Semantic Fidelity for Intelligent 6G Communication: A Taxonomic Deep Dive into Knowledge-Driven Architectures, Benchmarks, and Challenges
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Abstract
Cognitive-semantic communication encodes task-relevant meaning rather than raw bits, improving 6G spectral efficiency and reducing latency, yet evidence remains fragmented across methods, evaluations, and deployments. This PRISMA-based review screens 782 records (2019-2025) from seven databases, retaining 73 studies organized into five method families: neural semantic codecs, KG-based pipelines, LLM-assisted codecs, cross-modal encoders, and semantic relays. We examine how goal-oriented semantics, knowledge graphs, and LLMs shape representation, compression, and task quality under rate and latency constraints across UAVs, NTNs, ISAC, Metaverse, and IoT. Reported gains include bandwidth reductions of 20-60% over conventional baselines, task accuracy improvements of 8-23 percentage points over bit-level systems, and cross-modal alignment scores above 0.80; however, these gains derive predominantly from AWGN simulations, and robustness under realistic fading, mobility, and adversarial conditions remains the most critical open problem. Gaps include narrow datasets, inconsistent metric definitions, and unaddressed security, privacy, and standardization concerns. Recommendations include shared multimodal datasets with channel traces, standardized robustness protocols, unified metric cards pairing task outcomes with resource costs, edge-friendly split designs, and integrity checks with privacy audits.
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References
- Gündüz, D., Qin, Z., Aguerri, I. E., Dhillon, H. S., Yang, Z., Yener, A., ... & Chae, C. B. (2022). Beyond transmitting bits: Context, semantics, and task-oriented communications. IEEE Journal on Selected Areas in Communications, 41(1), 5-41.
[CrossRef] [Google Scholar] - Xin, G., Fan, P., & Letaief, K. B. (2024). Semantic communication: A survey of its theoretical development. Entropy, 26(2), 102.
[CrossRef] [Google Scholar] - Zhou, H., Deng, Y., Liu, X., Pappas, N., & Nallanathan, A. (2024). Goal-oriented semantic communications for 6G networks. IEEE Internet of Things Magazine, 7(5), 104–110.
[CrossRef] [Google Scholar] - Li, A., Wu, S., Sun, S., & Cao, J. (2024). Goal-oriented tensor: Beyond age of information toward semantics-empowered goal-oriented communications. IEEE Transactions on Communications, 72(12), 7689-7704.
[CrossRef] [Google Scholar] - Strinati, E. C., Di Lorenzo, P., Sciancalepore, V., Aijaz, A., Kountouris, M., Gündüz, D., ... & Li, P. (2024, June). Goal-oriented and semantic communication in 6G AI-native networks: The 6G-GOALS approach. In 2024 Joint European Conference on Networks and Communications & 6G Summit (EuCNC/6G Summit) (pp. 1-6). IEEE.
[CrossRef] [Google Scholar] - Liu, Y., Wang, X., Ning, Z., Zhou, M., Guo, L., & Jedari, B. (2024). A survey on semantic communications: Technologies, solutions, applications and challenges. Digital Communications and Networks, 10(3), 528-545.
[CrossRef] [Google Scholar] - Guo, C., Liu, J., Gao, W., Lu, Z., Li, Y., Wang, C., & Yang, J. (2025). A Large Language Model Driven Knowledge Graph Construction Scheme for Semantic Communication. Applied Sciences, 15(8), 4575.
[CrossRef] [Google Scholar] - Zhou, F., Li, Y., Xu, M., Yuan, L., Wu, Q., Hu, R. Q., & Al-Dhahir, N. (2023). Cognitive semantic communication systems driven by knowledge graph: Principle, implementation, and performance evaluation. IEEE Transactions on Communications, 72(1), 193-208.
[CrossRef] [Google Scholar] - Wu, W., Yao, T., Zhou, F., Qin, Z., Hu, H., & Wu, Q. (2025). Knowledge Graph Enhanced Robust Cognitive Semantic Communication Against Semantic impairment. IEEE Transactions on Communications, 74, 4108-4122.
[CrossRef] [Google Scholar] - Pokhrel, S. R., & Choi, J. (2022). Understand-before-talk (UBT): A semantic communication approach to 6G networks. IEEE Transactions on Vehicular Technology, 72(3), 3544-3556.
[CrossRef] [Google Scholar] - Getu, T. M., Kaddoum, G., & Bennis, M. (2024). A survey on goal-oriented semantic communication: Techniques, challenges, and future directions. IEEE Access, 12, 51223-51274.
