Open Access iconOpen Access



A Survey on Technologies and Challenges of LTE-U

Tong Gan1, Shi-You Wang1, Qiang Ma1, Yi-Dong Jia2,*, Yun-Yun Ma3

1 Beijing Metro Consultancy Corporation Ltd., Beijing, 100071, China
2 School of Computer and Communication Engineering, University of Science and Technology Beijing, Beijing, 100083, China
3 School of Electronic Electrical and Systems Engineering, University of Birmingham, Birmingham, B15 2TT, United Kingdom

* Corresponding Author: Yi-Dong Jia. Email: email

Computer Systems Science and Engineering 2022, 41(1), 321-337.


The rapid growth of mobile data traffic has caused great pressure on the limited spectrum resources, and there must be some better methods to deal with this problem. The innovative technology of Long-Term Evolution (LTE) using the unlicensed spectrum, known as LTE-Unlicensed (LTE-U), has been proposed to effectively alleviate the shortage of authorized band resources. LTE-U has explored a lot of potential capacity in mobile communication systems with limited authorized spectrum resources, and improved the spectrum utilization of unauthorized frequency bands. However, LTE-U is still facing challenges in its application. In this paper, we summarize the key features of LTE-U and the coexistence of LTE-U with Wi-Fi in the unlicensed Spectrum. We analyze the key technologies (including carrier aggregation, HARQ, interference cancelation, and centralized scheduling), the operating modes and deployment scenarios (including carrier aggregation LTE-U, duty cycle LTE-U, and standalone LTE-U), and the advantages (including anchored LTE-U and Standalone LTE-U scenarios), as well as main technical challenges. We then address the different management mechanisms of LTE-U and Wi-Fi (including the differences between the MAC layer and physical layer), the types of coexistence technology classification (including channel separation and channel sharing technologies), and directions for future work. We hope that this comprehensive survey spurs further research in this promising area.


Cite This Article

APA Style
Gan, T., Wang, S., Ma, Q., Jia, Y., Ma, Y. (2022). A survey on technologies and challenges of LTE-U. Computer Systems Science and Engineering, 41(1), 321-337.
Vancouver Style
Gan T, Wang S, Ma Q, Jia Y, Ma Y. A survey on technologies and challenges of LTE-U. Comput Syst Sci Eng. 2022;41(1):321-337
IEEE Style
T. Gan, S. Wang, Q. Ma, Y. Jia, and Y. Ma "A Survey on Technologies and Challenges of LTE-U," Comput. Syst. Sci. Eng., vol. 41, no. 1, pp. 321-337. 2022.

cc This work is licensed under a Creative Commons Attribution 4.0 International License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
  • 1452


  • 839


  • 0


Related articles

Share Link