Kruse Model Research Articles

Investigative analysis of selected FSO models with varying wavelengths for tropical weather

In this paper, an investigation of some selected Mie and geometric Scattering models for free space optical (FSO) communication was done on available atmospheric data in Nigeria. The Kim and Kruse models have been established for the temperate region. In this work, the models were examined using the visibility data from the year 2008 to 2019. The models were examined under the 2% and 5% transmission threshold and under the wavelengths 780nm, 850nm, 1100nm, and 1550nm. The results indicates a higher attenuation at 780nm, supporting what is available in literature. The Suriza et al, ITU-R(Carbonneau) and Gailani et al  models were investigated using the rain intensity data. The Suriza et al model indicates a reduced attenuation compared to the other two models.

Software-based simulation to analyze the variation of digital modulation and atmospheric condition on the free space optic (FSO) link performance

Free Space Optic (FSO) is the solution for telecommunications technology that offers high data rates, wide bandwidth, and low power consumption. However, to maximize the performance of the FSO system, the modulation used should be considered in environmental conditions. This study aims to compare the performance of the FSO communication link based on digital modulation variations used in various weather conditions, including sunny, rainy, and foggy weather. This study uses two attenuation models, namely the Kim and Kruse models, with variations in transmission distance from 500 meters to 10 kilometers. Modulation variations used include QPSK, 8-PSK, 16-PSK, and 16-QAM at 10 Gbps bitrate. The simulation is accomplished using OptiSystem 17.0 software. The study results show that sunny weather (very clear) has the best visibility compared to rain and fog conditions with an attenuation value of 0.46 dB/km on the Kim and Kruse models. QPSK modulation has the best performance with a BER value of less than 1x10-12 up to a transmission distance of 8 km in sunny weather, 3 km in rainy weather (medium rain), and 800 m in foggy (moderate fog) weather. The 8-PSK modulation has a BER value of less than 1x10-12 with a range of 2000 m in sunny weather and 1500 m in rainy weather but does not meet the standards in foggy weather conditions. 16-PSK and 16-QAM modulation have above baseline BER values ​​during rainy and foggy conditions, but 16-QAM modulation still has a BER value of less than 1x10-3 during foggy conditions at a distance of 500 m.

Tropical Terrestrial Free Space Optical Link Performance Analysis

Free Space Optical (FSO) has a very good potential alternative solution to Radio Frequency (RF) to provide high terrestrial wireless communication. In tropical region, the only drawback of FSO is atmospheric attenuation due to mainly haze and rain. This study investigates the performance of FSO system over link distances that ranges between 9 km to 12 km as the average visibility in Kuala Lumpur, Malaysia is 10 km. Two models used to predict the atmospheric attenuation, namely Kruse model and modified Kruse model. These models are valid to predict the haze attenuation for visibilities that range between 9 to 12 km. The modified/corrected Kruse model shows some limitations in the prediction of haze attenuation over longer wavelength. However, the study indicates that attenuation due to haze is low, while air quality in Kuala Lumpur, Malaysia is acceptable. As the size of haze particles varies from 0.01 to 1 µm, the longer wavelength is preferable as 1550 nm to enhance FSO performance compared to 850 nm and 600 nm wavelengths. Thus, the longer wavelength is the optimal choice to enhance the FSO performance as it caused low scattering.

Performance analysis of FSO link under the effect of fog in Delhi region, India

Abstract Fog attenuation causes more loss than other weather conditions in a free space optics (FSO) link thus limiting the visibility distance. This work presents a detailed survey on the attenuation of the transmitted signal as a result of variation in visibility range caused by different fog conditions of the Delhi, Safdarjung region. Kim and Kruse models have been used to calculate attenuation as a result of fog conditions for three specific months (January, February and December) for seven consecutive years starting from 2013 to 2019. Received signal quality has been analyzed as a function of transmitted power, data rate, transmission range and operation wavelength. Descriptive statistical analysis of real time observed visibility data allows for the estimation of specific optical attenuation and enables in determining the link availability of the region for the complete year.

Performance analysis of FSO link under the effect of fog in Delhi region, India

Abstract Fog attenuation causes more loss than other weather conditions in a free space optics (FSO) link thus limiting the visibility distance. This work presents a detailed survey on the attenuation of the transmitted signal as a result of variation in visibility range caused by different fog conditions of the Delhi, Safdarjung region. Kim and Kruse models have been used to calculate attenuation as a result of fog conditions for three specific months (January, February and December) for seven consecutive years starting from 2013 to 2019. Received signal quality has been analyzed as a function of transmitted power, data rate, transmission range and operation wavelength. Descriptive statistical analysis of real time observed visibility data allows for the estimation of specific optical attenuation and enables in determining the link availability of the region for the complete year.

