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Optical Wireless Communication - Literature review Example

Summary
This work "Optical Wireless Communication" describes a complementary technology to the convectional RF wireless communications systems. The author outlines the benefits of the technology that OWC remains as the most attractive solution, especially when it comes to environment settings where radio communications are likely to encounter difficulties…
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Extract of sample "Optical Wireless Communication"

Optical Wireless Communication Name: Institution: Date: Table of Contents 1.0.Literature Review---Optical Wireless Communication 3 2.0.Radio Frequency Communication and Optical Communications 5 3.0.Benefits of Optical Wireless Communication 6 4.0.Optical Wireless Communication Modulation 6 5.0.Application of MATLAB in Optical Wireless Communication 6 6.0.On-off keying- Non Return to Zero Modulation Scheme 7 7.0.The Difference between OOK-NRZ modulation and QAM Modulation Schemes 7 8.0.Optical Wireless Communication System Components 7 9.0.Photo-detector types and its characterisation (PIN and APD)  9 Optical Wireless Communication 1.0. Literature Review---Optical Wireless Communication Studies on optical wireless communication (OWC) remain multifaceted. Contemporary studies from scholars such as Li et al. (2013) have indicated that OWC is drawing significant attention since it is viewed as a complementary technology to the convectional RF wireless communications systems. According to Malekiha et al. (2013) the technology, (OWC) is having higher data rate when compared with RF wireless communication systems. This view has been supported by Mesleh et al. (2011) who see the technology as cost-effective and enhanced security and avoidance of interference, freedom from spectrum licensing regulation and protocol transparency. Studies that have been concerned with the benefits of the technology agree that OWC remains as the most attractive solution, especially when it comes to environment settings where radio communications are likely to encounter difficulties. To conceptualise this point, Li et al. (2013) introduce its applicability as used by the Fraunhofer Heinrich Hertz Institute (HHI) which applied modern transmission techniques that necessitated data-rates which went up to 1,25 Gbit/s. Hwang et al. (2012) did propose a complex system in which there is a link between WLANs and fiber optic network for expansion of DAS along the channels of distribution in an economical way. In their paper, they show a DAS wireless bridge design applicable in network communication using IEEE 802.11 and an available experimental check on the effectiveness and sensitivity of the transmission signal. Malekiah et al. (2013) have examined Optical back propagation techniques which make use of two highly nonlinear fibers to compensate for transmission fiber nonlinear effects. Amiri et al. (2014) conclude that there are numerous advantages that the wireless networks have over the wire systems such as mobility services and non-requirement of the cabling. The research shows the broad application of OFDM modulation and multiplexing technology which forms the foundation wireless and wired communication channels. The handling of simulation of the result of the mathematical equations of the ring systems solved by the Z-transform method is achievable by coding from MATLAB software. Mesleh et al. (2011) did the analysis of the performance of indoor orthogonal frequency division multiplexing (OFDM) optical wireless communication systems in light emitting diode (LED) nonlinear distortions. They found out that LED clipping has a significant effect on the functionality of the two arrangements and further suggests that an original arrangement scheme ought to apply LED dynamic range, DC-bias point, and OFDM signal power. Shahidinejad et al. (2014) describe the current state of Wavelength Division Multiplexing based Optical Wireless Communication system. The paper gives a vivid investigation of the problems that the system faces and concludes with the proposition of the Solitonic pulse shape when it comes to indoor WDM-based OWC by adopting Micro-Ring Resonators (MRR) to overcome the challenges. The finding of the research indicates that the generation of ultra-short 23 picosecond solitonic pulses could be applicable in the improvement of Wavelength Division Multiplexing based Optical Wireless Communication Systems. Zhou et al. (2010) did a systematic analysis of the security factors of Optic based Information Communication Infrastructure‘s (OICl) physical layer. Fidler et al. (2010) review high-altitude platforms (HAPs) and experimental field trials for optical communications and. They also discuss tracking and acquisition of laser terminals and a description of how laser beams with small divergence to transmit data at multi-Gigabits per second. Wu et al. (2013) examine a novel fiber-optic chaos synchronization system allowing bi-directional long-distance chaos communication. Xu et al.(2013) introduced the use of a single fiber optical sensor system used to measure the refractive index (RI). Li et al. (2013) propose and experimentally demonstrate millimeter wave (mm-wave) generation in the S-band (71-76 GHz and 81-86 GHz) based on photonics production technique. Wu et al. (2013) propose a novel method for modulation format-transparent polarization tracking and DE multiplexing in a coherent; polarization multiplexed fiber-optic communication system. Bhosale and Deosarkar (2013) analyzed the technology for encoding and decoding of coherent ultrashort light pulses based on random phase codes and wavelength/time (W/T) codes. 