5G positioning with software-defined radios

Positioning is a key focus in 5G standardization, starting with 3GPP Release 16. However, most of the effort from the research community and work presented in the technical standardization has been limited mainly to simulation studies. This paper explores the use of software-defined radios (SDRs) platforms for 5G positioning, presenting an overview of the current state-of-the-art and available open-source platforms. Utilizing an advanced SDR-based multi-gNodeBs (gNBs) synchronized testbed, the paper conducts a series of time-based, over-the-air measurements. Results offer insights into the impact of various real-world system parameters, such as the number of gNBs, transmission bandwidth, signal processing techniques, and localization algorithms on positioning accuracy and Time to First Fix (TTFF). These findings provide a pathway for the cost-effective and efficient implementation of high-precision 5G localization systems. The paper contributes to advancing both theoretical understanding and practical applications, serving as a guide for the development of 5G positioning technology.