Fog and rain attenuation characterization and performance of terrestrial free space optical communication in Akure, Nigeria

Reliable broadband communication requires secure high data rate and bandwidth links. With the observedincrease in broadband users, known communication systems such as RF and microwave links cannot promise suchrequirements due to link interference and low bandwidth. A current communication system that promises suchrequirements and more is Free Space Optical (FSO) communication. This system basically involves the transmissionof signal-modulated optical radiation from a transmitter to a receiver through the atmosphere or outer space. However,location-variant atmospheric channel degrades the performance of an FSO system under severe atmosphericconditions, thus necessitating local atmospheric attenuation studies.This paper presents the characterization of both fog- and rain-induced attenuation and the performance ofan FSO system in a terrestrial terrain at Akure, Nigeria. One-year archived visibility data and in-situ measured 1-minute integration time rain rate data obtained from Nigerian Meteorological Agency (NIMET) and the Departmentof Physics, Federal University of Technology, Akure were used to compute the fog- and rain-induced specificattenuations using Kruse model and Carboneur model respectively. The performance of the FSO system is analyzedthrough link margin by using the parameters of a commercial optical transceiver, Terescope 5000.

Fog and Rain Attenuation Characterization and Performance of Terrestrial Free Space Optical Communication in Akure, Nigeria

Reliable broadband communication requires secure high data rate and bandwidth links. With the observed increase in broadband users, known communication systems such as RF and microwave links cannot promise such requirements due to link interference and low bandwidth. A current communication system that promises such requirements and more is Free Space Optical (FSO) communication. This system basically involves the transmission of signal-modulated optical radiation from a transmitter to a receiver through the atmosphere or outer space. However, location-variant atmospheric channel degrades the performance of an FSO system under severe atmospheric conditions, thus necessitating local atmospheric attenuation studies. This paper presents the characterization of both fog- and rain-induced attenuation and the performance of an FSO system in a terrestrial terrain at Akure, Nigeria. One-year archived visibility data and in-situ measured 1-minute integration time rain rate data obtained from Nigerian Meteorological Agency (NIMET) and the Department of Physics, Federal University of Technology, Akure were used to compute the fog- and rain-induced specific attenuations using Kruse model and Carboneur model respectively. The performance of the FSO system is analyzed through link margin by using the parameters of a commercial optical transceiver, Terescope 5000.

A laboratory experimental study on laser attenuations by dust/sand storms

In this paper, the laser beam attenuation by sand/dust storms is experimentally investigated under controlled lab conditions for 5 laser wavelengths, i.e., 405 nm and 532 nm in visible band and 850 nm, 1064 nm and 1550 nm in near infrared band. It is found that the attenuation coefficient of the laser links exponentially decreased with the increase of the visibility of dust/sand storms mimicked in a glass chamber with mixed-size sand samples. The longer the laser wavelength, the lower the attenuation coefficient under the same visibility, e.g., when the visible range is 0.1 km, 0.5 km and 1 km, the attenuation coefficient of the laser links with the wavelength 405 nm is 174 ± 10.9 dB/km, 33.7 ± 4.7 dB/km and 17.7 ± 1.6 dB/km, while the attenuation coefficient of the laser links with the wavelength 1550 nm is 126 ± 10.7 dB/km, 23.7 ± 10.8 dB/km and 9.6 ± 2.5 dB/km, respectively. In addition, it is found that the attenuation decreases with increasing effective particle size under a given visibility. Furthermore, based on the experimental results and Kruse model, an improved model for the calculation of laser beam attenuation by sand/dust storms, which is a function of both laser wavelength and effective particle size of the sand/dust storms, is proposed.

Quantum cascade lasers and the Kruse model in free space optical communication

Mid-infrared (MIR) free space optical communication has seen renewed interest in recent years due to advances in quantum cascade lasers. We present data from a multi-wavelength test-bed operated in the New York metropolitan area under realistic weather conditions. We show that a mid-infrared source (8.1 microm) provides enhanced link stability with 2x to 3x greater transmission over near infrared wavelengths (1.3 microm & 1.5 microm) during fog formation and up to 10x after a short scavenging rain event where fog developed and visibility reduced to approximately 1 km. We attribute the improvement to less Mie scattering at longer wavelengths. We confirm that this result is generally consistent with the empirical benchmark Kruse model at visibilities above 2.5 km, but towards the 1 km eye-seeing limit we measured the equivalent MIR visibility to be > 10 km.