Method and apparatus for synchronizing clocks underwater using light and sound
US9645272B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 2, 2015 |
| Grant date | May 9, 2017 |
| Priority date | — |
| Expiry date | Jan 2, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B13/02
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Methods and systems for synchronizing clocks used in underwater devices is described. All clocks have some drift due to frequency accuracy and this disclosure provides a method for periodically synchronizing clocks to an accurate master clock to remove long term drift. A synchronization device can use an accurate clock and hardware to transmit both a sound wave and light pulse at the same point in time. Remote slave clocks can detect the light first, and later the sound, allowing them to calculate the distance the pulse had to travel. The clocks can then synchronize their time to the master clock canceling out any drift. The synchronization device can be packaged in a waterproof housing and can be moved around on a periodic basis between the clock on an underwater robot or any other means.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.