Precision millimeter-wave time transfer
Abstract
The exceptional level of accuracy and stability of state of the art optical clocks holds great potential to advance capabilities in PNT, advanced communications, arrayed sensing networks, and basic science. However, unlocking this potential necessitates the development of synchronization and time-transfer techniques that can maintain the inherent stability and accuracy of remote optical clocks. GPS and two-way RF links can only provide accuracies at the ~50 ps to 1 ns level, lagging 5 to 6 orders of magnitude behind the inherent accuracy of optical clocks. Although free-space optical two-way time transfer has demonstrated sub-femtosecond accuracy, the use of optical carriers requires strict line-of-sight operation, active tracking control as well as favorable weather conditions, which limits the deployment of this technique in real scenarios. Here we propose the use of mm-wave carriers for two-way time transfer as a trade-off between time accuracy and robustness against poor visibility or weather conditions, while also providing time broadcasting capabilities. A phase-stabilized bidirectional mm-wave frequency transfer link will be established between two sites, and then time information will be transfered via modulation of the mm-wave carrier using a combination of low-jitter electronics and optical modulation techniques. The results of this work will be used to evaluate the feasability of open-air mm-wave link over kilometer distances.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 06, 2025
- Source ID
- FA95502410142
Entities
People
- Scott A. Diddams
Organizations
- Air Force Office of Scientific Research
- Regents of the University of Colorado
- United States Air Force