Performance Investigation of MIMO Based CO-OFDM FSO Communication Link for BPSK, QPSK and 16-QAM under the Influence of Reed Solomon Codes
DOI:
https://doi.org/10.5614/j.eng.technol.sci.2021.53.5.8Keywords:
BER, CO-OFDM, FSO, MIMO, Modified Gamma-Gamma, RS codes, SNRAbstract
The MIMO based CO-OFDM FSO communication system is emerging as a promising approach to meet the future bandwidth requirements for seamless communication. The atmosphere being the propagation medium is a major hindrance in wide-scale acceptability of FSO technology. For seamless and error-free transmission and reception of data, a novel concept of MIMO integrated with RS code is proposed in this paper. The system performance of an RS 64 (RS (255,127)) coded MIMO-based CO-OFDM FSO communication link was investigated using BPSK, QPSK and 16-QAM under the combined effects of geometric losses, path losses and atmospheric attenuations at a hitherto un-investigated data rate of 40 Gbps and a link distance of 5 km. The modified gamma-gamma distribution was used for modeling a moderately turbulent channel. With link length varying over a range of 1 to 5 km, error correction was maximum in 16-QAM as compared to BPSK and QPSK, with 150 to 167 corrected errors. In terms of PAPR, PSK was more apt than QAM, but with a compromise in BER. The geometric losses were reduced with link length due to an increase in error correction capability for all three modulation cases, with the least losses occurring in 16-QAM. At the target bit error rate (BER), the signal to noise ratio (SNR) required for BPSK and QPSK was higher by 3.98 dB and 6.14 dB compared to 16-QAM.
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Arnon, S., Barry, J.R., Karagiannidis, G.K., Schober, R. & Uysal, M. Advanced Optical Wireless Communication, Cambridge University Press, 2012. DOI: 10.1017/CBO9780511979187
Khalighi, M.A. & Uysal, M., Survey on Free Space Optical Communication: A Communication Theory Perspective, IEEE Communications Surveys and Tutorials, 16(4), pp. 2231-2258, 2014.
Kumar, S. & Payal, Enhancing Performance of FSO Communication Link Using Coherent Optical OFDM with Cascaded EDFA, 2020 5th International Conference on Communication and Electronics Systems (ICCES), COIMBATORE, India, pp. 349-355, 2020. DOI: 10.1109/ ICCES48766.2020.9138043.
Miglani, R. & Malhotra, J., Statistical Analysis of FSO Links Employing Multiple Transmitter/ Receiver Strategy over Double-Generalized and Gamma?Gamma Fading Channel Using Different Modulation Techniques, Journal of Optical Communications, 40(3), pp. 295-305, 2018. DOI: 10.1515/joc-2017-0066.
Kaushal, H., Jain, V.K. & Kar, S., Free Space Optical Communication, Optical Networks, 1st edn., Springer, 2017. DOI: 10.1007/978-81-322-3691-7.
Bhatnagar, M.R. & Ghassemlooy, Z., Performance Analysis of Gamma-Gamma Fading FSO MIMO Links with Pointing Errors, Journal of Lightwave Technology, 34, pp. 2158-2169, 2016.
Yang, L., Gao, X. & Alouini, M.S., Performance Analysis of Free-Space Optical Communication Systems with Multiuser Diversity Over Atmospheric Turbulence Channels, IEEE Photonics Journal, 6, pp. 1-17, 2014.
Nistazakis, H.E. & Tombras, G.S., On the Use of Wavelength and Time Diversity in Optical Wireless Communication Systems over Gamma-Gamma Turbulence Channels, Journal of Optics and Laser Technology, 44, pp. 2088-2094, 2012.
Sharma, M., Chadha, D. & Chandra, V., Performance Analysis of MIMO-OFDM Free Space Optical Communication System with Low-Density Parity-Check Code, Photonic Network Communications, 32(1), pp. 104-114, 2016.
Sharma, M., Chadha, D. & Chandra, V., Capacity Evaluation of MIMO-OFDM Free Space Optical Communication System, 2013 Annual IEEE India Conference (INDICON), Mumbai, pp. 1-4, 2013. DOI: 10.1109/INDCON.2013.6726078.
