scholarly journals Availability Prediction Methods for Terrestrial Free-Space-Optical Link Under Tropical Climate

2018 ◽  
Vol 10 (1) ◽  
pp. 224
Author(s):  
Ahmed Basahel ◽  
Md Rafiqul Islam ◽  
Mohamed Habaebi ◽  
Suriza Ahmad
Keyword(s):  
Free Space ◽  
High Speed ◽  
Weather Conditions ◽  
Tropical Climate ◽  
Prediction Methods ◽  
Free Space Optical ◽  
Tropical Regions ◽  
Link Distance ◽  
Link Budget ◽  
Point To Point

<p>Free-space optical (FSO) links provide high speed point-to-point wireless communication, but its availability can easily be affected by weather conditions. In heavy rainfall regions, FSO links are relatively sensitive to rain. Availability prediction of FSO is indispensable part, especially in tropical areas. In this paper, methods to predict FSO link availability are presented. The overall performance of FSO link is described in terms of the availability that can be achieved over anticipated link distance. The availability prediction methods demonstrated for an FSO link ranges up to 5 km. The availability prediction methods are based on long-term statistics of atmospheric attenuations and FSO link budget under tropical climate condition. In tropical regions, for a terrestrial FSO link, carrier class availability can be achieved over a few hundred meters only; whereas enterprise class availability can be achieved over a few kilometers link distances. </p>

scholarly journals Impact of pointing error on SISO/MISO drones swarm-based free space optical system in weak turbulence regime

2021 ◽  
Vol 23 (2) ◽  
pp. 918
Author(s):  
Abdullah Jameel Mahdi ◽  
Wamidh Jalil Mazher ◽  
Osman Nuri Ucan
Keyword(s):  
Free Space ◽  
Communication Systems ◽  
High Performance ◽  
Signal To Noise Ratio ◽  
Weather Conditions ◽  
Free Space Optical ◽  
Single Input Single Output ◽  
Pointing Error ◽  
Single Output ◽  
Link Distance

<p>Applying the drone-based free space optical (FSO) technology is recent in communication systems. The FSO technology hashigh-security features dueto narrow beamwidth, insusceptible to interferences, free license and landline connection is not appropriate. However, these advantages face many obstacles that affect the system's performance, such as random weather conditions and misalignment. The pointing error Hpis one of the critical factors of the channel gain H. The related parameters of the Hp factor: the pointing error angles θr and the path length Z, were manipulated to extract the applicable values at various receiver diameter values. The proposed system has two topologies: single input single output (SISO) and multiple input single output (MISO), flying in weak atmospheric turbulence. The simulation was done using MATLAB software 2020. The average bit error rate (ABER) for the system versus signal-to-noise ratio (SNR) were verified and analyzed. The results showed that at θr=10<sup>−3</sup>rad, Z increased in the range 10~100m for each one-centimeter increase of DR. At θr=10<sup>−2</sup>rad, the applicable Z was nearly 10% of the link distance Z when θr=10<sup>−3</sup>rad was applied. Consequently, an increase in θr must correspond decrease in Z and vice versa to maintain the system at high performance.</p>

scholarly journals A space division multiplexed free-space-optical communication system that can auto-locate and fully self align with a remote transceiver

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Mojtaba Mansour Abadi ◽  
Mitchell A. Cox ◽  
Rakan E. Alsaigh ◽  
Shaun Viola ◽  
Andrew Forbes ◽  
...  
Keyword(s):  
Rural Communities ◽  
Free Space ◽  
High Speed ◽  
Low Complexity ◽  
Mesh Network ◽  
Alignment Algorithm ◽  
Free Space Optical ◽  
Space Optical Communication ◽  
Point To Point ◽  
Electrical Components

AbstractFree-Space Optical (FSO) systems offer the ability to distribute high speed digital links into remote and rural communities where terrain, installation cost or infrastructure security pose critical hurdles to deployment. A challenge in any point-to-point FSO system is initiating and maintaining optical alignment from the sender to the receiver. In this paper we propose and demonstrate a low-complexity self-aligning FSO prototype that can completely self-align with no requirement for initial manual positioning and could therefore form the opto-mechanical basis for a mesh network of optical transceivers. The prototype utilises off-the-shelf consumer electrical components and a bespoke alignment algorithm. We demonstrate an eight fibre spatially multiplexed link with a loss of 15 dB over 210 m.

