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Precise Time Reference
| Applications | |
|---|---|
| Title | Precise Time Reference |
| Author(s) | GMV. |
| Level | Medium |
| Year of Publication | 2011 |
Application Architecture
Application Characterization
Application Examples
Network synchronisation for power generation and distribution
The growing integration of networks for energy distribution and the emphasis on energy savings and efficiency require increasingly precise and accurate synchronisation. GNSS can provide the synchronisation to achieve efficient power flow. For example, measurements of perturbations must be time-tagged with errors of less than 0.001 sec. Moreover, the management of high-power generators, such as large turbo gas and large steam turbines, requires strict timing[1].
Electrical energy is not easily stored and, in the case of malfunctions, current or voltage surges propagate along the lines. There is a tremendous potential for cost savings through the reliable remote reading of meters. Surges are sometimes large enough to damage line equipment and cause long interruptions in service. For tracing the origin of the problem and deciding on what action to take, time-tagging the individual events is mandatory. With time synchronisation at the microsecond level, the fault can be located to within 300 m – the distance between power line towers[1].
Communication networks
New digital technologies and value-added time-sensitive services (real-time video, video conferencing, bank-to-bank encrypted exchange) need reliable network architectures (GSM, UMTS, Internet, ATM). Subscriber growth and consumer demand are driving the operators to emphasize quality, reliability and breadth of services. It is therefore imperative that network timing is addressed and that synchronization problems are solved. GNSS can provide high-precision timing and frequency information without the need to invest in expensive atomic clocks[2].
Also satellite-navigation techniques could improve the communication capacity of networks. This is especially relevant for the UMTS third-generation using CDMA techniques. A precise time-synchronisation of the different base stations (the UMTS emitter-antennas) can significantly increase the traffic capability of the system. GNSS can be a reliable tool not only for positioning but also for timing. It will provide the mobile communications operator with a reliable and precise tool, with service guarantee, for increasing their network performance[2].
Data encryption and security of electronic documents
The latest technologies for electronic encryption, signature and time-stamping rely on highly precise time references – at performance levels obtainable only from atomic clocks – so they are not affordable to mass-market users. The spread of the use of GNSS as a timing service enables the secure transmission via inexpensive terminals, thus bringing data security within the reach of us all[3].
These encryption, electronic signatures and time-stamping technologies can be used for securing and authenticate electronic documentation that have become an effective alternative to paper. Many applications for electronic documentation can be enabled by the use of GNSS technology for encryption, electronic signature and time-stamping[3]. Such approach is already being used in the financial sector where security, data integrity, authenticity and confidentiality depend on the accurate time stamps that can be enabled by GNSS[4]
Notes
References
- ^ a b Galileo Application Sheet - Energy Applications, ESA and European Commission, June 2002
- ^ a b Galileo Application Sheet - Telecommunications Applications, ESA and European Commission, June 2002
- ^ a b Galileo Application Sheet - Finance, Banking, Insurance Applications, ESA and European Commission, June 2002
- ^ Europe’s Satellite Navigation Programmes - Galileo and EGNOS, GSA, 2008