[CrossRef] [Google Scholar] - Weng, Z., Qin, Z., & Li, G. Y. (2025). Robust semantic communications for speech transmission. In ICASSP 2025-2025 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) (pp. 1–5). IEEE.
[CrossRef] [Google Scholar] - Sagduyu, Y. E., Erpek, T., Ulukus, S., & Yener, A. (2023). Is semantic communication secure? A tale of multi-domain adversarial attacks. IEEE Communications Magazine, 61(11), 50-55.
[CrossRef] [Google Scholar] - Chen, X., Feng, D., He, Q., Sun, Y., Chen, G., & Xia, X. G. (2024). Content-aware robust semantic transmission of images over wireless channels with GANs. Digital Communications and Networks.
[CrossRef] [Google Scholar] - Lu, Z., Li, R., Lu, K., Chen, X., Hossain, E., Zhao, Z., & Zhang, H. (2023). Semantics-empowered communications: A tutorial-cum-survey. IEEE Communications Surveys & Tutorials, 26(1), 41-79.
[CrossRef] [Google Scholar] - Salehi, S., Erol-Kantarci, M., & Niyato, D. (2025, July). Llm-enabled data transmission in end-to-end semantic communication. In 2025 IEEE Symposium on Computers and Communications (ISCC) (pp. 1-6). IEEE.
[CrossRef] [Google Scholar] - Yang, Z., Chen, M., Li, G., Yang, Y., & Zhang, Z. (2024). Secure semantic communications: Fundamentals and challenges. IEEE network, 38(6), 513–520.
[CrossRef] [Google Scholar] - Wang, Y., Guo, S., Deng, Y., Zhang, H., & Fang, Y. (2024). Privacy-preserving task-oriented semantic communications against model inversion attacks. IEEE Transactions on Wireless Communications, 23(8), 10150-10165.
[CrossRef] [Google Scholar] - Wheeler, D., & Natarajan, B. (2023). Engineering semantic communication: A survey. IEEE Access, 11, 13965–13995.
[CrossRef] [Google Scholar] - Xie, H., Qin, Z., Tao, X., & Letaief, K. B. (2022). Task-oriented multi-user semantic communications. IEEE Journal on Selected Areas in Communications, 40(9), 2584-2597.
[CrossRef] [Google Scholar] - Shannon, C. E. (1948). A mathematical theory of communication. The Bell System Technical Journal, 27(3), 379-423.
[CrossRef] [Google Scholar] - Shao, Y., Cao, Q., & Gündüz, D. (2024). A theory of semantic communication. IEEE Transactions on Mobile Computing, 23(12), 12211-12228.
[CrossRef] [Google Scholar] - Dai, J., Zhang, P., Niu, K., Wang, S., Si, Z., & Qin, X. (2022). Communication beyond transmitting bits: Semantics-guided source and channel coding. IEEE Wireless Communications, 30(4), 170-177.
[CrossRef] [Google Scholar] - Luo, X., Chen, H. H., & Guo, Q. (2022). Semantic communications: Overview, open issues, and future research directions. IEEE Wireless communications, 29(1), 210-219.
[CrossRef] [Google Scholar] - Xie, H., Qin, Z., Li, G. Y., & Juang, B. H. (2021). Deep learning enabled semantic communication systems. IEEE transactions on signal processing, 69, 2663-2675.
[CrossRef] [Google Scholar] - Bourtsoulatze, E., Kurka, D. B., & Gündüz, D. (2019). Deep joint source-channel coding for wireless image transmission. IEEE Transactions on Cognitive Communications and Networking, 5(3), 567-579.
[CrossRef] [Google Scholar] - Qin, Z., Liang, L., Wang, Z., Jin, S., Tao, X., Tong, W., & Li, G. Y. (2024). AI empowered wireless communications: From bits to semantics. Proceedings of the IEEE, 112(7), 621-652.
[CrossRef] [Google Scholar] - Wang, Y., Han, H., Feng, Y., Zheng, J., & Zhang, B. (2025). Semantic communication empowered 6G networks: Techniques, applications, and challenges. IEEE Access, 13, 28293-28314.
[CrossRef] [Google Scholar] - Getu, T. M., Kaddoum, G., & Bennis, M. (2025). Semantic communication: A survey on research landscape, challenges, and future directions. Proceedings of the IEEE, 112(11), 1649-1685.
