Research on the Application of Terahertz Communication Technology in 5G and Future Networks

Lu Bai

doi:10.54254/2755-2721/99/20251750

1. Introduction

In the era of rapid development of mobile communication technology, the demand for wireless communication services continues to grow, and the expectations for data transmission rates, network capacity, and service quality are also increasing. Although the fifth generation of mobile communication technology (5G) has achieved significant improvements in aspects such as speed, latency, and connection density, it still faces challenges in the limited availability of spectrum resources and the capability for large-scale data transmission in the face of future networks development trends and user demands[1].

In this context, the concept of the sixth generation of mobile communication technology (6G) has emerged, and its commercialization is expected around 2030. The vision of 6G is to build a more extensive and in-depth world of wireless connections, serving not only human society but also expanding to intelligent agents, machines, and objects, achieving “intelligent connection of all things”. 6G aims to achieve global seamless coverage, provide virtually unlimited spectrum resources, support ultra-high-speed data transmission, extremely low latency, and high reliability[2]. In order to achieve these ambitious goals, 6G needs to explore and utilize new spectrum resources, among which the terahertz (THz) band, due to its abundant spectrum resources, has become one of the key technologies. This study aims to discuss how terahertz communication technology, as a key component of 6G technology, can overcome the limitations of 5G and achieve the ambitious goals of 6G. This paper will conduct an in-depth analysis from the basic theories, key technologies, channel characteristics, and modeling of terahertz communication technology, and discuss its application prospects in 6G and future networks, as well as the challenges it faces.

2. Overview of Terahertz communication technology

Terahertz (THz) lies between microwaves and infrared light, and it has a bandwidth wider than that of the existing 5G. Theoretically, it is capable of achieving data transmission rates up to the Tbps level[3]. Additionally, the short-wavelength characteristics of THz waves contribute to higher spectral efficiency and system capacity, enabling smaller antenna sizes and denser antenna array layouts[4]. Furthermore, the advantages of THz waves, such as strong penetration and good physical properties for anti-interference, provide potential for widespread application in the field of wireless communication. Figure 1 illustrates the frequency and wavelength spectrum of the electromagnetic spectrum.

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Figure 1: The Position of Terahertz Waves in the Wireless Spectrum[5].

Terahertz communication technology is an emerging wireless communication method that utilizes terahertz waves (typically referring to the frequency range from 0.1 THz to 10 THz) between microwaves and infrared light for information transmission. This technology leverages the electromagnetic properties of terahertz waves, which have shorter wavelengths and higher frequencies, allowing them to carry more information within a limited space, thus offering a clear advantage over traditional 5G technology in terms of spectrum resources[6]. Moreover, in various fields such as broadband wireless access[7], security surveillance[8], global environmental monitoring[9], industrial automation[10], and medical imaging[11], terahertz communication technology has shown significant potential for application. However, its wide application in 6G and future networks will require overcoming challenges in multiple aspects, including technology, cost, and standardization. Future research needs to address device performance and system design challenges while achieving breakthroughs in the fields of electronic, photonic, and plasmonic wave devices to realize its broad application in high-speed wireless communication.

3. Terahertz communication-related technologies

3.1. Electronics, optics, and plasmonics in Terahertz

Terahertz electronics, as the core of the development of terahertz communication technology, involves two major technological directions: vacuum electronic devices and solid-state electronic devices[12]. Vacuum electronic devices, such as cyclotrons and magnetrons, have garnered significant attention due to their potential in high-frequency applications. Innovations in these devices primarily focus on enhancing operating frequencies, efficiency, and reducing size and cost. For instance, by improving the design of electron guns and optimizing cavity structures, the performance of these devices can be significantly improved[13]; solid-state electronic devices, including high-electron-mobility transistors (HEMTs)[14] and THz CMOS, play a pivotal role in signal amplification, oscillation, and mixing at terahertz frequencies[15]. With the advancement of integration technology, it has become possible to miniaturize and produce these devices at low cost while improving performance and reliability.

Two other key areas of terahertz communication devices are terahertz photonics and plasmonic wave devices. Terahertz photonics is becoming a key force in driving the development of 6G communication technology. This technology combined the unique characteristics of photonics and terahertz waves to achieve high-speed data transmission at high frequencies, e.g., 103.125 Gbps at the 370 GHz frequency band[16]. Advances in fiber-terahertz-fiber seamless communication technology have not only improved the efficiency and reliability of data transmission but also provided support for system flexibility and scalability. Furthermore, the overall performance and spectral efficiency of communication systems have been further improved by optimizing algorithms to enhance the performance of fiber amplifiers and utilizing neural network technology to optimize modulation and demodulation processes[17]. The integration of these technologies heralds the realization of unprecedented high-speed, high-capacity, and low-latency communication capabilities in 6G communication. Terahertz plasmonic wave devices, such as graphene-based metasurfaces and MIMO antennas[18], are propelling the development of 6G communication technology, offering high-speed data transmission and intelligent beam control, and providing innovative solutions for the high-frequency, low-power, and wide-bandwidth requirements of 6G communication.

