AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |
Back to Blog
Doppler free12/30/2023 2019) which foresees 24 satellites in medium-earth orbits (MEO, in three orbital planes, similar to the current Galileo system), together with 6 satellites in low-Earth orbit (LEO). One example is the proposed Kepler architecture (Giorgi et al. ![]() 2006), on the other hand, optical clock technologies-in combination with optical inter-satellite links-enable new GNSS architectures. On the one hand, optical clocks could back-up or replace the currently used microwave clocks (Droz et al. Optical clocks surpass the performance of the currently used GNSS microwave clocks by several orders of magnitude. While becoming more and more widespread technology in and outside laboratories on Earth, also space applications-including GNSS-can benefit from the recent advancement of optical technologies. Over the last decades, optical clock technologies evolved, recently demonstrating frequency instabilities at the 10 –18 level for integration times of a few thousand seconds (Ushijima et al. We introduce optical clock technologies for applications in future GNSS and present the current status of our developments of iodine-based optical frequency references. Compact and ruggedized setups have been developed, showing frequency instabilities at the 10 –15 level for averaging times between 1 s and 10,000 s. Optical frequency references based on Doppler-free spectroscopy of molecular iodine are seen as a promising candidate for a future GNSS optical clock. Furthermore, optical clock technologies-in combination with optical inter-satellite links-enable new GNSS architectures, e.g., by synchronization of distant optical frequency references within the constellation using time and frequency transfer techniques. Especially optical clocks could back-up or replace the currently used microwave clocks, having the potential to improve GNSS position determination enabled by their lower frequency instabilities. Future generations of global navigation satellite systems (GNSSs) can benefit from optical technologies.
0 Comments
Read More
Leave a Reply. |