Space Optics Research Articles

Modelling System Parameters for Improvised Performance in Free Space Optics (FSO) Networks

Free space optics (FSO) is a remote method for correspondence that send information by means of an optical source. The medium among transmitter and recipient is a free space that has an away from of sight for imparting the sign. Air, vacuum, and space can go about as free space. Establishment of this framework is financially savvy contrasted with different frameworks and can be set up with in less time. The upside of this framework is it can send a lot of information because of high transmission capacity. A portion of the components which influence the transmission of FSO are downpour, mist, fog and actual obstacles. Two FSO joins are planned in this paper one with a variety of laser and one with a solitary laser, we are going to investigation the Max. Q along with the Bit error rate esteem for the two frameworks at various constrictions. Multiplexing of the signals is carried out to estimate the performance of the system. Due to the use of multiplexing high bit rates are achieved. The link distance under consideration for this experimental simulation was at 10 km which includes various power levels of the laser. Performance of the two links is compared in the results with the parameter of BER at various power levels by using BER analyzer.

Intelligent transportation system using wireless optical communication: a comparative study

Intelligent Transportation Systems (ITSs) are being proposed, examined, and applied to enhance road safety and traffic efficiency. However, the automotive industry has stringent criteria for safety applications that demand connections that are dependable and have low latency, and high data rates. In this paper, it is widely agreed that both Visible Light Communication (VLC) and Free Space Optics (FSO) represent promising solutions, because of their complementary advantages compared to Radio Frequency (RF). VLC technology is chosen in ITS overall other optical wireless systems primarily due to its low cost and lack of licensing or new infrastructure requirements. Hence, a comparative study is applied between standalone VLC system, and a hybrid FSO/VLC system in term of Bit Error Rate (BER), coverage distance, and Signal to Noise Ratio (SNR). The VLC/FSO system provides a reliable communication link over a long distance (900 m) compared to VLC standalone system with 10−6 BER and acceptable SNR of ∼\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\sim$$\\end{document} 25 dB.

Coevolution and Nuclear Structure in the Dwarf Galaxy POX 52 Studied by Multiwavelength Data from Radio to X-Ray

The nearby dwarf galaxy POX 52 at z = 0.021 hosts an active galactic nucleus (AGN) with a black hole (BH) mass of M BH ∼ 105–6 M ⊙ and an Eddington ratio of ∼0.1–1. This object provides the rare opportunity to study both AGN and host-galaxy properties in a low-mass highly accreting system. To do so, we collected its multiwavelength data from X-ray to radio. First, we construct a spectral energy distribution, and by fitting it with AGN and host-galaxy components, we constrain AGN-disk and dust-torus components. Then, while considering the AGN-disk emission, we decompose optical Hubble Space Telescope images. As a result, it is found that a classical bulge component is probably present, and its mass (M bulge) is consistent with an expected value from a local relation. Lastly, we analyze new quasi-simultaneous X-ray (0.2–30 keV) data obtained by the Nuclear Spectroscopic Telescope Array and XMM-Newton. The X-ray spectrum can be reproduced by multicolor blackbody, warm and hot coronae, and disk and torus reflection components. Based on this, the spin is estimated to be a spin = 0.998−0.814, which could suggest that most of the current BH mass was achieved by prolonged mass accretion. Given the presence of the bulge, POX 52 would have undergone a galaxy merger, while the M BH–M bulge relation and the inferred prolonged accretion could suggest that AGN feedback occurred. Regarding the AGN structure, the spectral slope of the hot corona, its relative strength to the bolometric emission, and the torus structure are found to be consistent with Eddington-ratio dependencies found for nearby AGNs.

Performance analysis of 160 Gbps-60 GHz OFDM-MIMO RoFSO transmission with WDM-PDM dual multiplexing

Abstract An orthogonal frequency division multiplexed-radio over free space optics (OFDM-RoFSO) communication system with dual multiplexing is proposed. Eight input data streams are transmitted simultaneously by using wavelength division multiplexing (WDM) at level 1 and polarization division multiplexing (PDM) at level 2. Input data streams 1–4 and 5–8 are assigned with same set of carrier frequencies i.e. 193.1 THz, 193.3 THz, 193.5 THz and 193.7 THz and separate polarization levels (X and Y polarized) before transmitting through RoFSO link. A total data rate of 160 Gbps (4 × 2 × 20 Gbps) is achieved in this design. With proposed system, channel performance is evaluated under the influence of atmospheric attenuation and turbulence conditions while measuring system BER, Q-factor, SNR and received power etc. The effect of channel crosstalk is analysed for WDM-PDM dual multiplexed design while considering single input single output (SISO) and multiple input multiple output (MIMO) FSO configurations. The overall analysis predicts that a higher transmission rate and improved capacity levels can easily be achieved with dual multiplexed system.

