Global Navigation Satellite System (GNSS) constitutes the foremost provider for geo-localization in a growing number of consumer-grade applications and services supporting urban mobility. Therefore, low-cost and ultra-low-cost, embedded GNSS receivers have become ubiquitous in mobile devices such as smartphones and consumer electronics to a large extent. However, limited sky visibility and multipath scattering induced in urban areas hinder positioning and navigation capabilities, thus threatening the quality of position estimates. This work leverages the availability of raw GNSS measurements in ultra-low-cost smartphone chipsets and the ubiquitous connectivity provided by modern, low-latency network infrastructures to enable a Cooperative Positioning (CP) framework. A Proof Of Concept is presented that aims at demonstrating the feasibility of a GNSSonly CP among networked smartphones embedding ultra-lowcost GNSS receivers. The test campaign presented in this study assessed the feasibility of a client-server approach over 4G/LTE network connectivity. Results demonstrated an overall service availability above 80%, and an average accuracy improvement over the 40% w.r.t. to the GNSS standalone solution.

<div>In recent years positioning and navigation capabilities in mobile devices have become essential to the evergrowing number of position-related smart applications. Global Navigation Satellite System (GNSS) constitutes the provider for geo-localization, therefore consumer-grade, embedded GNSS receivers have become ubiquitous in mobile smart devices. Among these, smartphones play a dominant role in enabling such modern services based on position information. However, GNSS positioning shows several weaknesses in urban contexts where mobile smart devices are massively diffused. Indeed, the limited sky visibility and multipath scattering induced by buildings severely threat the quality of the final solution. Two main ingredients can enable innovative collaborative strategies capable to increase the robustness of GNSS navigation: The availability of raw GNSS measurements which have been recently disclosed in ultra-low cost smartphone chipsets and the ubiquitous connectivity provided by modern low-latency, network infrastructures allowing for near-real-time exchange of data. This work presents the architecture of a Proof Of Concept designed to demonstrate the feasibility of a GNSS-only Cooperative Positioning among networked smartphones equipped with GNSS receivers. The test campaign presented in this work assessed the feasibility of the approach over 4G/LTE network connectivity and an average accuracy improvement over the 40%.</div>

<div>In recent years positioning and navigation capabilities in mobile devices have become essential to the evergrowing number of position-related smart applications. Global Navigation Satellite System (GNSS) constitutes the provider for geo-localization, therefore consumer-grade, embedded GNSS receivers have become ubiquitous in mobile smart devices. Among these, smartphones play a dominant role in enabling such modern services based on position information. However, GNSS positioning shows several weaknesses in urban contexts where mobile smart devices are massively diffused. Indeed, the limited sky visibility and multipath scattering induced by buildings severely threat the quality of the final solution. Two main ingredients can enable innovative collaborative strategies capable to increase the robustness of GNSS navigation: The availability of raw GNSS measurements which have been recently disclosed in ultra-low cost smartphone chipsets and the ubiquitous connectivity provided by modern low-latency, network infrastructures allowing for near-real-time exchange of data. This work presents the architecture of a Proof Of Concept designed to demonstrate the feasibility of a GNSS-only Cooperative Positioning among networked smartphones equipped with GNSS receivers. The test campaign presented in this work assessed the feasibility of the approach over 4G/LTE network connectivity and an average accuracy improvement over the 40%.</div>