Single-Receiver Ambiguity Resolution for Precise Orbit Determination of the Copernicus Sentinel Satellites at the Copernicus POD Service.

Single-receiver GPS ambiguity resolution methods are started to be deployed for precise orbitdetermination (POD) of the Copernicus Sentinel satellites. Previous analyses from othergroups showed the improvement of the orbit results of Sentinel-3A when applyingambiguity-fixing. Prerequisite for these methods are dedicated information and productsproviding the necessary information to perform the single-receiver ambiguity resolution, e.g.,the GPS wide-lane bias product together with the corresponding orbit and clock products.Currently, these necessary inputs are and will be made available from different analysiscentres of the International GNSS Service. The Copernicus Sentinel-1, -2, and -3 orbit products delivered from the Copernicus PODService to the PDGSs (payload data ground segment) of the individual missions are not yetbased on fixed carrier phase ambiguities. Effort is taken to develop and implementcorresponding interfaces and ambiguity fixing strategies. Aim is to be able to deliverambiguity-fixed Sentinel orbits in the operational environment of the Copernicus PODService in future. The impact of the ambiguity-fixed carrier phases on the resulting Copernicus Sentinelorbit products is analysed. Due to the different latencies of the orbital products it hasto be carefully investigated for which product lines dedicated bias products areavailable in time. Backup procedures for the case that the necessary information ismissing have to be developed as well. Additionally, Sentinel-1 and -2 do not provideobservations at multiples of 10 seconds. This might complicate the applicability on thosemissions. This study will give an overview of the work done at the Copernicus POD Service tofollow up recent developments in the frame of single-receiver ambiguity resolution for PODof the Copernicus Sentinel satellites. It also includes the assessment of current and potentialfuture sources of the clock and biases needed. [ABSTRACT FROM AUTHOR]