Range augmentation of 16 × 60 GHz WDM RoFSO system in foggy & rainy weather

Abstract The wavelength division multiplexed radio over free space optics (WDM RoFSO) system is a paramount candidate to provide extended range thus enabling efficient last mile connectivity. But the conventional design is unable to transmit the information up to larger distances under harsh climate conditions. An improved 16 channel WDM-RoFSO system is proposed and simulated which yields quality transmission for extended range under the attenuation of 5.8 dB/km, 7.7 dB/km, 9.2 dB/km and 26 dB/km for foggy and rainy conditions respectively. A radio frequency (RF) signal of 60 GHz is modulated over an optical signal carrier and successfully transported with cumulative 16 × 10 Gbps bit rate up to 3.75 km in foggy environment. The link range is augmented by 1.65 km, 0.9 km, 1.8 km & 1 km for light fog, moderate fog, moderate rainfall and heavy rainfall conditions respectively.

Enhancing high-speed networks using RGB-based WLAN through Ro-FSO integration in the 5 GHz band

Abstract The limited bandwidth constraints imposed by conventional wireless carriers pose a significant hurdle when it comes to the delivery of high-speed broadband services. In response to this challenge, Radio over Free Space Optics (Ro-FSO) has emerged as a viable and innovative solution, seamlessly amalgamating wireless and optical systems. This integration proves particularly invaluable in sensitive environments, such as hospitals, where the risk of electromagnetic interference disrupting critical medical equipment is a real concern. Ro-FSO offers a disruption-free avenue for high-speed data transmission, positioning it as the ideal choice for broadband services, including Wireless Local Area Networks (WLANs). Within the scope of this study, we introduce a high-speed Ro-FSO link, showcasing the capability to concurrently transmit three independent channels with Red, Green and Blue (RGB) laser respectively, each supporting a robust 1 Gbps data rate. These data streams are skilfully up-converted to the 5 GHz RF bands, encompassing transmission distances of 650 m across the FSO channel. Our numerical simulation findings underscore the successful transmission of all the channels using wavelength division multiplexing (WDM), seamlessly meeting the prescribed Bit Error Rate (BER) and eye pattern criteria, solidifying the Ro-FSO’s standing as a promising solution for high-speed broadband delivery.

Hybrid RoF-RoFSO system for broadband services by incorporating polarization division multiplexing scheme

Abstract The limited bandwidth of traditional wireless carriers presents a challenge for delivering high-speed broadband services. To address this, radio-over-free space optics (Ro-FSO) emerges as a viable solution, seamlessly integrating wireless and optical systems. This integration is particularly valuable in sensitive environments such as hospitals, where electromagnetic interference can disrupt medical equipment. Ro-FSO provides interference-free high-speed data transmission, making it an ideal choice for broadband services, including WLANs. This study presents a high-speed Ro-FSO link capable of simultaneously transmitting two independent channels, each carrying 1 Gbps data up-converted to the 2.4 GHz and 5 GHz RF bands over a 5 km SMF and 4200 m FSO channel. The incorporation of polarization division multiplexing enhances the spectral efficiency of the Ro-FSO link. Our findings demonstrate the successful transmission of both channels meeting the required bit error rate (BER) and eye pattern criteria.