Prabu, K., Sriram Kumar, D. & Malekian, R., BER Analysis of BPSK-SIM-Based SISO and MIMO FSO Systems in Strong Turbulence with Pointing Errors, Optik-International Journal for Light and Electron Optics, 125(21), pp. 6413-6417, 2014.
Sonar, N.S. & Mudholkar, R.R., Analytical Study of Reed-Solomon Error Probability, International Journal of Engineering Studies, 8(2), pp. 297-304, 2016.
Chronopoulos, S.K., Christofilakis, V., Tatsis, G. & Kostarakis, P., Performance of Turbo Coded OFDM under the Presence of Various Noise Types, Wireless Personal Communications, 87(4), pp. 1319-1336, 2016.
Djordjevic, I.B., Vasic, B. & Neifeld, M.A., LDPC Coded OFDM over the Atmospheric Turbulence Channel, Optics Express, 15, pp. 6336-6350, 2007.
Chaudhary, S., Amphawan, A. & Nisar, K., Realization of Free Space Optics with OFDM under Atmospheric Turbulence, Optik, 125, pp. 5196-5198, 2014.
Sharma, V. & Kaur, G., High Speed, Long Reach OFDM-FSO Transmission Link Incorporating OSSB and OTSB Schemes, Optik, 124, pp. 6111-6114, 2013.
Sushank, V.S., High Speed CO-OFDM-FSO Transmission System, Optik, 125, pp. 1761-1763, 2014.
Kakati, D. & Arya, S.C., A Full-Duplex Optical Fiber/Wireless Coherent Communication System with Digital Signal Processing at the Receiver, Optik, 171, pp. 190-199, 2018.
Mane, P.B. & Belsare, M.H., Evaluation of the Performance of a Reed Solomon Coded STBC MIMO System Concatenated with MPSK and MQAM in Different Channels, International Journal of Sensors, Wireless Communications and Control, 10(2), pp. 153-163, 2020. DOI: 10.2174/2213275912666190410151455
Sanghvi, A.S., Mishra, N.B., Waghmode, R. & Talele, K.T., Performance of Reed-Solomon Codes in AWGN Channel, International Journal of Electronics and Communication Engineering, 4(3), pp. 259-266, 2011.
Kaur, S., Singh, N., Kaur, G. & Singh, J., Performance Comparison of BPSK, QPSK and 16-QAM Modulation Schemes in OFDM System using Reed Solomon Codes, 2018 International Conference on Recent Innovations in Electrical, Electronics & Communication Engineering (ICRIEECE), Bhubaneswar, India, 2018, pp. 530-533, DOI: 10.1109/ICRIEECE44171.2018.9008983.
Kapoor, M. & Khare, A., Performance Analysis of Reed Solomon Code for Various Modulation Schemes over AWGN Channel, International Journal of Applied Engineering Research, 12 (17), pp. 6391-6398, 2017.
Miglani, R. & Malhotra, J.S., Investigation on R-S Coded Coherent OFDM Free Space Optical (CO-OFDM-FSO) Communication Link over Gamma-Gamma Channel, Wireless Personal Communications, 109, pp. 415-435, 2019. DOI: 10.1007/s11277-019-06571-z.
Kumar, S. & Arora, P., Impact of Reed Solomon Forward Error Correction Code in Enhancing Performance of Free Space Optical Communication Link, Proc. SPIE 11506, Laser Communication and Propagation through the Atmosphere and Oceans IX, 1150605, 2020. DOI: 10.1117/12.2567835
Sandoval, F., Poitau, G., & Gagnon, F., On Optimizing the PAPR of OFDM Signals with Coding, Companding, and MIMO. IEEE Access, 7, pp. 24132-24139, 2019. DOI: 10.1109/ACCESS.2019.2899965.
Kumar, S. & Arora, P., Modeling C2n by Inclusion of Rainfall Parameter and Validate Modified Log Normal and Gamma-Gamma Model on FSO Communication Link, Journal of Optical Communications, AOP, 2019. DOI: 10.1515/joc-2019-0247.