2.0. Radio Frequency Communication and Optical Communications To begin with, Radio Frequency and Optical Wireless Communications are used in the practical fields. The usage of each of the technologies is dependent on its ability and requirements in the particular area of application. Optical wireless communications is the form of optical communication where unguided visible, infrared (IR), or ultraviolet (UV) light is used to carry signals (Li et al. 2013). When operating in the visible band (390-750nm), the OWC systems are commonly referred to as visible light communication (VLC). RF is limited to the constraint of the bandwidth yet is the most suitable for communication over long distance. In optical communications, the data rate changes and is usable where the line of sight is not problematic for the communication links. RF communication can also be used together with other technologies to improve the data rate (Zhao et al. 2015). 3.0. Benefits of Optical Wireless Communication Optical wireless communication offers various benefits owing to its feature: does not have electromagnetic interference (EMI) with radio systems, has unregulated spectrum (optical frequencies) with worldwide availability and simple shielding by opaque surfaces (improved privacy). Studies that have compared benefits of OWC have noted that the technology is built to penetrate the wireless networks, walls and are easy to install at any point one chooses. This view has been supported by Moore (2011) who argued about its flexibility as one of its flexibility especially where wired cable cannot be established or installed. 4.0. Optical Wireless Communication Modulation Modulation is the provision of additional information to an optical or electronic carrier signal (Wu et al. 2013). However, the addition of information for optical signals is possible by changing polarization, phase, frequency, amplitude, and even quantum-level phenomena such as spin. There are various types of modulation application in optical wireless communication including improved differential pulse position modulation, pulse position modulation, binary pulse interval modulation, digital pulse interval modulation, differential pulse position modulation, and on-off keying modulation (Zhao et al. 2015). 5.0. Application of MATLAB in Optical Wireless Communication MATLAB software can be used in optical wireless communication to build codes for measuring spectral efficiency, the data rate and bit error rate which have a direct relation to the performance of optical wireless communication (Wang et al. 2014). 6.0. On-off keying- Non Return to Zero Modulation Scheme On-off keying modulation has a basis on the ability modulation with detection that are direct as the simplest way in the digital wireless optical systems. The production of the optical pulse is achievable via opening and breaking of lasers during information “I” sending process while the light pulse is forwarded when information “0” sending process, the laser is shut down completely. 7.0. The Difference between OOK-NRZ modulation and QAM Modulation Schemes No return to zero (OOK-NRZ) modulation differs from quadrature amplitude modulation (QAM) modulation scheme in that OOK-NRZ forms an easier way without synchronizing symbols (Zhao et al. 2015). On the other hand, OOK-NRZ has a smaller bandwidth demand and larger transmission capacity with the lowest power usage compared to QAM modulation scheme. In comparison to non-return to zero systems, the quadrature amplitude modulation has higher energy efficiency. The two modulation methods present different cons and pros, but quadrature amplitude modulation is more suitable for the future of wireless optical communication systems. 8.0. Optical Wireless Communication System Components Transmitter The antenna forms the commencing point optical communication where modulation of the optical source converts electrical signal to optical signal. The laser diode (LD) and Light-emitting diode (LED) are the most common machines utilized as the light source in the optical transmitters. The light emitters are the costly element in the system fitted with semiconductors that convert the electrical signals into corresponding light signals able of ejection into the fiber (Takai et al. 2013). LED and LASER differ r in their functionality and design. LED is a property adopted as optical fiber transmitters to emit infrared radiation. The wavelength approximated for this case is about (0.85 µm). On the other hand, LASER produces infrared radiation or intense beam of light with the following properties: Collimated Monochromatic and Coherent Connecting these points to the differences between edge emitting and surface emitting LEDs is that the two can be compared in terms of use in high-data-rate fiber-optimal systems of communication. As compared to edge emitting LEDs, surface emitting LEDs have thick window type of diode (about 20-25-µm) within the context of output power and rates of data. On the other hand, LED modulation bandwidth is expressed as the modulation frequency found at the LED power transfer function. 