[CrossRef] [Google Scholar] - Dai, J., Wang, S., Tan, K., Si, Z., Qin, X., Niu, K., & Zhang, P. (2022). Nonlinear transform source-channel coding for semantic communications. IEEE Journal on Selected Areas in Communications, 40(8), 2300-2316.
[CrossRef] [Google Scholar] - Tian, Y., Qin, Z., Lv, G., Jin, Y., Huang, K., & Han, Z. (2026). Large Speech Model Enabled Semantic Communication. IEEE Transactions on Mobile Computing, 25(8), 11600-11614.
[CrossRef] [Google Scholar] - Song, X., Zhou, F., Ding, R., Qu, Z., Li, Y., Wu, Q., & Al-Dhahir, N. (2025). UAV cognitive semantic communications enabled by knowledge graph for robust object detection. IEEE Transactions on Communications, 73(8), 6052-6067.
[CrossRef] [Google Scholar] - Zhu, T., Peng, B., Liang, J., Han, T., Wan, H., Fu, J., & Chen, J. (2024). How to evaluate semantic communications for images with vitscore metric? IEEE Transactions on Cognitive Communications and Networking, 10(5), 1744–1758.
[CrossRef] [Google Scholar] - Jiang, S., Liu, Y., Zhang, Y., Luo, P., Cao, K., Xiong, J., Zhao, H., & Wei, J. (2022). Reliable semantic communication system enabled by knowledge graph. Entropy, 24(6), 846.
[CrossRef] [Google Scholar] - Song, X., Yuan, L., Qu, Z., Zhou, F., Wu, Q., Quek, T. Q., & Hu, R. Q. (2024, June). Knowledge graph driven UAV cognitive semantic communication systems for efficient object detection. In ICC 2024-IEEE International Conference on Communications (pp. 1685-1690). IEEE.
[CrossRef] [Google Scholar] - Peng, Y., Xiang, L., Zhang, B., & Yang, K. (2025). Large Language Model-Driven Distributed Integrated Multimodal Sensing and Semantic Communications. arXiv preprint arXiv:2505.18194.
[CrossRef] [Google Scholar] - Lin, Z., Qu, G., Chen, Q., Chen, X., Chen, Z., & Huang, K. (2025). Pushing large language models to the 6g edge: Vision, challenges, and opportunities. IEEE Communications Magazine, 63(9), 52–59.
[CrossRef] [Google Scholar] - Shi, G., & Xiao, Y. (2024). An Introduction to Semantic Communication and Semantic-Aware Networking Standardization for 6G. GetMobile: Mobile Computing and Communications, 28(3), 14–19.
[CrossRef] [Google Scholar] - Gu, J., Zhang, X., Cui, Q., & Tao, X. (2023, November). Semantic communication for multi-modal data transmission. In 2023 International Conference on Wireless Communications and Signal Processing (WCSP) (pp. 208-213). IEEE.
[CrossRef] [Google Scholar] - Zhang, T., Kishore, V., Wu, F., Weinberger, K. Q., & Artzi, Y. (2019). Bertscore: Evaluating text generation with bert. arXiv preprint arXiv:1904.09675.
[CrossRef] [Google Scholar] - Han, T., Tang, J., Yang, Q., Duan, Y., Zhang, Z., & Shi, Z. (2023, June). Generative model based highly efficient semantic communication approach for image transmission. In ICASSP 2023-2023 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) (pp. 1-5). IEEE.
[CrossRef] [Google Scholar] - Li, A., Wu, S., Meng, S., Lu, R., Sun, S., & Zhang, Q. (2024). Toward goal-oriented semantic communications: New metrics, framework, and open challenges. IEEE Wireless Communications, 31(5), 238-245.
[CrossRef] [Google Scholar] - Guo, S., Wang, Y., Zhang, N., Su, Z., Luan, T. H., Tian, Z., & Shen, X. (2024). A survey on semantic communication networks: Architecture, security, and privacy. IEEE communications surveys & tutorials, 27(5), 2860-2894.
[CrossRef] [Google Scholar] - Kaleem, Z., Orakzai, F. A., Ishaq, W., Latif, K., Zhao, J., & Jamalipour, A. (2024). Emerging trends in UAVs: From placement, semantic communications to generative AI for mission-critical networks. IEEE Transactions on Consumer Electronics, 71(3), 7412-7438.
[CrossRef] [Google Scholar] - Ding, Y., Yang, Z., Pham, Q. V., Hu, Y., Zhang, Z., & Shikh-Bahaei, M. (2023). Distributed machine learning for UAV swarms: Computing, sensing, and semantics. IEEE Internet of Things Journal, 11(5), 7447-7473.
