Research Article |
Performance Analysis of RIS-Assisted Index Modulation for Terahertz Communications
Author(s): V. Shiva Bhasakar Rao*, and B. Suribabu Naick
Published In : International Journal of Electrical and Electronics Research (IJEER) Volume 12, Issue 4
Publisher : FOREX Publication
Published : 30 December 2024
e-ISSN : 2347-470X
Page(s) : 1474-1479
Abstract
The significance of Terahertz (THz) communication for the upcoming sixth generation (6G) communications, which offers abundant bandwidth for high-speed data transmission. However, THz frequencies face challenges such as propagation attenuation and molecular absorption that limit their coverage range. To address this issue, the use of reconfigurable intelligent surfaces (RIS) and index modulation (IM) has been proposed to extend coverage and reduce bit error rates (BER) at low transmitted power. This paper introduces a novel RIS-assisted IM system for THz communication, employing semi-definite relaxation (SDR) optimization techniques for passive beam forming at the detector. The proposed system, named PRIS-IM, demonstrates superior performance compared to conventional RIS-IM (CRIS-IM) and conventional IM (CIM) without RIS in THz frequencies. Simulation results illustrate a lower BER at a higher signal to-noise ratio (SNR) achieved by increasing the number of passive elements. Furthermore, the mutual information (MI) of the PRIS-IM system is derived and validated with simulation, and the achievable rate of the PRIS-IM system is improved by increasing the number of transmitting antennas and reflecting elements. Moreover, the PRIS-IM system is analyzed in different channel scenarios and distances. Overall, the proposed system exhibits the potential to significantly enhance the BER and MI performance of THz communication, indicating promising prospects for future wireless networks.
Keywords: Terahertz communication
, Reconfigurable intelligent surfaces Index modulation
, Bit error rate
, Semi-definite relaxation
, Mutual information
.
V. Shiva Bhasakar Rao*, Research Scholar, Department of EECE, GITAM (Deemed to be University), Rushikonda, Visakhapatnam, Andhra Pradesh, India; Email: sivabhaskarrao653@gmail.com
B. Suribabu Naick, Department of Electronics and Communication Engineering, GITAM (Deemed to be university), AP, 530045, India; Email: sbhukya@gitam.edu
-
[1] Akyildiz, I.F.; Han, C.; Nie, S., Combating the distance problem in the millimeter wave and terahertz frequency bands, IEEE Communications Magazine, 2018, 56, 102โ108.
-
[2] Basar, E., Reconfigurable intelligent surface-based in demodulation: A new beyond MIMO paradigm for6G, IEEE Transactions on Communications, 2020, 68, 3187โ3196.
-
[3] Basar, E.; Wen, M.; Mesleh, R.; DiRenzo, M.; Xiao, Y.; Haas, H., Index modulation techniques for next-generation wireless networks. IEEE access, 2017, 5, 16693โ16746.
-
[4] Canbilen, A.E.; Basar, E.; Ikki, S.S., Reconfigurable intelligent surface-assisted space shift keying, IEEE wireless communications letters, 2020, 9, 1495โ1499.
-
[5] Chapala, V.K.; Zafaruddin, S., Exact analysis of RIS-aided THz wireless systems over๐ผ-๐fading with pointing errors, IEEE Communications Letters, 2021, 25, 3508โ3512.
-
[6] Chen, Z.; Chen, W.; Ma, X.; Li, Z.; Chi, Y.; Han, C., Taylor expansion aided gradient descent schemes for IRS-enabled terahertz MIMO systems, in:2020 IEEE Wireless Communications and Networking Conference Workshops (WCNCW), IEEE, pp.1โ7.
-
[7] Do, H.; Cho, S.; Park, J.; Song, H. J.; Lee, N.; Lozano, A., Terahertz line-of-sight MIMO communication: Theory and practical challenges, IEEE Communications Magazine, 2021, 59, 104โ109.
-
[8] Dovelos, K.; Assimonis, S. D.; Ngo, H. Q.; Bellalta, B.; Matthaiou, M., Intelligent reflecting surfaces at tera hertz bands: Channel modeling and analysis, in:2021 IEEE International Conference on Communications Workshops (ICC Workshops), IEEE, pp.1โ6.
-
[9] Du, H.; Zhang, J.; Guan, K.; Ai, B.; Kรผrner, T.; Reconfigurable intelligent surface aided terahertz communications under misalignment and hardware impairments. arXivpreprintarXiv:2012.00267, 2020.
-
[10] Hao, W.; Sun, G.; Zeng, M.; Chu, Z.; Zhu, Z.; Dobre, O.A.; Xiao, P.; Robust Design for intelligent reflecting surface-assisted MIMO-OFDMA terahertz IoT networks, IEEE Internet of Things Journal, 2021, 8, 13052โ13064.
-
[11] Huang, C., Yang, Z.; Alexandropoulos, G.C.; Xiong, K.; Wei, L.; Yuen, C.; Zhang, Z, Hybrid Beamforming for RIS-Empowered Multi-hop Terahertz Communications: A DRL-based Method, in:2020 IEEE Globe com Workshops IEEE, pp.1โ6.
-
[12] Kumar, M. H.; Sharma, S.; Deka, K.; Bhatia, V., Intelligent reflecting surface assisted terahertz communications, in:2022 IEEE International Conference on Signal Processing and Communications(SPCOM), pp.1-5.
-
[13] Li, Q.; Wen, M.; Wang, S.; Alexandropoulos, G. C.; Wu, Y. C.; Space shift keying with reconfigurable intelligent surfaces: Phase Configuration designs and performance analysis, IEEE Open Journal of the Communications Society, 2021, 2, 322โ333.
-
[14] Melhem, S. B.; Tabassum, H., User pairing and outage analysis in multi-carrier NOMA-THz networks. IEEE Transactions on Vehicular Technology, 2022, 71,5546โ5551.
-
[15] Ning, B.; Wang, P.; Li, L.; Chen, Z.; Fang, J, Multi-IRS-Aided Multi-User MIMO in mm Wave/THz Communications: Apace-orthogonal scheme, IEEE Transactions on Communications, 2022, 70, 12, pp.8138-8152.
-
[16] Pan, Y.; Wang, K.; Pan, C; Zhu, H.; Wang, J, Sum-rate maximization for intelligent reflecting surface assisted terahertz communications, IEEE Transactions on Vehicular Technology, 2022, 71, 3, pp. 3320-3325.
-
[17] Polese, M.; Jornet, J.M.; Melodia, T.; Zorzi, M, Toward end-to-end, full-stack 6G terahertz networks, IEEE Communications Magazine, 2020, 58, 11, pp.48โ54.
-
[18] Sarieddeen, H.; Saeed, N.; Al-Naffouri, T.Y.; Alouini, M.S., Next Generation Terahertz Communications: A Rendezvous of sensing, imaging, and localization, IEEE Communications Magazine, 2020, 58, 69โ75.
-
[19] Wang, X.; Wang, J.; He, L.; Song, J.; Spectral efficiency analysis for downlink NOMA aided spatial modulation with finite alphabet inputs, IEEE Transactions on Vehicular Technology, 2017, 66, pp.10562โ10566.
-
[20] Yan, W.; Yuan, X.; He, Z.Q.; Kuai, X, Passive beam forming and information transfer design for reconfigurable intelligent surfaces aided multiuser MIMO systems, IEEE Journal on Selected Area sin Communications,2020, 38, pp.1793โ1808.