Intelligent-reflecting-surfaces-assisted hybrid FSO/RF communication with diversity combining: a performance analysis

Free space optics (FSO) and radio frequency (RF) communication systems exhibit complementary characteristics, with FSO being susceptible to fog, turbulence, and pointing errors, whereas RF is susceptible to rain and small scale fading. These inherent complementary characteristics between FSO and RF communication systems enable the hybrid configuration to effectively alleviate the impact of environmental impediments. This paper presents the performance analysis of an intelligent reflecting surfaces (IRSs)-assisted hybrid FSO/RF system under atmospheric turbulence (AT), pointing errors (PE), small scale fading effects, and attenuation due to climatic conditions such as fog, rain, etc. To characterize the AT, gamma–gamma distribution is used, and the multipath fading in the RF link is modeled using Nakagami-m distribution. At the receiver, signals from both the FSO and RF links are combined using either the selection combining (SC) or maximal-ratio combining (MRC) technique. We derive the exact closed-form expressions for outage probability and average symbol error rate (ASER) for both diversity combining schemes. The proposed system is compared with the direct link (DL) FSO system, IRSs-assisted FSO system, and hybrid FSO/RF system with diversity combining schemes. Further, the performance comparison between the SC and MRC schemes is also reported. Finally, the accuracy of the analytical expressions is verified by utilizing Monte Carlo simulations.

Early-time Ultraviolet and Optical Hubble Space Telescope Spectroscopy of the Type II Supernova 2022wsp

We report early-time ultraviolet (UV) and optical spectroscopy of the young, nearby Type II supernova (SN) 2022wsp obtained by the Hubble Space Telescope (HST)/STIS at about 10 and 20 days after the explosion. The SN 2022wsp UV spectra are compared to those of other well-observed Type II/IIP SNe, including the recently studied Type IIP SN 2021yja. Both SNe exhibit rapid cooling and similar evolution during early phases, indicating a common behavior among SNe II. Radiative-transfer modeling of the spectra of SN 2022wsp with the TARDIS code indicates a steep radial density profile in the outer layer of the ejecta, a solar metallicity, and a relatively high total extinction of E(B − V) = 0.35 mag. The early-time evolution of the photospheric velocity and temperature derived from the modeling agree with the behavior observed from other previously studied cases. The strong suppression of hydrogen Balmer lines in the spectra suggests interaction with a preexisting circumstellar environment could be occurring at early times. In the SN 2022wsp spectra, the absorption component of the Mg ii P Cygni profile displays a double-trough feature on day +10 that disappears by day +20. The shape is well reproduced by the model without fine-tuning the parameters, suggesting that the secondary blueward dip is a metal transition that originates in the SN ejecta.

Performance Analysis of Multi-Hop Hybrid FSO/mm Wave Communication System for Next-Generation Wireless Networks

Next-generation wireless networks are facing increasing demand for high data rates, low latency, and seamless connectivity. To address these challenges, a multi-hop hybrid communication system integrating Free Space Optics (FSO) and millimeter wave (mm Wave) technologies for backhaul communication is proposed. This system combines the advantages of FSO, such as high bandwidth and low latency, with the robustness and reliability of mm Wave technology. The multi-hop architecture enables the formation of a network of interconnected nodes, providing improved coverage and flexibility. Each node is equipped with FSO and mm Wave transceivers, allowing for seamless handovers and adaptive routing. For the proposed system, analytical formulas for outage probability (OP) and average bit error rate (ABER) are derived and validated using simulations. The Monte Carlo simulations provide evidence of enhanced performance in the proposed Multi-Hop Hybrid FSO/mm Wave (MHFM) system compared to the FSO system.

An All-Digital Optical Phase-Locked Loop Suitable for Satellite Downlinks

The optical signal propagation used in satellite uplinks and downlinks is influenced by absorption, scattering, and changes in the atmospheric refractive index or turbulence, causing optical signal attenuation. A free space optics (FSO) communications system using coherent communication can improve the link sensitivity and reach higher distances. This article proposes a new architecture for the phase detector in an all-digital optical phase-locked loop (OPLL) for coherent optical detection. Firstly, the performance of the proposed phase detector is evaluated under Gaussian noise, where the best operation point is found for the OPLL working with two sample rates: 625 MSa/s and 10 GSa/s. The system analyses also take a non-negligible delay into account. Then, it will be evaluated and compared with an OPLL using an analog phase detector in the presence of atmospheric turbulence. Finally, in three different atmospheric turbulence conditions, the effect of wind speed on communication quality is investigated through the obtained bit error rate (BER) from the recovered data for a bit rate of 20 Gbps. The results show that the proposed digital phase detector can track a signal under longer feedback loop delays and fading signals.