[CrossRef] [Google Scholar] - Zheng, G., Ni, Q., Navaie, K., & Pervaiz, H. (2024). Semantic communication in satellite-borne edge cloud network for computation offloading. IEEE Journal on Selected Areas in Communications, 42(5), 1145-1158.
[CrossRef] [Google Scholar] - Sagduyu, Y. E., Erpek, T., Yener, A., & Ulukus, S. (2024). Will 6G be semantic communications? Opportunities and challenges from task oriented and secure communications to integrated sensing. IEEE Network, 38(6), 72-80.
[CrossRef] [Google Scholar] - Lin, Y., Gao, Z., Du, H., Wang, J., & Zheng, J. (2025). Semantic communication in the metaverse. Wireless Semantic Communications: Concepts, Principles and Challenges, 133-161.
[CrossRef] [Google Scholar] - Shi, G., Xiao, Y., Li, Y., & Xie, X. (2021). From semantic communication to semantic-aware networking: Model, architecture, and open problems. IEEE Communications Magazine, 59(8), 44-50.
[CrossRef] [Google Scholar] - Shi, Y., Zhou, Y., Wen, D., Wu, Y., Jiang, C., & Letaief, K. B. (2023). Task-oriented communications for 6G: Vision, principles, and technologies. IEEE Wireless Communications, 30(3), 78-85.
[CrossRef] [Google Scholar] - Kitchenham, B., & Charters, S. (2007). Guidelines for performing systematic literature reviews in software engineering (Version 2.3). EBSE Technical Report, Keele University and Durham University. https://www.elsevier.com/__data/promis_misc/525444systematicreviewsguide.pdf
[Google Scholar] - Page, M. J., McKenzie, J. E., Bossuyt, P. M., Boutron, I., Hoffmann, T. C., Mulrow, C. D., ... & Moher, D. (2021). The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. BMJ, 372, n71.
[CrossRef] [Google Scholar] - Zhang, B., Qin, Z., & Li, G. Y. (2023). Semantic communications with variable-length coding for extended reality. IEEE Journal of Selected Topics in Signal Processing, 17(5), 1038-1051.
[CrossRef] [Google Scholar] - Sugitha, G., Vasanthi, R., Solairaj, A., & Kalpana, A. (2025). SeCo2: Secure Cognitive Semantic Communication in 6G-IoT Networks Using Key-Policy Attribute-Based Encryption and Elliptic Curve Cryptography. Radioengineering, 34(2).
[CrossRef] [Google Scholar] - Sun, R., Cheng, N., Li, C., Chen, F., & Chen, W. (2024). Knowledge-driven deep learning paradigms for wireless network optimization in 6G. IEEE Network, 38(2), 70–78.
[CrossRef] [Google Scholar] - Wang, Y., Guo, S., Dong, A., & Zhao, H. (2024, October). Benchmarking semantic communications for image transmission over mimo interference channels. In 2024 16th International Conference on Wireless Communications and Signal Processing (WCSP) (pp. 1480-1484). IEEE.
[CrossRef] [Google Scholar] - Xu, J., Wang, X., Chen, L., Lin, L., Hu, J., Khowaja, S. A., & Dev, K. (2025). Fortifying Secure Semantic Communication: A Next-Generation Defense Framework Against Model Inversion and Adversarial Threats. IEEE Wireless Communications, 32(5), 64-71.
[CrossRef] [Google Scholar] - Won, D., Woraphonbenjakul, G., Wondmagegn, A. B., Tran, A. T., Lee, D., Lakew, D. S., & Cho, S. (2024). Resource management, security, and privacy issues in semantic communications: A survey. IEEE Communications Surveys & Tutorials, 27(3), 1758-1797.
[CrossRef] [Google Scholar] - Chaccour, C., Saad, W., Debbah, M., Han, Z., & Poor, H. V. (2024). Less data, more knowledge: Building next-generation semantic communication networks. IEEE Communications Surveys & Tutorials, 27(1), 37-76.
[CrossRef] [Google Scholar] - Guo, Q., Tong, H., Wang, S., Si, P., Zhao, J., & Yin, C. (2026). A secure semantic communication system based on knowledge graph. Journal of Communications and Networks, 28(1), 98-110.