The development of terahertz (THz) devices plays a crucial role in advancing 6G wireless communication technology. however, the field still faces a series of innovations and challenges. Currently, innovations in THz devices are primarily focused on enhancing the frequency, output power, and efficiency of the devices, as well as achieving wider operating bandwidths and higher levels of integration[19]. Additionally, issues such as propagation loss, atmospheric attenuation, and diffraction limitations in the terahertz band urgently need to be addressed[20]. To overcome these challenges, researchers are exploring advanced technologies such as intelligent reconfigurable reflective arrays and multiple-input multiple-output (MIMO) antenna arrays, as well as developing new channel measurement and modeling methods, with the aim of achieving more efficient and reliable terahertz communication systems.

3.2. System design and implementation

3.2.1. MIMO technology

In the field of terahertz communication, multiple-input multiple-output (MIMO) technology is one of the key technologies for enhancing spectral efficiency and signal transmission reliability. According to research, a large-scale antenna array can be deployed in a compact device by utilizing the extremely short wavelength of the terahertz band[20]. This compact antenna array layout not only helps to improve the system's spectral efficiency but also significantly increases system capacity through spatial multiplexing techniques. In addition, it was pointed out that MIMO systems in the terahertz band can achieve precise control over signal propagation paths by adjusting the configuration of the antenna arrays to optimize communication quality[21].

In system design, researchers have explored MIMO technology based on the terahertz band to achieve efficient spatial multiplexing and beamforming[22]. It was mentioned that the combination of intelligent reconfigurable intelligent surface (RIS) technology with MIMO technology can further enhance signal transmission effects. RIS technology can dynamically adjust the reflection and refraction of signals, thereby achieving precise control over signal beams without incurring additional hardware costs.

3.2.2. RIS technology

Intelligent Reconfigurable Intelligent Surface (RIS) technology is another key technology in terahertz communication systems. RIS can dynamically adjust the propagation path of wireless signals by altering the reflection phase of its elements to optimize the signal coverage and enhance the signal strength[12]. The application of this technology enables high-quality terahertz communication even in complex indoor environments.

In terms of system implementation, a terahertz communication system design based on RIS was proposed, which achieves dynamic adjustment of signal beams by precisely controlling the phase response of RIS elements[23]. This design not only improves signal transmission efficiency but also enhances the system’s anti-interference capabilities. Furthermore, research explores the application prospects of RIS technology in terahertz communication, noting that RIS technology is expected to play a significant role in future 6G communication networks[24].

MIMO technology and RIS technology play a crucial role in the design of terahertz communication systems. By combining these two technologies, researchers can design more efficient and reliable terahertz communication systems to meet the future wireless communication demands for high data rates and high connectivity density. Implementing these technologies requires not only innovation in existing hardware devices but also the development of new channel measurement and modeling methods to accommodate the unique propagation characteristics of the terahertz band.

3.3. Channel characteristics and modeling

Channel characterization and modeling for terahertz communication is fundamental to achieving efficient and reliable communication systems. Atmospheric conditions, including temperature, humidity, and air pressure, as well as environmental factors such as rain, snow, fog, and sand, can all affect the propagation of terahertz signals. For instance, additional attenuation introduced by rain and signal scintillation caused by atmospheric turbulence can affect the phase and amplitude stability of signals[25]. Therefore, in-depth study of channel models is crucial for predicting and adapting to these effects.

Terahertz communication channel modeling typically employs deterministic and statistical modeling methods. Deterministic modeling is based on the physical principles of electromagnetic wave propagation, aims to describe the physical processes and parameters of the channel in detail, and seeks to accurately predict channel characteristics. However, it is not suitable for real-time systems due to high computational complexity[26]. In contrast, statistical modeling focuses on the statistical distribution of channel characteristics, describes the channel's stochastic properties with simplified mathematical models, and is widely applied in system performance analysis and design. However, it may not be able to capture all details of the channel and thus has certain limitations[27]. In conclusion, different channel modeling approaches can be selected for different application scenarios.

