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With great potential for being applied to Internet of Things (IoT) applications, the concept of cloud-based Snapshot Real Time Kinematics (SRTK) was proposed and its feasibility under zero-baseline configuration was confirmed recently by the authors. This article first introduces the general workflow of the SRTK engine, as well as a discussion on the challenges of achieving an SRTK fix using actual snapshot data. This work also describes a novel solution to ensure a nanosecond level absolute timing accuracy in order to compute highly precise satellite coordinates, which is required for SRTK. Parameters such as signal bandwidth, integration time and baseline distances have an impact on the SRTK performance. To characterize this impact, different combinations of these settings are analyzed through experimental tests. The results show that the use of higher signal bandwidths and longer integration times result in higher SRTK fix rates, while the more significant impact on the performance comes from the baseline distance. The results also show that the SRTK fix rate can reach more than 93% by using snapshots with a data size as small as 255 kB. The positioning accuracy is at centimeter level when phase ambiguities are resolved at a baseline distance less or equal to 15 km., This research was funded by Albora Technologies and Universitat Politècnica de Catalunya with industrial PhD grant number DI 082 from the Generalitat de Catalunya; This research was partially funded by the Spanish Ministry of Science and Innovation project RTI2018-094295-B-I00. P.C. has been partially supported by the NSF under Awards CNS-1815349 and ECCS-1845833, Peer Reviewed, Postprint (published version)

With snapshot positioning becoming popular for various applications, the present contribution focuses on the feasibility of achieving Real Time Kinematics (RTK) positioning using snapshot data, i.e. a very brief interval of the received satellite signal. This method is termed as Snapshot RTK (SRTK). We first introduce the general workflow of snapshot positioning and the SRTK engine functioning blocks. Their differences from traditional receivers and challenges brought by the short duration of data are explained. Since a major difference of this positioning method is the generation of code and carrier-phase GNSS observables, we go through this procedure in details. In order to explore the feasibility of achieving RTK under different scenarios, the rate of Integer Ambiguity Resolution (IAR) is assessed by using snapshot measurements generated with different integration times and signal bandwidths under zero-baseline configuration. Under these assumptions, the key factor that influences the RTK fix rate is the code measurement noise. Double Difference (DD) code measurement errors are evaluated and plotted together with the resulting IAR fix rates in order to find the relationship between them. The performance of using multi-constellation and multi-frequency signals is tested as well. The fix rate can reach 100% when multiple constellations are used. The achieved positioning accuracy is shown to be less than 5 mm in horizontal domain when IAR is achieved successfully. Finally, some conclusions and thoughts about future research steps on SRTK are given., The author would like to acknowledge Albora Technologies for the technical support during the whole course of this research, including collection of raw data and developments of related software and libraries. The authors would like to thank Everis Aeroespacial y Defensa, S.L.U. for lending the Septentrio base station receiver for this research. The research reported in this paper has been partially supported by the Doctorat Industrial Grant 2018 DI 082 from the Generalitat de Catalunya, and the Spanish Ministry of Science, Innovation and Universities project RTI2018- 094295-B-I00. P. Closas was partially supported by the National Science Foundation under Awards CNS-1815349 and ECCS-1845833., Peer Reviewed, Postprint (published version)