently the output signals obtained are weak.
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