# A Testbed for GNSS-Based Positioning and Navigation Technologies in Smart Cities:
###### Abstract  
In urban contexts, the increasing density of electronic devices equipped with Global Navigation Satellite System (GNSS) receivers and complementary positioning technologies is attracting research and development efforts devoted to an improvement of the quality of life towards the smart city paradigm. Vehicular and pedestrian positioning and navigation capabilities are among the major drivers for innovation in this process. Ultra-low-cost electronics such as smartphones and Internet of Things (IoT) sensors aim at providing accurate and reliable positioning solutions through a set of promising solutions. Among these, snapshot positioning allows to remotely perform the post-processing of GNSS signals in IoT sensor networks while Wi-Fi(tm) ranging and cooperative positioning provide auxiliary anchors of opportunity to enhance indoor/outdoor positioning capabilities. This paper presents an innovative platform to perform a centralised testing and assessment of such positioning and navigation technologies along with a set of results obtained in the context of the European project HANSEL, by relying on current network technologies and infrastructures (i.e., Wi-Fi(tm) and cellular connectivity). GNSS; LTE; smart cities; Wi-Fi(tm); collaborative positioning +
Footnote †: journal: Smart Cities  
0000-0001-5000-5000-5000-5000-5000-5000-5000-5000-50000-5000-5000-50000-5000-5000-50000  
Sustainable development is not achievable without taking social, economic, and environmental issues into account at the same time when innovation is claimed [7]. A sustainable economy enables cities to make long-term investments necessary to build and maintain adequate infrastructure so as to provide effective services, develop an open social environment for citizens, and foster and support business activities, without compromising the natural environment. Information and Communication Technologies (ICTs) is not the only ingredient of a Smart City but it is undoubtedly among the enabling factors. Looking at the city as a complex system, ICTs simplify the management of complexity and allow us to approach sustainable development in an integrated fashion. ICTs allow us to measure and analyze complex phenomena and facilitate short and long-term planning and decision-making in real time. Thus, ICT acts as the foundation of a Smart City. A meaningful use of data requires the existence and development of a large-scale ICT infrastructure in the urban setting. Not only, the design of this infrastructure must itself be intelligent. It is of paramount importance to add intelligence to this system and provide scalability, robustness, and flexibility. In such a Smart City context, a relevant aspect is the provision of location- and navigation-related services for both the users and within the network itself. This appears immediate when applications such as traffic management, access control, geofencing, autonomous mobility, precise positioning, public health and safety, critical infrastructure, or security are among the aims that drive the innovation of modern urban scenarios [8, 9, 10, 11, 12]. It comes naturally that one of the key enablers of such services is the Global Navigation Satellite System (GNSS), through its global coverage and free of charge provision of absolute positioning solutions. Together with the growing adoption and availability of GNSS signals, frequencies, and services, user technologies have evolved and disseminated in a multitude of devices and applications. In parallel to state-of-the art integration of inertial systems, other technologies have continuously emerged and evolved into the Position Navigation and Timing (PNT) Position Time Velocity (PVT) domain, such as Wi-Fi(tm) network and 4G/LTE/5G [13, 14], by increasing even further the possibilities for positioning solutions and the synergies with GNSS in providing enhanced location and navigation capabilities to the users [15].