Hybrid modeling techniques combine the advantages of both deterministic and statistical modeling and can achieve a balance between accuracy and computational efficiency[28]. Specifically, deterministic modeling can be used to describe the main propagation paths, while statistical modeling can describe the randomness of multi-path effects and environmental factors. Additionally, hybrid modeling techniques can be integrated with machine learning and artificial intelligence technologies to optimize parameters based on existing training data, thus enhancing the model's adaptability and predictive accuracy, which is especially suitable for applications with higher accuracy requirements and higher implementation efficiency[29]. Based on the above analysis, the channel modeling for satellite-terrestrial terahertz communication needs to consider many factors.

In summary, an in-depth analysis of the characteristics of terahertz communication channels and the application of appropriate modeling methods are indispensable. This plays a key role in understanding and predicting the performance of communication systems in complex atmospheric environments, and also provides a solid theoretical basis and technical support for the development and application of terahertz communication technology.

4. Future research directions of Terahertz communication technology

As a new generation of intelligent comprehensive digital information infrastructure, 6G technology has become a focal point of competition among major countries around the world. Nations are actively advancing the research of 6G key technologies through the release of national strategies, deployment of significant projects, and international cooperation[30]. Although a consensus has basically been reached on the vision and typical application scenarios of 6G, the specific directions of key technologies have not yet been defined. Currently, 6G research is at an important stage of concept formation and key technology reservation.

As a primary frequency band for future communications, there are numerous future research directions and technologies worth exploring beyond existing methods to better harness the terahertz band for communications. Terahertz communication forms specific transmission windows due to its transmission losses at different distances and frequency bands, which possess varying bandwidth characteristics[31]. Given the richness of terahertz frequency resources, optimizing the selection and full utilization of different frequency bands, transmission distances, and transmission windows to meet diverse communication demands becomes a key issue for future research in the field of terahertz communication.

Furthermore, with the rapid development of artificial intelligence technologies, especially machine learning and neural networks, their application in wireless communication has become an area of great interest. Machine learning methods have proven to be very effective in solving high-dimensional and non-convex problems in hybrid precoding algorithms, offering solutions with lower complexity[32]. By incorporating machine learning, future communication systems will become more intelligent, being capable of adaptively managing and optimizing resources to meet the growing communication demands and providing more personalized services.

5. Conclusion

This paper has delved into the potential applications and challenges of terahertz communication technology in 5G and future 6G networks. The abundant spectral resources of the terahertz band offer the possibility of achieving ultra-high-speed data transmission, extremely low latency, and high reliability, making terahertz communication technology a strong candidate for key technologies in 6G networks. However, challenges in technology, cost, and standardization still need to be overcome. This paper has reviewed the fundamental theories, key technologies, channel characteristics, and modeling of terahertz communication technology and discussed its application prospects in 6G and future networks. Although this paper provides a comprehensive analysis, the lack of experimental validation limits the testing of theoretical models and assumptions. Furthermore, there is insufficient discussion on the specific implementation details and cost-benefit analysis of terahertz communication technology. Future research should incorporate experimental validation to test and optimize theoretical models, in-depth studies on device design and system integration, and cost-benefit analysis to explore the commercial potential and market applications of terahertz communication technology.

In summary, terahertz communication technology demonstrates significant potential for application in 6G networks but also confronts dual challenges in technological implementation and cost-effectiveness. The analysis in this paper provides a solid theoretical foundation for understanding terahertz communication technology, but future work requires more in-depth exploration in experimental validation, research on technical details, and cost-benefit analysis. The supplementary studies facilitate a more comprehensive understanding of terahertz communication technology, thereby establishing a robust foundation for its deployment in 6G and future networks.

References

[1]. Campos, R., Ricardo, M., Pouttu, A., & Correia, L. M. (2023). Wireless technologies towards 6G. EURASIP Journal on Wireless Communications and Networking, 2023(1). doi.org/10.1186/s13638-023-02250-7

[2]. Ahmad, I., Rodriguez, F., Huusko, J., & Seppänen, K. (2023). On the Dependability of 6G Networks. Electronics, 12(6), 1472. https://doi.org/10.3390/electronics12061472

[3]. Akyildiz, I., Jornet, J., & Han, C. (2014). TeraNets: ultra-broadband communication networks in the terahertz band. IEEE Wireless Communications, 21(4), 130–135. https://doi.org/10.1109/mwc.2014.6882305

[4]. Gallerano, G.P., & Biedron, S.G. (2004). OVERVIEW OF TERAHERTZ RADIATION SOURCES.In: Proceedings of the 2004 FEL Conference. Trieste. pp. 216-221.