The Use of POCUS-Obtained Optic Nerve Sheath Diameter in Intracerebral Hemorrhage

Background: Intracerebral hemorrhage (ICH) is associated with high morbidity and mortality. ICH causes increased intracranial pressure (ICP), leading to brain herniation as the disease progresses. Neurological physical exam and monitoring of the disease progression can be challenging due to the impaired consciousness and routine clinical management in this patient population. Given the continuity of the intracranial cavity with the optic nerve subarachnoid space, an increased ICH leads to distension of the optic nerve sheath. We herein examined the correlation between the ICH volume and the optic nerve sheath diameter (ONSD) measured by point of care ultrasound (POCUS). Methods: Patients with ICH diagnosed with a head computed tomography (CT) scan were prospectively enrolled in this study. A portable ultrasound was used to measure the (ONSD); the volume of ICH hematoma, the Acute Physiology And Chronic Health Evaluation IV score, and the Intracerebral Hemorrhage score were collected. A Spearman rank correlation coefficient test was used to assess the relationship between continuous variables. A Wilcoxon rank sum test was used to assess differences in continuous variables between two groups. A p-value less than 0.05 was deemed as statistically significant. Results: A total of 28 subjects were enrolled. A moderate positive correlation was detected between hemorrhage volume and the average ONSD (correlation = 0.4214, p = 0.0255). A weak positive correlation was detected between average ONSD and APACHE IV (correlation = 0.2347, p = 0.2294). A weak moderate positive correlation was detected between average ONSD and ICH score (correlation = 0.1160, p = 0.5566). Conclusions: In this study we demonstrate that ONSD is moderately correlated with hematoma size. A potential application may include serial measurements of the ONSD with ultrasound. This may offer a quick, non-invasive technique that can be used in an intracerebral hemorrhage to monitor the stability or expansion of a hematoma indirectly, and potentially catch a catastrophic event like cerebral herniation.

Efficient Encoding Method for Combined Codes in the MWD Telemetry System

MPPM (Multipulse Position Modulation) is a pulse code technology that is widely used in optical communication and deep space communication due to its high energy efficiency. Combination code is a variation of MPPM and is widely used in MWD (Measurement While Drilling) telemetry systems. However, whether it is MPPM or combination code, it is difficult to establish a simple mapping relationship between bit symbols and pulse symbols. Therefore, an encoding table is usually used to realize the mapping between bit symbols and pulse symbols. With an increase in bit width, the storage complexity of the encoding table increases exponentially. This is unacceptable for underground transmitters working in harsh environments. This paper maps the code symbols of MPPM to a hyper-triangular region of a high-dimensional tensor and establishes a simple lookup table and lookup algorithm to achieve low-complexity mapping from bit symbols to MPPM code symbols. At the same time, this paper also provides a method for extending from MPPM code symbols to commonly used combination code symbols in MWD, thereby providing an efficient implementation path for large bit width combination code encoding at the underground end of MWD.

Metafiber transforming arbitrarily structured light

Structured light has proven useful for numerous photonic applications. However, the current use of structured light in optical fiber science and technology is severely limited by mode mixing or by the lack of optical elements that can be integrated onto fiber end-faces for wavefront engineering, and hence generation of structured light is still handled outside the fiber via bulky optics in free space. We report a metafiber platform capable of creating arbitrarily structured light on the hybrid-order Poincaré sphere. Polymeric metasurfaces, with unleashed height degree of freedom and a greatly expanded 3D meta-atom library, were 3D laser nanoprinted and interfaced with polarization-maintaining single-mode fibers. Multiple metasurfaces were interfaced on the fiber end-faces, transforming the fiber output into different structured-light fields, including cylindrical vector beams, circularly polarized vortex beams, and arbitrary vector field. Our work provides a paradigm for advancing optical fiber science and technology towards fiber-integrated light shaping, which may find important applications in fiber communications, fiber lasers and sensors, endoscopic imaging, fiber lithography, and lab-on-fiber technology.

