Hristo Ivanov

• Dr.techn. M.Sc.
• Graz University of Technology

This study emphasizes the importance of conducting a comprehensive analysis considering the Cn2 atmospheric parameter for a reliable assessment of the seeing value. It highlights the use of the ECMWF ERA5 model to simulate pressure, temperature, and humidity profiles, enabling the evaluation of optical degradation. Accurate modeling and monitoring...

Free Space Optics (FSO) technology enabling next-generation near-Earth communication is prone to severe propagation losses due to atmospheric-turbulence-induced fading and Mie scattering (clouds). As an alternative to the real-time evaluation of the weather effects over optical signal, a state-of-the-art laboratory testbed for verification of slant...

Optical wireless networks realized by means of gigabit optical wireless communication (OWC) systems are becoming, in a variety of applications, an important alternative, or a complementary solution, to their fiber-based counterparts. However, performance of the OWC systems can be considerably degraded in periods of unfavorable weather conditions, s...

Free space optics (FSO) is a wireless optical communication technology enabling extremely high data transmission rates, which can be used for a wide range of emerging applications. Nevertheless, FSO system reliability can be easily deteriorated in the presence of various weather-induced disruptions. The main two atmospheric effects influencing FSO...

Heavy rain, dense fog, snow, extreme temperatures and moving objects represent a few examples of environmental conditions, which have a significant influence on reliable communications over wireless networks. In particular, a wireless link is vulnerable to precipitation or to fluctuations caused by reflections of signals from moving objects. Wirele...

Various atmospheric effects have a negative influence on optical signals, especially in the troposphere, which must be taken into account in free space optical (FSO) communication systems. To obtain a quantitative estimate of these effects, different mathematical models are used, often based on empirical data from around the world. The main problem...

The significance of the multiple advantages of the terrestrial FSO links decreases due to fact that their performance depends strongly on the atmospheric conditions. A commonly used way to counterbalance the effects of such phenomena is the employment of hybrid systems, which are using both the optical wireless technology and the millimeter waves a...

This article presents simulation studies of elastic optical switching fabrics. Simulation experiments were conducted using the software developed by the authors. The simulator allows one to determine the loss probability for individual traffic classes offered to a single optical network node. The node architecture of elastic optical networks is bas...

Future ground to deep space communication systems should support Gbps data links, which are resilient to atmospheric impairments. An alternative and in the same time complementary to the conventional RF technology is the emerging deep space Free Space Optical (FSO) system, which can successfully face the challenge. Aligned with this future possibil...

Deep space Free Space Optical (FSO) systems are an emerging technology, characterized with very high performance in terms of information capacity and communication distances. However, this novel technology demands preliminary experiments, which are unmanageable in real conditions. Regarding this issue, an innovative approach for testing deep space...

Autonomous vehicles are sophisticated self-sufficient systems which employ hundreds of sensors. To improve road safety, the number of Advanced Driver Assistance Systems (ADAS) steadily increases. Consequently, the applied systems are growing in complexity and connectivity. The network architecture within vehicles, however, is only adapted and exten...

Performance of a deep space FSO-link incorporating SNSPD parametrized with deadtime, QE and N-array is addressed. Considering atmospheric turbulence fading ≤3.5 dB, data rate up to 20 Mbps for -17 (ph/ns)[dB] received signal is reached.

The article presents a description and operation principle of a simulator of elastic optical networks switching networks. The simulator allows to determine the loss probability for individual traffic classes offered to optical network nodes. The node architecture of elastic optical networks is based on the structure of the 3-stage Clos switching ne...