Frequency transfer through long-distance optical fibre links for relativistic geodesy (A04)

通过长距离光纤链路进行频率传输，用于相对论大地测量 (A04)

• 批准号: 260744428
• 金额: --
• 依托单位: Physikalisch-Technische Bundesanstalt (PTB)
• 依托单位国家: 德国
• 项目类别: Collaborative Research Centres
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/260744428?language=en
• 关键词: Frequency; transfer; through; long; distance

As predicted by Einstein’s general theory of relativity, electromagnetic radiation experiences a frequency shift when travelling through a gravitational field, known as gravitational red shift. As proposed by Vermeer in 1983, and Bjerhammar in 1985, measuring this apparent frequency difference between clocks thus allows us to determine potential (or height) differences between remote sites. The goal of this project is to realise “chronometric levelling” by transferring optical frequencies via optical fibre over large distances, between clocks at different locations. This effort may support future unification of worldwide height reference grids.

正如爱因斯坦的广义相对论所预测的那样，电磁辐射在穿过引力场时会经历频率偏移，称为引力红移。正如Vermeer在1983年和Bjerhammar在1985年提出的那样，测量时钟之间的明显频率差可以让我们确定远程站点之间的潜在（或高度）差异。该项目的目标是通过在不同地点的时钟之间通过光纤远距离传输光学频率来实现“测时调平”。这项工作可能会支持未来全球高度参考网格的统一。