[5]. Shi, L., Zahid, A., Ren, A., Ali, M. Z., Yue, H., Imran, M. A., Shi, Y., & Abbasi, Q. H. (2023c). The perspectives and trends of THz technology in material research for future communication - a comprehensive review. Physica Scripta, 98(6), 065006. https://doi.org/10.1088/1402-4896/accd9d

[6]. Elayan, H., Amin, O., Shihada, B., Shubair, R. M., & Alouini, M. (2019). Terahertz Band: the last piece of RF spectrum puzzle for communication systems. IEEE Open Journal of the Communications Society, 1, 1–32. https://doi.org/10.1109/ojcoms.2019.2953633

[7]. Liu, C., Wang, C., & Cao, J. C. (2017). Multipath propagation channel modeling and capacity analysis for terahertz indoor communications. Journal of Optical Technology, 84(1), 53. https://doi.org/10.1364/jot.84.000053

[8]. Hejase, J. A., Paladhi, P. R., & Chahal, P. P. (2011). Terahertz characterization of dielectric substrates for component design and nondestructive evaluation of packages. IEEE Transactions on Components Packaging and Manufacturing Technology, 1(11), 1685–1694. https://doi.org/10.1109/tcpmt.2011.2163632

[9]. Klug, M. T., Milot, R. L., Patel, J. B., Green, T., Sansom, H. C., Farrar, M. D., Ramadan, A. J., Martani, S., Wang, Z., Wenger, B., Ball, J. M., Langshaw, L., Petrozza, A., Johnston, M. B., Herz, L. M., & Snaith, H. J. (2020). Metal composition influences optoelectronic quality in mixed-metal lead–tin triiodide perovskite solar absorbers. Energy & Environmental Science, 13(6), 1776–1787. https://doi.org/10.1039/d0ee00132e

[10]. Naftaly, N., Vieweg, N., & Deninger, N. (2019). Industrial Applications of Terahertz Sensing: State of play. Sensors, 19(19), 4203. https://doi.org/10.3390/s19194203

[11]. Vaks, V. L., Anfertev, V. A., Balakirev, V. Y., Basov, S. A., Domracheva, E. G., Illyuk, A. V., Kupriyanov, P. V., Pripolzin, S. I., & Chernyaeva, M. B. (2019). High resolution terahertz spectroscopy for analytical applications. Physics-Uspekhi, 63(7), 708–720. https://doi.org/10.3367/ufne.2019.07.038613

[12]. Zhao Z. (2024) .New progress in THz electronics, photonics, plasma wave devices and applications for 6G wireless communication.Micronanoelectronic Technology(06), 7-27.doi:10.13250/j.cnki.wndz.24060101.

[13]. Hu, P., Lei, W., Jiang, Y., Huang, Y., Song, R., Chen, H., & Dong, Y. (2019). Demonstration of a Watt-Level traveling wave tube amplifier operating above 0.3 THz. IEEE Electron Device Letters, 40(6), 973–976. https://doi.org/10.1109/led.2019.2912579

[14]. Crabb, J., Cantos-Roman, X., Aizin, G. R., & Jornet, J. M. (2022). Amplitude and frequency modulation with an On-Chip Graphene-Based plasmonic terahertz nanogenerator. IEEE Transactions on Nanotechnology, 21, 539–546. https://doi.org/10.1109/tnano.2022.3208084

[15]. Spasaro, M., & Zito, D. (2022). Sub-MW 30GHz Variable-Gain LNA in 22Nm FDSOI CMOS for Low-Power tapered MM-Wave 5G/6G Phased-Array receivers. 2022 IEEE/MTT-S International Microwave Symposium - IMS 2022. https://doi.org/10.1109/ims37962.2022.9865340

[16]. Zhang, J., Zhu, M., Hua, B., Lei, M., Cai, Y., Zou, Y., Tian, L., Li, A., Huang, Y., Yu, J., & You, X. (2022). 6G oriented 100 GBE real-time demonstration of Fiber-THz-Fiber seamless communication enabled by photonics. Optical Fiber Communication Conference (OFC) 2022. https://doi.org/10.1364/ofc.2022.m3z.9

[17]. Iezekiel, S. (2022). Photonic synthesis of MM-Wave and THZ signals for 5G and beyond. 2022 3rd URSI Atlantic and Asia Pacific Radio Science Meeting (AT-AP-RASC). https://doi.org/10.23919/at-ap-rasc54737.2022.9814340

[18]. Pandey, G. K., Rao, T., & Mondal, S. (2022). Design and Analysis of Graphene based Octagonal Short-angular Circular Patch MIMO Antenna for Terahertz Communications. 2022 2nd International Conference on Intelligent Technologies (CONIT). https://doi.org/10.1109/conit55038.2022.9847694

[19]. Nikoo, M. S., & Matioli, E. (2023). Electronic metadevices for terahertz applications. Nature, 614(7948), 451–455. https://doi.org/10.1038/s41586-022-05595-z

[20]. Akyildiz, I. F., & Jornet, J. M. (2016). Realizing Ultra-Massive MIMO(1024×1024)communication in the (0.06–10) Terahertz band. Nano Communication Networks, 8, 46–54.

