Prof. Pan Jianwei and his colleagues from the University of Science and Technology of China of the Chinese Academy of Sciences investigated the high-loss free space, high-precision time-frequency dissemination between remote locations, simulating high-precision time-frequency high-orbit satellite-ground links in the channel loss, atmospheric noise, and transmission delay effects
Por: University of Science and Technology of China, Phys News. Acesse aqui a matéria original.
High-precision time-frequency dissemination and comparison techniques apply in all kinds of large-scale precision measurement systems. At present, the international metrology standard systems are at the quantization stage. The frequency standard is at the core of the precision measurement and international metrology systems. Other basic physical quantities except for the amount of matter (mol) are directly or indirectly traced to the frequency. On the other hand, the novel optical frequency standard technologies develop rapidly, whose accuracy is two orders of magnitude better than that of the original second definition frequency standard. Saiba mais...
Imagem: Pixabay/ CC0 Public Domain