Accurate localization and situational awareness are increasingly essential for emerging technologies such as autonomous vehicles, including aerial, smart transportation and industrial systems, intelligent radio resource management, etc. In her doctoral research at Tampere University, MSc (Tech) Elizaveta Rastorgueva-Foi developed novel techniques that enable 5G and beyond networks operating in the millimeter-wave bands – corresponding to the extremely high frequency range, namely, 30–300 GHz – to perform precise user positioning and dynamic mapping of the environment without diverting considerable resources from the communications operations.
“Traditionally, wireless networks were designed and optimised for communication purposes, but this thesis expands their role by adapting the existing reference signals for extracting spatial information without needing additional infrastructure,” Rastorgueva-Foi says.
The thesis contributes to channel estimation as well as positioning and mapping
The end-to-end processing chain starts from the raw radio signals, which are used to obtain the spatial parameters of the signal propagation (so-called channel parameters), and a subsequent position estimation and/or tracking.
“One of the innovations of the thesis is a cascaded estimation framework that fuses strength measurements of focused, narrow signals with a tracking algorithm, achieving accurate positioning in industrial as well as in urban settings,” Rastorgueva-Foi explains.
Additionally, the thesis introduces methods that allow a mobile device to independently track walls and obstacles indoors using only its own uplink signal – a significant step towards enabling self-navigation without external sensors. The sensing of the environment takes an advantage of the phenomenon called multipath propagation, happening when multiple copies of a transmitted signal reflected from the surrounding objects are captured by the receiver. Being a nuisance for communication, multipath propagation is a real gold mine for sensing: it allows to build a situational map of the environment while assisting with localization of the user at the same time.
The results were validated with both simulations and real-life measurements, and the proposed techniques are compatible with commercial-off-the-shelf (COTS) devices operating in millimeter-wave bands. The outcomes offer valuable insights for the future integration of joint communication and sensing (JCAS) into 5G and 6G networks.
Public defence on Friday 30 May
The doctoral dissertation of MSc (Tech) Elizaveta Rastorgueva-Foi in the field of Electrical Engineering titled End-to-End Positioning and Mapping in Millimeter-Wave Networks: From Physical Signals to Situational Awareness will be publicly examined at the Faculty of Information Technology and Communication Sciences at Tampere University at 12 o’clock on Friday 30 May 2025 at Hervanta campus, Rakennustalo, in the auditorium RG202 (Korkeakoulunkatu 5, Tampere). The Opponent will be Prof. Nandana Rajatheva, University of Oulu. The Custos will be Prof. Mikko Valkama from the Faculty of Information Technology and Communication Sciences.
The doctoral dissertation is available online.
The public defence can be followed via remote connection.