Calculations of Particle Bombardment Due to Dust and Charged Particles in the ISM on the Project Starshot Gram-Scale Interstellar Probe

The Breakthrough Initiatives Project Starshot proposes to send a gram-scale laser driven spacecraft to the Alpha Centauri system in a 20 year mission travelling at v~0.2c. One of the challenges of this mission as the spacecraft moves through the interstellar medium is the presence of dust and gas (mostly hydrogen). The dust has a typical matter-density of 2.57 × 10-27 g/cm3 with typical particle mass being 3 × 10-13 g although some of the largest particles may be 5 × 10-9 g in mass. These dust particles will deposit ~1012-1016 MeV onto the spacecraft with an energy flux of order ~0.3 J/sm2. We consider the erosion of the spacecraft frontal area due to dust and also heating effects. We attempt to characterise the likely environment for the Starshot mission and estimate the particle bombardment shielding requirements in terms of mass and thickness of material. Current analysis estimates that the likely erosion rates are of order ~10-11-10-8 g/s and that the frontal area temperature for the models examined in this paper will be ~135.2 K depending on the ratio of frontal area to radiating area. For an assumed shielding material with atomic number range 3-13 (Lithium to Aluminium), and for spacecraft geometries with radii ~1 mm and cylindrical length ~5 mm, over a 21.5 year mission duration, this would suggest a shielding thickness of ~1.4-3 mm. This would also suggest a shielding mass in the range ~0.01-0.05 g; depending on the material choice, spacecraft size and chosen geometry. This would represent between ~1–5% of the total mass, assuming a spacecraft mass of 1g (driven by a ~102 GW laser power). We also examine the additional effects of charged particles and estimate the stopping power and penetration range for different materials. Finally, we briefly examine the potential to use the incoming energy flux as a power source for the transmission of an optical laser deep space communication system. The work presented highlights the close coupling in the Project Starshot spacecraft design between the vehicle geometry and the particle bombardment requirements.

Development of a cost-effective optical network based on free space optical (FSO) and optical fiber links for enabling smart city infrastructure: A hybrid approach

Due to the gigantic rise in the use of high data rate-based applications and the ongoing transformation of Indian cities into smart cities, there is a need for a high-speed communication framework to handle the enormous data traffic. The radio frequency (RF) and microwave links seem to be incapable of offering sufficient bandwidth required by the data-hungry applications and consequently, the need for a more effective solution for tackling the issue of scarcity of bandwidth resources has become the necessity of current network infrastructure in India. In this study, a hybrid optical fiber-free space optical (OF-FSO) system for offering high-speed data services has been proposed to assist the implementation of smart city infrastructure in India. This study aims to inspect the system performance of the proposed model under the climatic conditions of mountainous, desert, flatland, and seaside regions of India. The proposed hybrid OF-FSO system comprises a fixed single-mode fiber (SMF) of 20 km and an FSO link (having a varied transmission range between 0–2 km). The proposed hybrid model can support an FSO link of 1.72 km for a fixed SMF of 20 km, corresponding to a bit error rate of the order of 10−4 for atmospheric conditions of the seaside location of Chennai and the range of FSO link varies from 1.32 km to 1.57 km for other locations of India, for the same length of SMF and bit error rate. Furthermore, the proposed hybrid OF-FSO has demonstrated a reduction of 30.8% in Capital Expenditure (CAPEX) cost in contrast to the conventional passive optical network (PON) system.

Wheel‐based 5G fronthaul/backhaul hybrid MDM‐NGPON/FSO system under Gamma‐Gamma turbulence and weather effects

SummaryThis work presents the bidirectional and symmetric 40 Gbps wheel architecture comprising 16 channels‐based bidirectional hybrid next generation passive optical network with free space optics (NGPON/FSO) system using mode division multiplexing (MDM) scheme. The system incorporates a low‐cost high bandwidth and integrated time and wavelength division multiplexing with orthogonal frequency division multiplexing (TWDM‐OFDM) for data transmission over mixed fiber‐FSO links to various end users at donut modes 0 and 1. This system enhances the fifth generation (5G)‐based networks reliability, survivability, and flexibility, especially in rural places where the core fiber link may be damaged/destroyed under diverse turbulent and weather conditions. The obtained results depict the faithful multimode fiber range of 100 km with fixed FSO range of 100 m at −17 dBm receiver sensitivity and low power penalty of 0.2 dB at 10−9 bit error rate. Maximum FSO range of 2800 m under weak‐to‐strong Gamma‐Gamma turbulence and the effect of fog, rain, snow, and snow with rain can be obtained successfully with fixed 50 km fiber length. Also, the proposed wheel architecture provides superior performance over hybrid ring‐mesh architecture with high split ratio of 1:64. Moreover, the system can sustain up to 70 remote nodes at symmetric 10 Gbps throughput providing high gain, high optical signal‐to‐noise ratio, and low noise figure. The comparative literature work also reveals that the proposed architecture offers high bandwidth, security, long‐reach, and cost‐effectiveness in 5G fronthaul/backhaul networks.

