English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The disclosed satellite metadata as well as previous estimations using ReviseKinematic Precise Point Positioning (RKPPP) approach with L-band data havealready demonstrated the continuous yaw steering model used by BDS-3 MediumEarth Orbit (MEO) satellites manufactured by China Academy of Space Technology(CAST) in deep eclipse seasons instead of the orbit normal mode. However, theyaw model has not been validated for MEO satellites manufactured by ShanghaiEngineering Center of Microsatellites (SECM), as the horizontal phase centeroffsets (PCO) approaches zeros, similar for BDS-3 Inclined Geostationary Orbit(IGSO) satellites. In this study, the inter-satellite link (ISL) data were usedto estimate the yaw angles of BDS-3 IGSO and MEO satellites with accuracy ofaround 1.49{\deg} to investigate their yaw behaviors, particularly in the deepeclipse seasons. The estimates confirm that the IGSO and MEO satellites fromCAST show the similar yaw behaviors, while the SECM MEO satellites do not fullycomply with the attitude law published by China Satellite Navigation Office(CSNO). The attitude transition postpones from that predicted by CSNO yaw law,and occurs when the yaw angle is less than 5{\deg} and the elevation angle ofthe Sun above the orbital plane (beta angle) crosses 0{\deg}. The transitioncompletes within three minutes with a rate about 0.055{\deg}/s. A model isproposed to predict these behaviors, and the ISL residuals return to normallevels, and became more stable in the adjacent of midnight and noon points.Once the yaw models are used.

Yaw attitudes for BDS-3 IGSO and MEO satellites: estimation, validation and modeling with inter-satellite link observations