Tuti: An Advanced GNSS-Based Repeater for Seamless Indoor/Outdoor Positioning

Abstract

This paper addresses the limitations of using global navigation satellite systems (GNSS) for positioning in indoor environments, which can experience signal attenuation and blockage from walls. Although there are various indoor positioning techniques available, they typically require additional hardware and cannot provide seamless navigation between indoor and outdoor environments. To overcome these limitations, this paper introduces Tuti, a GNSS-based advanced repeater designed and developed by IGASPIN GmbH. For this purpose, the desired indoor area is virtually divided into small zones, each covered by a directional antenna that transmits Tuti's GNSS signals. This leads the user's calculated position to the approximate actual coordinate in that zone. Tuti's signals are precisely synchronized with GNSS satellites, enabling seamless indoor/outdoor navigation and smooth tracking during the user's transitions between coverage zones. The test results reported in this paper demonstrate how Tuti can provide low-cost indoor positioning with accuracy comparable to outdoor positioning without requiring extra hardware or assistance from the user. Furthermore, it will be discussed that Tuti's capabilities are not limited to indoor applications, such as the transition of cars from the production line in the factory to outside parking slots but also can enhance positioning accuracy in areas with limited visibility to the sky, such as mountainous regions.