Performance analysis of free space optical system incorporating circular polarization shift keying and mode division multiplexing

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Meenu ◽  
Anshu Sharma ◽  
Rahul Malhotra
Keyword(s):  
Circular Polarization ◽  
Free Space ◽  
Heavy Rain ◽  
Weather Conditions ◽  
Detailed Comparison ◽  
Free Space Optical ◽  
Light Rain ◽  
Link Distance ◽  
Mode Division Multiplexing ◽  
Shift Keying

Abstract In this work, a free-space optical (FSO) communication system with the integration of mode division multiplexing and circular polarization shift keying (CpolSK) is proposed at 2 × 40 Gbps using LG00 and LG01 modes. Effects of diverse weather conditions such as clear weather, light rain, moderate rain, heavy rain, thin fog, thick fog, and heavy fog are studied on system performance. Further, a detailed comparison of CpolSK and polarization shift keying (PolSK) is performed at different FSO lengths in terms of log bit error rate. For implementation, analysis, and comparison, Optiwave Optisystem software is used and results show that CpolSK covers 100 km link distance and PolSK limits to 90 km only. Also, LG00 mode performs better than LG01 mode under all weather instabilities in the proposed system.

scholarly journals Hybrid MDM-PDM Based Ro-FSO System for Broadband Services by Incorporating Donut Modes Under Diverse Weather Conditions

2021 ◽  
Vol 9 ◽  
Author(s):  
Sushank Chaudhary ◽  
Lunchakorn Wuttisittikulkij ◽  
Jamel Nebhen ◽  
Xuan Tang ◽  
Muhammad Saadi ◽  
...  
Keyword(s):  
Free Space ◽  
High Speed ◽  
Weather Conditions ◽  
Sensor Data ◽  
Electromagnetic Spectrum ◽  
Free Space Optical ◽  
Adverse Weather ◽  
Dense Fog ◽  
High Speed Data ◽  
Clear Weather

High-speed data demand in sensitive locations has prompted new wireless technologies to grow in areas like hospitals for bio-sensor data transmission between doctors and patients. However, interference of electromagnetic spectrum or highly sensitive medical equipment in such locations can prevent radio waves which can further compromise the health of patients. Radio over Free Space Optics (Ro-FSO) can fulfil high-speed data demand in such locations without any such interference. However, the Ro-FSO performance is highly influenced by different adverse weather conditions, particularly haze and rainfall, which further cause attenuation in the transmission path of Ro-FSO systems. These atmospheric turbulences mainly affect the transmission link range of Ro-FSO systems. In this work, Ro-FSO system is designed by incorporating hybrid mode division multiplexing (MDM) and polarization division multiplexing (PDM) schemes to deliver four independent channels, each carrying 10 Gbps data upconverted to 40 GHz radio signal, over 3.4 km free space optical link operating under clear weather conditions. In addition to this, the proposed Ro-FSO link is subjected to different weather conditions, particularly partially hazy/rainy and dense fog/very rainy. The reported results indicate the achievement of acceptable bit error rate (BER≈10–3) for all channels up to 3400m FSO link under clear weather conditions, 1000m under partially haze/rain and 620 m under dense fog/heavy rain.

scholarly journals Effect of Environmental Parameters on the Performance of Optical Wireless Communications

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Hosam Abd Elrazek Mohamed Ali ◽  
El-Sayed Soliman A. Said ◽  
Mohamed Ebrahim Yousef
Keyword(s):  
Wireless Communications ◽  
Free Space ◽  
Communication Systems ◽  
High Speed ◽  
System Analysis ◽  
Environmental Parameters ◽  
Weather Conditions ◽  
Optical Wireless ◽  
Free Space Optical ◽  
Optical Wireless Communications

Free space optical communication systems are the future of the communication systems which can meet the needs of the end users who are demanding high bandwidths to support high-speed communication. These merits are due to its numerous advantages as well as their better performance. This paper studies the effect of environmental parameters like rain, fog, haze, snow, and dust on the performance of optical wireless communications using Opti-system program. This work considers the effect of visibility as well as operating wavelengths on atmospheric attenuation in different weather conditions for free space optical link. For different weather conditions the max distance between transmitter and receiver can also be estimated. The system analysis depicted the better performance of the Multi-Input/Multi-Output (MIMO) configurations compared to Single Input/Single Output (SISO) at different weather conditions.

Erbium/Ytterbium-Doped Waveguide Amplifier (EYDWA) for extended reach of Wavelength Division Multiplexing based free space optics system (WDM/FSO)

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Bentahar Attaouia ◽  
Kandouci Malika ◽  
Ghouali Samir
Keyword(s):  
Wavelength Division Multiplexing ◽  
Free Space ◽  
Cost Effective ◽  
Weather Conditions ◽  
Free Space Optical ◽  
Wavelength Division ◽  
Space Optics ◽  
Effective Implementation ◽  
Transmission Distance ◽  
The Cost

AbstractThis work is focused to carry out the investigation of wavelength division multiplexing (WDM) approach on free space optical (FSO) transmission systems using Erbium Ytterbium Doped Waveguide Amplifier (EYDWA) integrated as post-or pre-amplifier for extending the reach to 30 Km for the cost-effective implementation of FSO system considering weather conditions. Furthermore, the performance of proposed FSO-wavelength division multiplexing (WDM) system is also evaluated on the effect of varying the FSO range and results are reported in terms of Q factor, BER, and eye diagrams. It has been found that, under clear rain the post-amplification was performed and was able to reach transmission distance over 27 Km, whereas, the FSO distance has been limited at 19.5 Km by using pre-amplification.

Sign in / Sign up

Export Citation Format

Share Document