Effect of adverse weather conditions and pointing error on the performance of 2-D WH/TS OCDMA over FSO link

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Bithi Mitra ◽  
Md. Jahedul Islam
Keyword(s):  
Free Space ◽  
Atmospheric Condition ◽  
Optical Power ◽  
Weather Conditions ◽  
Free Space Optical ◽  
Central Wavelength ◽  
Pointing Error ◽  
Adverse Weather ◽  
Code Division Multiple ◽  
Ber Performance

AbstractIn this paper, the performance of two-dimensional (2-D) wavelength-hopping/time-spreading (WH/TS) optical code division multiple access (OCDMA) system over free space optical (FSO) channel is analyzed in the presence of pointing error and different weather conditions. Prime code scheme is employed for both wavelength-hopping and time-spreading to address user code-matrix. The operating central wavelength of 1550 nm is considered to demonstrate the bit error rate (BER) performance of the proposed system as a function of various system parameters. The required optical power of the proposed system is determined to maintain a BER value of 10−9. The numerical evaluation interprets that the BER performance is highly dependent on transmission length, transmitted power, pointing error angle as well as the number of simultaneous user. It is also observed that the 2-D OCDMA system over free space needs minimum required optical power in case of rainy atmospheric condition, but it is maximum for foggy atmospheric condition.

Modelling of 10 Gbps Free Space Optics Communication Link Using Array of Receivers in Moderate and Harsh Weather Conditions

2017 ◽  
Vol 38 (3) ◽  
Author(s):  
Amit Gupta ◽  
Nagpal Shaina
Keyword(s):  
Free Space ◽  
Weather Conditions ◽  
Quality Data ◽  
Laser Source ◽  
Communication Link ◽  
Free Space Optical ◽  
Space Optics ◽  
Received Power ◽  
Adverse Weather ◽  
The Impact

AbstractIntersymbol interference and attenuation of signal are two major parameters affecting the quality of transmission in Free Space Optical (FSO) Communication link. In this paper, the impact of these parameters on FSO communication link is analysed for delivering high-quality data transmission. The performance of the link is investigated under the influence of amplifier in the link. The performance parameters of the link like minimum bit error rate, received signal power and Quality factor are examined by employing erbium-doped fibre amplifier in the link. The effects of amplifier are visualized with the amount of received power. Further, the link is simulated for moderate weather conditions at various attenuation levels on transmitted signal. Finally, the designed link is analysed in adverse weather conditions by using high-power laser source for optimum performance.

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>

Performance Evaluation of System in Free Space Optic Utilizing Gaussian Optical Filter in Different Detection Scheme

2019 ◽  
Vol 41 (1) ◽  
pp. 31-36
Author(s):  
H. Djellab ◽  
A. Bouarfa ◽  
S. Bojanic
Keyword(s):  
Wavelength Division Multiplexing ◽  
Free Space ◽  
Direct Detection ◽  
Optical Filter ◽  
Weather Conditions ◽  
Spectral Amplitude ◽  
Free Space Optical ◽  
Detection Scheme ◽  
High Data ◽  
Code Division Multiple

Abstract In recent years, free space optical communication (FSO) has become a leader for its unique characteristics: large bandwidth, unlicensed spectrum, simple implementation, low power and high data rate. However, we use as a transmission medium for Spectral Amplitude Coding-Optical Code Division Multiple Access SAC OCDMA system. In this paper, we investigate the optimum received power of FSO communication system employing SAC OCDMA, by using different detection technique, such us Spectral Direct Detection SDD and Single Photodiode Detection (SPD) technique under optical Gaussian filter decoder schemes with Modified Double Weight code (MDW). In this work, the adverse effects of atmospheric channel limit the possibility of a large FSO communication, moderate turbulence and hazy weather conditions are considered. The results show that the performance of the proposed system with wavelength-division-multiplexing (WDM) multiplexer (MUX) based on Gaussian optical filter with SDP detection fares better than the system employing SDD technique.

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.

Effect of Pointing Error on BER Performance of a Multi-wavelength OCDMA FSO System with SIK Dual Detector Receiver

2019 ◽  
Vol 40 (3) ◽  
pp. 247-253
Author(s):  
A. K. M. Nazrul Islam ◽  
S. P. Majumder
Keyword(s):  
Standard Deviation ◽  
Direct Detection ◽  
Code Length ◽  
Free Space Optical ◽  
Pointing Error ◽  
Multi Wavelength ◽  
Dual Detector ◽  
Multi Access ◽  
Code Division Multiple ◽  
Ber Performance

Abstract A novel analytical approach is presented to evaluate the bit error rate (BER) performance of a multi-wavelength optical code division multiple access (MW-OCDMA) free space optical (FSO) system using optical domain encoder and sequence inverse keying (SIK) balanced photodetector direct detection receiver taking the effect of pointing errors into considerations. The analysis is carried out to find the expression for the signal, multi-access interference (MAI) and crosstalk at the output of the SIK receiver in presence of pointing error. The BER performance results are evaluated for different values of standard deviation of pointing error, code length, number of simultaneous user and other system parameters. It is found that, MW-OCDMA system offers improved BER performance over single wavelength OCDMA FSO system. However, the performance of an MW-OCDMA system is degraded due to the effect of pointing error between the laser transmitter and optical receiver and the system suffers significant power penalty at a given BER of 10−9. The penalty is found to be 11.0 dB, 24.0 dB and 30 dB for jitter standard deviation of 1.3, 1.8 and 2.5 respectively when code length is 512 and number of user is 8 for number of wavelength 8. Further, the penalty can be greatly reduced by increasing the code length for a given number of user and number of wavelength.

Effect of different weather conditions on BER performance of single-channel free space optical links

Optik ◽  
2017 ◽  
Vol 137 ◽  
pp. 291-297 ◽  
Author(s):  
Mohamed H. Ibrahim ◽  
Heba A. Shaban ◽  
Moustafa H. Aly
Keyword(s):  
Free Space ◽  
Single Channel ◽  
Weather Conditions ◽  
Free Space Optical ◽  
Optical Links ◽  
Ber Performance

Estimating the Performance of Free Space Optical Link Under Adverse Weather Conditions by Using Various Models

2018 ◽  
Vol 103 (2) ◽  
pp. 1603-1613 ◽  
Author(s):  
Govardhani Immadi ◽  
M. Venkata Narayana ◽  
Sarat K. Kotamraju ◽  
A. Sree Madhuri
Keyword(s):  
Free Space ◽  
Weather Conditions ◽  
Free Space Optical ◽  
Optical Link ◽  
Adverse Weather Conditions ◽  
Adverse Weather

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