Localization in Cellular and Heterogeneous Networks for 5G and Beyond: A Review


  • Antoni Ivanov Faculty of Telecommunications, Technical University of Sofia, bul. Kl. Ohridski 8, Sofia 1000, Bulgaria
  • Desislava Koshnicharova Faculty of Telecommunications, Technical University of Sofia, bul. Kl. Ohridski 8, Sofia 1000, Bulgaria
  • Krasimir Tonchev Faculty of Telecommunications, Technical University of Sofia, bul. Kl. Ohridski 8, Sofia 1000, Bulgaria
  • Vladimir Poulkov Faculty of Telecommunications, Technical University of Sofia, bul. Kl. Ohridski 8, Sofia 1000, Bulgaria




5G, cellular networks, fingerprinting, Het-Net, localization, positioning, triangulation, trilateration, wireless networks


Localization in modern and future wireless networks has been established as an important field of research work due to the requirements of location-based applications and services with variety of accuracy requirements. These are driven by the strong heterogeneity in terms of processing power, size and range of the nodes in beyond Fifth Generation (5G) telecommunications. Thus, localization methods in cellular and heterogeneous networks (Het-Nets) diversify in their application scenario (terrestrial and based on aerial platforms) and bands (licensed and unlicensed). They are categorized, according to the methodology used to perform the positioning, into three groups – fingerprinting (learning-based location estimation), trilateration and triangulation (distance or angular based), and hybrid (combining two geometric features of the received signals) methods. For each category, a summary of the methods’ design features and achieved accuracy is presented in tabular form. On the basis of the review, directions for future research are outlined, that will facilitate the further advancements in the design and application of localization methods for wireless communications.


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Author Biographies

Antoni Ivanov, Faculty of Telecommunications, Technical University of Sofia, bul. Kl. Ohridski 8, Sofia 1000, Bulgaria

Antoni Ivanov received the PhD degree in Communication Networks and Systems from the Technical University of Sofia (TUS), Bulgaria. He holds a Master degree in Innovative Communication Technologies and Entrepreneurship from TUS, and Aalborg University, Denmark in 2016. He is currently a Postdoctoral researcher at the “Teleinfrastructure Lab”, Faculty of Telecommunications, TUS. His research interests include cognitive radio networks, adaptive algorithms for dynamic spectrum access, deep learning-based solutions for cognitive radio applications, volumetric spectrum occupancy assessment, and graph signal processing for resource allocation in current and future wireless networks.

Desislava Koshnicharova, Faculty of Telecommunications, Technical University of Sofia, bul. Kl. Ohridski 8, Sofia 1000, Bulgaria

Desislava Koshnicharova is PhD student at the Faculty of Telecommunications of Technical University of Sofia, Bulgaria. She has received her BSc and MSc degrees in Telecommunications from the Technical University of Sofia, Bulgaria, in 2013 and 2015, respectively, graduating both degrees with highest performance records. She had been a member of the Math Team of the Technical University of Sofia and receiving awards from various mathematical competitions. He current research interests in the field of telecommunications are related to resource management, crowd management, user Localization and Open Radio Access Networks.

Krasimir Tonchev, Faculty of Telecommunications, Technical University of Sofia, bul. Kl. Ohridski 8, Sofia 1000, Bulgaria

Krasimir Tonchev is a senior researcher leading the research activities at the “Teleinfrastructure Lab”, Faculty of Telecommunications, Technical University of Sofia, Sofia, Bulgaria. His research interests include Model Based Machine Learning, Bayesian data analysis and modelling, Neural Networks with applicatoins in Computer Vision and data analysis. He has also implemented many commercial projects including photogrammetry, object detection and tracking using thermal vision, dynamic system modeling and image processing for embedded systems.

Vladimir Poulkov, Faculty of Telecommunications, Technical University of Sofia, bul. Kl. Ohridski 8, Sofia 1000, Bulgaria

Vladimir Poulkov has received the M.Sc. and Ph.D. degrees from the Technical University of Sofia (TUS), Sofia, Bulgaria. He has more than 30 years of teaching, research, and industrial experience in the field of Telecommunications. He has successfully managed numerous industrial, engineering, R&D and educational projects. He has been Dean of the Faculty of the Telecommunications at TUS and Vice Chairman of the General Assembly of the European Telecommunications Standardization Institute (ETSI). Currently the Head of the “Teleinfrastructure” R&D Laboratory at TUS and Chairman of Cluster for Digital Transformation and Innovation, Bulgaria. He is Fellow of the European Alliance for Innovation; Senior IEEE Member. He has authored many scientific publications and is tutoring BSc, MSc, and PhD courses in the field of Information Transmission Theory and Wireless Access Networks.


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