9.0. Photo-detector types and its characterisation (PIN and APD)  Beginning with channel, it is composed of optical fiber either single mode or multimode connecting the transmitter and the receiver. A plastic buffer of a coating is used to provide strength and protection to the fiber. The receiver either an APD or a PIN photodiode to receive the optical signal and convert it back to electrical signal. The conversation of the data back to its original form is accomplishable by a data demodulator. Photo-detection Noises entails shot noise, dark noise and thermal noise. Beginning with thermal noise (also known as Johnson noise), Zhao et al. (2015) argue that the noise is generated as a result of random carriers functions that are brought about by the photodiode resistance that provide a thermal agitation since the Brownien motion often produce a random voltage at the extremities of resistance. In most case, this noise can be referred to as dark noise. Differently, shot noise, sometime referred as quantum noise depends on the corpuscular position of electron as well as their random emission or collection with regard to time. Just like Zhao et al. (2015) noted, performance of noise and hence the signal to noise ratio is critical for any radio receiver. Therefore, SNR is the measure of the sensitivity performance concerning a receiver. Conversely, Q-factor is considered as dimensionless measure that explains the extent to which under-damped resonator or oscillator is and this is where eye diagram is essential as it provides some indication (visual one) on the extent noise can affect system performance. Optic fibers find broad application in the transmission of information as a versatile medium. LASER is preferred to LED since it uses both MMF and SMF. Optical fiber has a significant use for DAS for satellite, communication, and electricity distribution. However, fog, rain and other factors can affect the signal because they can either disrupt broadband services or misalign dish resulting in interruptions. Optical wireless communication offers various benefits owing to its feature: does not have electromagnetic interference (EMI) with radio systems, has unregulated spectrum (optical frequencies) with worldwide availability and simple shielding by opaque surfaces. The link between OWC and Li-Fi is based on data transfer. Unlike Wi-Fi, Li-Fi is the best product for extending wireless networks to different places including homes especially where there is need for data transfer that extends beyond 10 Gbps. References Amiri, I. S., Nikoukar, A., Shahidinejad, A., & Anwar, T. (2014). The Proposal of High Capacity GHz Soliton Carrier Signals Applied for Wireless Communication. Reviews in Theoretical Science, 2(4), 320-333. Bhosale, S. R., & Deosarkar, S. B. (2013, January). Design and performance analysis of a newly designed 32-user Spectral Phase Encoding system operating at 2.5 Gb/s for fiber-optic CDMA networks. In Advanced Communication Technology (ICACT), 2013 15th International Conference on (pp. 33-40). IEEE. Fidler, F., Knapek, M., Horwath, J., & Leeb, W. R. (2010). Optical communications for high-altitude platforms. IEEE Journal of Selected Topics in Quantum Electronics, 16(5), 1058-1070. Li, X., Yu, J., Dong, Z., & Chi, N. (2013). Photonics millimeter-wave generation in the E-band and bidirectional transmission. IEEE Photonics Journal, 5(1), 7900107-7900107. Malekiha, M., Yang, D., & Kumar, S. (2013). Comparison of optical back propagation schemes for fiber-optic communications. Optical Fiber Technology, 19(1), 4-9. Mesleh, R., Elgala, H., & Haas, H. (2011). On the performance of different OFDM based optical wireless communication systems. Journal of Optical Communications and Networking, 3(8), 620-628. Moore III, R. M. (2011). U.S. Patent No. 7,991,353. Washington, DC: U.S. Patent and Trademark Office. Shahidinejad, A., Amiri, I. S., & Anwar, T. (2014). Enhancement of indoor wavelength division multiplexing-based optical wireless communication using microring resonator. Reviews in Theoretical Science, 2(3), 201-210. Takai, I., Ito, S., Yasutomi, K., Kagawa, K., Andoh, M., & Kawahito, S. (2013). LED and CMOS image sensor based optical wireless communication system for automotive applications. IEEE Photonics Journal, 5(5), 6801418-6801418 Wang, C. X., Haider, F., Gao, X., You, X. H., Yang, Y., Yuan, D., ... & Hepsaydir, E. (2014). Cellular architecture and key technologies for 5G wireless communication networks. IEEE Communications Magazine, 52(2), 122-130. Wu, J. G., Wu, Z. M., Liu, Y. R., Fan, L., Tang, X., & Xia, G. Q. (2013). Simulation of bidirectional long-distance chaos communication performance in a novel fiber-optic chaos synchronization system. Journal of Lightwave Technology, 31(3), 461-467. Wu, Z., Schmidt, D., & Lankl, B. (2013). Modulation-format-transparent polarization tracking using a neural network. IEEE Photonics Technology Letters, 25(7), 671-674. Xu, W., Huang, X. G., & Pan, J. S. (2013). Simple fiber-optic refractive index sensor based on fresnel reflection and optical switch. IEEE Sensors Journal, 13(5), 1571-1574. Zhao, N., Li, X., Li, G., & Kahn, J. M. (2015). Capacity limits of spatially multiplexed free-space communication. Nature Photonics, 9(12), 822-826.. Zhou, J., Chen, X., Zhao, Z., & Li, J. (2010, October). Research in security of optic-based information communication architecture for next generation power system applications. In Power System Technology (POWERCON), 2010 International Conference on (pp. 1-5). IEEE. Read More
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