[CrossRef] [Google Scholar] - Hello, N., Di Lorenzo, P., & Strinati, E. C. (2024, September). Semantic communication enhanced by knowledge graph representation learning. In 2024 IEEE 25th International Workshop on Signal Processing Advances in Wireless Communications (SPAWC) (pp. 876-880). IEEE.
[CrossRef] [Google Scholar] - Zhang, P., Xu, W., Gao, H., Niu, K., Xu, X., Qin, X., ... & Zhang, F. (2022). Toward wisdom-evolutionary and primitive-concise 6G: A new paradigm of semantic communication networks. Engineering, 8, 60-73.
[CrossRef] [Google Scholar] - Nguyen, L. X., Raha, A. D., Aung, P. S., Niyato, D., Han, Z., & Hong, C. S. (2025). A contemporary survey on semantic communications: Theory of mind, generative ai, and deep joint source-channel coding. IEEE Communications Surveys & Tutorials, 28, 2377-2417.
[CrossRef] [Google Scholar] - Wei, Z., Qu, H., Wang, Y., Yuan, X., Wu, H., Du, Y., ... & Feng, Z. (2023). Integrated sensing and communication signals toward 5G-A and 6G: A survey. IEEE Internet of Things Journal, 10(13), 11068-11092.
[CrossRef] [Google Scholar] - Guo, J., Chen, H., Song, B., Chi, Y., Yuen, C., Yu, F. R., ... & Niyato, D. (2024). Distributed task-oriented communication networks with multimodal semantic relay and edge intelligence. IEEE Communications Magazine, 62(6), 82-89.
[CrossRef] [Google Scholar] - Giordani, M., & Zorzi, M. (2020). Non-terrestrial networks in the 6G era: Challenges and opportunities. IEEE network, 35(2), 244-251.
[CrossRef] [Google Scholar] - Shao, J., Mao, Y., & Zhang, J. (2021). Learning task-oriented communication for edge inference: An information bottleneck approach. IEEE Journal on Selected Areas in Communications, 40(1), 197-211.
[CrossRef] [Google Scholar] - Shao, J., Zhang, X., & Zhang, J. (2023). Task-oriented communication for edge video analytics. IEEE Transactions on Wireless Communications, 23(5), 4141-4154.
[CrossRef] [Google Scholar] - Sellam, T., Das, D., & Parikh, A. (2020). BLEURT: Learning robust metrics for text generation. In Proceedings of the 58th annual meeting of the association for computational linguistics (pp. 7881–7892).
[CrossRef] [Google Scholar] - Zhang, R., Isola, P., Efros, A. A., Shechtman, E., & Wang, O. (2018, June). The Unreasonable Effectiveness of Deep Features as a Perceptual Metric. In 2018 IEEE/CVF Conference on Computer Vision and Pattern Recognition (pp. 586-595). IEEE.
[CrossRef] [Google Scholar] - Xu, Z., Zhao, Z., & Fingscheidt, T. (2023). Coded speech quality measurement by a non-intrusive PESQ-DNN. IEEE/ACM Transactions on Audio, Speech, and Language Processing, 31, 3404-3417.
[CrossRef] [Google Scholar] - Peer, T., & Gerkmann, T. (2021, September). Intelligibility prediction of speech reconstructed from its magnitude or phase. In Speech Communication; 14th ITG Conference (pp. 1-5). VDE. https://ieeexplore.ieee.org/abstract/document/9657532
[Google Scholar] - Hessel, J., Holtzman, A., Forbes, M., Le Bras, R., & Choi, Y. (2021, November). Clipscore: A reference-free evaluation metric for image captioning. In Proceedings of the 2021 conference on empirical methods in natural language processing (pp. 7514-7528).
[CrossRef] [Google Scholar] - Nan, G., Li, Z., Zhai, J., Cui, Q., Chen, G., Du, X., ... & Quek, T. Q. (2023). Physical-layer adversarial robustness for deep learning-based semantic communications. IEEE Journal on Selected Areas in Communications, 41(8), 2592-2608.
[CrossRef] [Google Scholar] - Yi, P., Cao, Y., Kang, X., & Liang, Y. C. (2023). Deep learning-empowered semantic communication systems with a shared knowledge base. IEEE Transactions on Wireless Communications, 23(6), 6174-6187.
[CrossRef] [Google Scholar] - Bassoli, R., Fitzek, F. H., & Strinati, E. C. (2021). Why do we need 6G?. ITU Journal on Future and Evolving Technologies, 2(6), 1-31.