[21]. Do, H., Cho, S., Park, J., Song, H., Lee, N., & Lozano, A. (2021). Terahertz Line-of-Sight MIMO Communication: Theory and practical challenges. IEEE Communications Magazine, 59(3), 104–109. https://doi.org/10.1109/mcom.001.2000714

[22]. Zhang, W., Wang, W., & Zhang, W. (2023). Channel training for RIS-Aided indoor Terahertz MIMO systems. IEEE Wireless Communications Letters, 12(8), 1384–1388. https://doi.org/10.1109/lwc.2023.3275283

[23]. Chen, Y., Tan, J., Hao, M., MacKenzie, R., & Dai, L. (2023). Accurate beam training for RIS-Assisted wideband Terahertz communication. IEEE Transactions on Communications, 71(12), 7425–7440. https://doi.org/10.1109/tcomm.2023.3317291

[24]. Yang, F., Pitchappa, P., & Wang, N. (2022). Terahertz Reconfigurable Intelligent Surfaces (RISS) for 6G communication links. Micromachines, 13(2), 285. https://doi.org/10.3390/mi13020285

[25]. Seeds, A. J., Shams, H., Fice, M. J., & Renaud, C. C. (2015). TeraHertz Photonics for wireless communications. Journal of Lightwave Technology, 33(3), 579–587. https://doi.org/10.1109/jlt.2014.2355137

[26]. Hao-Yu, T., Pan, T., Lei, T., Jian-Hua, Z., & Jing-Suo, H. (2020). Analysis of Short-Distance Terahertz channel characteristics based on channel measurements. Beijing Youdian Xueyuan Xuebao, 43(6), 59. https://doi.org/10.13190/j.jbupt.2020-170

[27]. Han, C., Wang, Y., Li, Y., Chen, Y., Abbasi, N. A., Kürner, T., & Molisch, A. F. (2021). TeraHertz Wireless Channels: a holistic survey on measurement, modeling, and analysis. arXiv (Cornell University). https://doi.org/10.48550/arxiv.2111.04522

[28]. MacCartney, G. R., & Rappaport, T. S. (2017). A flexible Millimeter-Wave channel sounder with absolute timing. IEEE Journal on Selected Areas in Communications, 35(6), 1402–1418. https://doi.org/10.1109/jsac.2017.2687838

[29]. Bensalem, M., & Jukan, A. (2021). Benchmarking machine learning techniques for THZ channel estimation Problems. arXiv (Cornell University). https://doi.org/10.48550/arxiv.2104.08122

[30]. Na, M., Lee, J., Choi, G., Yu, T., Choi, J., Lee, J., & Bahk, S. (2024). Operator’s perspective on 6G: 6G services, vision, and spectrum. IEEE Communications Magazine, 62(8), 178–184. https://doi.org/10.1109/mcom.001.2400060

[31]. Sheikh, F., Zarifeh, N., & Kaiser, T. (2016). Terahertz band: Channel modelling for short‐range wireless communications in the spectral windows. IET Microwaves Antennas & Propagation, 10(13), 1435–1444. https://doi.org/10.1049/iet-map.2016.0022

[32]. Elbir, A. M. (2019). CNN-Based Precoder and combiner design in MMWave MIMO systems. IEEE Communications Letters, 23(7), 1240–1243. https://doi.org/10.1109/lcomm.2019.2915977

Cite this article

Bai,L. (2024). Research on the Application of Terahertz Communication Technology in 5G and Future Networks. Applied and Computational Engineering,99,43-49.

Data availability

The datasets used and/or analyzed during the current study will be available from the authors upon reasonable request.

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Volume title: Proceedings of the 5th International Conference on Signal Processing and Machine Learning

ISBN：978-1-83558-687-7(Print) / 978-1-83558-688-4(Online)

Editor：Stavros Shiaeles

Conference website: https://2025.confspml.org/

Conference date: 12 January 2025

Series: Applied and Computational Engineering

Volume number: Vol.99

ISSN：2755-2721(Print) / 2755-273X(Online)

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