Vol 10, No 1 (2019)

Modular, flexible and competitive, Ariane 6 is intended to offer the best space launch solution, by 2020, to commercial and institutional customers. Therefore it can’t anymore rely on legacy inertial reference. Advanced solutions were requested through an open tender conducted by ArianeGroup under European Space Agency (ESA) supervision. SpaceNaute®, the Safran solution based of HRG technology, was then selected against RLG and FOG based solutions proposed by the competitors. This paper describes the trade-off studies conducted to select the proper technology and describe the unique SWaP (Size, Weight and Power) breakthrough of SpaceNaute®, unveils key performance characteristics of the inertial sensors for SpaceNaute® and how HRG benefits are capitalized into the product

A methodology has been developed to construct SBAS ionospheric grid based on the data from ionosphere radio occultation monitoring systems such as COSMIC. This methodology facilitates calculation of vertical delay of GNSS signals on frequency L1 for any geographical location. The corrections are used by a single-frequency receiver for improving the accuracy of position estimation in solving the navigation problem. Using the combination of ionosphere model and the data from radio occultation monitoring systems, it is possible to form real-time corrections on a global scale, and to make their short-term forecasts. The proposed method testing results showed good conformance with the data from vertical sounding stations, and the magnitudes of vertical delays of signal on frequency L1, represented by EGNOS system as differential corrections.

A new continuous-time particle filter algorithm is proposed for solving the problems of nonlinear estimation of signal when describing the mathematical models of an observed object and a measuring system by means of stochastic differential equations. This algorithm can be used in the estimation problems related to navigation data processing. The algorithm verification is presented by example of a navigation system error estimation using geophysical field map data.