[CrossRef] [Google Scholar]
Cite This Article
TY - JOUR AU - Singh, Sushil Kumar AU - Ali, Danish AU - Usman, Muhammad Talha AU - Khan, Habib AU - Omer, Muhammad Faizan AU - Zeb, Babar AU - Vavouras, Theodoros AU - Gazis, Alexandros PY - 2026 DA - 2026/09/10 TI - Semantic Fidelity for Intelligent 6G Communication: A Taxonomic Deep Dive into Knowledge-Driven Architectures, Benchmarks, and Challenges JO - ICCK Transactions on Sensing, Communication, and Control T2 - ICCK Transactions on Sensing, Communication, and Control JF - ICCK Transactions on Sensing, Communication, and Control VL - 3 IS - 3 SP - 139 EP - 159 DO - 10.62762/TSCC.2026.286812 UR - https://www.icck.org/article/abs/TSCC.2026.286812 KW - cognitive semantics KW - semantic communication KW - knowledge graphs KW - integrated sensing KW - neural codecs KW - semantic relays KW - goal-oriented communication AB - Cognitive-semantic communication encodes task-relevant meaning rather than raw bits, improving 6G spectral efficiency and reducing latency, yet evidence remains fragmented across methods, evaluations, and deployments. This PRISMA-based review screens 782 records (2019-2025) from seven databases, retaining 73 studies organized into five method families: neural semantic codecs, KG-based pipelines, LLM-assisted codecs, cross-modal encoders, and semantic relays. We examine how goal-oriented semantics, knowledge graphs, and LLMs shape representation, compression, and task quality under rate and latency constraints across UAVs, NTNs, ISAC, Metaverse, and IoT. Reported gains include bandwidth reductions of 20-60% over conventional baselines, task accuracy improvements of 8-23 percentage points over bit-level systems, and cross-modal alignment scores above 0.80; however, these gains derive predominantly from AWGN simulations, and robustness under realistic fading, mobility, and adversarial conditions remains the most critical open problem. Gaps include narrow datasets, inconsistent metric definitions, and unaddressed security, privacy, and standardization concerns. Recommendations include shared multimodal datasets with channel traces, standardized robustness protocols, unified metric cards pairing task outcomes with resource costs, edge-friendly split designs, and integrity checks with privacy audits. SN - 3068-9287 PB - Institute of Central Computation and Knowledge LA - English ER -
@article{Singh2026Semantic,
author = {Sushil Kumar Singh and Danish Ali and Muhammad Talha Usman and Habib Khan and Muhammad Faizan Omer and Babar Zeb and Theodoros Vavouras and Alexandros Gazis},
title = {Semantic Fidelity for Intelligent 6G Communication: A Taxonomic Deep Dive into Knowledge-Driven Architectures, Benchmarks, and Challenges},
journal = {ICCK Transactions on Sensing, Communication, and Control},
year = {2026},
volume = {3},
number = {3},
pages = {139-159},
doi = {10.62762/TSCC.2026.286812},
url = {https://www.icck.org/article/abs/TSCC.2026.286812},
abstract = {Cognitive-semantic communication encodes task-relevant meaning rather than raw bits, improving 6G spectral efficiency and reducing latency, yet evidence remains fragmented across methods, evaluations, and deployments. This PRISMA-based review screens 782 records (2019-2025) from seven databases, retaining 73 studies organized into five method families: neural semantic codecs, KG-based pipelines, LLM-assisted codecs, cross-modal encoders, and semantic relays. We examine how goal-oriented semantics, knowledge graphs, and LLMs shape representation, compression, and task quality under rate and latency constraints across UAVs, NTNs, ISAC, Metaverse, and IoT. Reported gains include bandwidth reductions of 20-60\% over conventional baselines, task accuracy improvements of 8-23 percentage points over bit-level systems, and cross-modal alignment scores above 0.80; however, these gains derive predominantly from AWGN simulations, and robustness under realistic fading, mobility, and adversarial conditions remains the most critical open problem. Gaps include narrow datasets, inconsistent metric definitions, and unaddressed security, privacy, and standardization concerns. Recommendations include shared multimodal datasets with channel traces, standardized robustness protocols, unified metric cards pairing task outcomes with resource costs, edge-friendly split designs, and integrity checks with privacy audits.},
keywords = {cognitive semantics, semantic communication, knowledge graphs, integrated sensing, neural codecs, semantic relays, goal-oriented communication},
issn = {3068-9287},
publisher = {Institute of Central Computation and Knowledge}
}
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