Integrated Sensor-Optics Communication System Using Bidirectional Fiber and FSO Channels and Hybrid Deep Learning Techniques.

This paper introduces a new bidirectional integration approach that combines fiber sensor/free space optics (FSO) communication using an intensity and wavelength division multiplexer (IWDM) techniques-based long-distance fiber Bragg grating (FBG) sensor strain-sensing system. By implementing coarse wavelength division multiplexing (CWDM), the system achieves the simultaneous transmission of optical communication and fiber optical sensor (FOS) sensing signals, resulting in a highly capable, flexible, and cost-effective solution. The proposed FSO transmission technique addresses complex fiber cable installation concerns with topographical limitations. This bidirectional structure ensures the reliability and stability of the long-distance FBG sensor system, supported by extensive research and experimentation. A hybrid stacked gated recurrent units and long short-term memory (SGRU-LSTM) model is proposed to enhance strain measurement accuracy by predicting and measuring the central wavelength of overlapped strain-sensing FBG sensor signals. The results demonstrate the superiority of the proposed model in peak wavelength detection accuracy. The primary benefit of integrating communication and sensing is the significant reduction in construction costs by eliminating the requirement for two individual fiber optic systems, as the integration allows for a single system to fulfill both functions, resulting in more efficient and cost-effective implementation. Overall, this paper contributes to advancing long-distance FBG sensor systems by integrating fiber sensor/FSO communication and deep learning techniques, improving transmission distance, multiplexing capacity, measurement accuracy, system survivability, and cost-effectiveness.

UAV-Aided Wireless Energy Transfer for Sustaining Internet of Everything in 6G

Unmanned aerial vehicles (UAVs) are a promising technology used to provide on-demand wireless energy transfer (WET) and sustain various low-power ground devices (GDs) for the Internet of Everything (IoE) in sixth generation (6G) wireless networks. However, an individual UAV has limited battery energy, which may confine the required wide-range mobility in a complex IoE scenario. Furthermore, the heterogeneous GDs in IoE applications have distinct non-linear energy harvesting (EH) properties and diversified energy and/or communication demands, which poses new requirements on the WET and trajectory design of UAVs. In this article, to reflect the non-linear EH properties of GDs, we propose the UAV’s effective-WET zone (E-zone) above each GD, where a GD is assured to harvest non-zero energy from the UAV only when the UAV transmits into the E-zone. We then introduce the free space optics (FSO) powered UAV with enhanced mobility, and propose its adaptive WET for the GDs with non-linear EH. Considering the time urgency of the different energy demands of the GDs, we propose a new metric called the energy latency time, which is the time duration that a GD can wait before becoming fully charged. By proposing the energy-demand aware UAV trajectory, we further present a novel hierarchical WET scheme to meet the GDs’ diversified energy latency time. Moreover, to efficiently sustain IoE communications, the multi-UAV enabled WET is employed by unleashing their cooperative diversity gain and the joint design with the wireless information transfer (WIT). The numerical results show that our proposed multi-UAV cooperative WET scheme under the energy-aware trajectory design achieves the shortest task completion time as compared to the state-of-the-art benchmarks. Finally, the new directions for future research are also provided.

Integrated photonic secured reliable DWDM for 5G Xhaul at Ka band frequency

This article investigates a secure reliable dense-wavelength-division-multiplexing (DWDM) with three different kinds of media for many geographic environments. A 80 Gb/s data transmission at Ka band (28 GHz) based three secure physical links using an optical chaotic signal, which applies a mask to hide the transmitted signal inside a generated chaos sketch. Based to the achieved results, the chaotic signal has a considerable effect on the free space optics than fiber optics. The simulation findings depict that the new model has an acceptance performance for all simulated links with 10-34 BER in the case of 4x4 FSO, but the ratio is degraded to 10-5 with increasing the distance of 3 Km. Similarly, the BERs are decreased from 10-32 to 10-8 when the coarse-DWM optical fiber is utilized; In the case of cascaded SMF-4x4 FSO, BER ratio is declined from 10-32 to 10-6. The proposed model has a best quality compared with the former chaotic studies and investigations.