7-11 July 2014
Africa/Johannesburg timezone
<a href="http://events.saip.org.za/internalPage.py?pageId=16&confId=34"><font color=#0000ff>SAIP2014 Proceedings published on 17 April 2015</font></a>

Phase Noise Analysis of a 1.712 GHz Clock Signal Transmitted over Optical Fibre for MeerKAT Time and Frequency Reference (TFR)

8 Jul 2014, 17:10
1h 50m
D Ring ground level

D Ring ground level

Board: F.199
Poster Presentation Track F - Applied Physics Poster1


Mr Enoch K. Rotich Kipnoo (Nelson Mandela Metropolitan University)

Apply to be<br> considered for a student <br> &nbsp; award (Yes / No)?


Level for award<br>&nbsp;(Hons, MSc, <br> &nbsp; PhD)?


Main supervisor (name and email)<br>and his / her institution

Prof. Tim Gibbon, Tim.Gibbon@nmmu.ac.za, Nelson Mandela Metropolitan University

Would you like to <br> submit a short paper <br> for the Conference <br> Proceedings (Yes / No)?


Abstract content <br> &nbsp; (Max 300 words)<br><a href="http://events.saip.org.za/getFile.py/access?resId=0&materialId=0&confId=34" target="_blank">Formatting &<br>Special chars</a>

MeerKAT telescope demands highly accurate and stable clock distribution over up to 12 km of optical fibre to remote dishes. The clock is required for digitization of radio astronomy signals. Phase stability is critical both for short term and long term requirements. The long term stability is important for very long baseline interferometry (VLBI) while the short term is vital for digitization process. The short term clock stability also known as clock jitter can be measured by analysing the phase noise performance of a signal. In this work, phase noise measurements were performed on optical transmitters used to distribute the clock signals so as to ascertain their contribution to the overall clock jitter of the system. A directly modulated distributed feedback (DFB) laser was shown to meet the maximum jitter requirement of 130 fs for a 1.712 GHz clock signal transmitted over 25 km of fibre. We further demonstrate that with optimized modulation depth, additional passive optical components in the link do not significantly degrade the phase noise response. Thus, A DFB laser was proven to be a suitable optical source that will meet the performance and link budget requirements for the MeerKAT telescope.

Primary author

Mr Enoch K. Rotich Kipnoo (Nelson Mandela Metropolitan University)


Prof. Andrew Leitch (Nelson Mandela Metropolitan University) Mr Francois Kapp (Square Kilometre Array) Mr Henno Kriel (Square Kilometre Array) Dr Romeo Gamatham (Nelson Mandela Metropolitan University) Mr Sias Malan (Square Kilometre Array) Prof. Tim Gibbon (Nelson Mandela Metropolitan University)

Presentation Materials

There are no materials yet.