Electrical pulse (risetime) intercomparison
Project Description
The project, following on from a EUROMET expert meeting on fast pulses (project No. 544), was discussed at the EUROMET HF Experts Meeting (Paris, Nov 2001). It was agreed that ‘fast pulse’ lies within the remit of the HF Experts Group.
In Europe NPL and PTB have the most accurate facilities and both are keen to proceed with a key comparison. However, other EUROMET labs also expressed an interest in fast pulses at the meeting: SIQ, SP, NMi/VSL, TUBITAK-UME, BNM-LNE, CSIR-NML and CMA.
PTB volunteered a device (Tektronix SD-32 sampling head) and prepared a short technical proposal for the KC. It was proposed the main comparison will start in October 2002. It was also suggested that before October a pilot comparison would be run between PTB and NPL only, to test the travelling behaviour of the standard.
NPL notes the type of device proposed for the KC will affect the participation of labs in addition to NPL and PTB. NPL is contacting all of the interested parties to reach a consensus on a protocol for the KC to try to resolve these issues.
Final Report 2007-04-27
Measurements in this comparison were completed in 2004 and the final report was submitted to the chair of the EUROMET RF Working Group for formal approval on 9th November 2006. This was a bilateral comparison between PTB and NPL. Good agreement was achieved between the two laboratories in the measurements. Both laboratories quoted similar uncertainties and there were no discrepant results. A paper on the comparison was presented at CPEM 2006 and a joint paper has since been published in IEEE Transactions. I&M-56, No2, April 2007, pp 266 - 270.
This comparison originated in a EUROMET experts meeting on fast pulses (project No. 544), and it was initially discussed and proposed at a EUROMET HF Experts Meeting (Paris, Nov 2001) where it was agreed that “fast pulses” lies within the remit of the HF Experts Group. A number of other EUROMET labs also expressed an interest in a fast pulse comparison at the meeting: SIQ, SP, NMi/VSL, TUBITAK-UME, BNM-LNE, CSIR-NML and CMA. However, in Europe, NPL and PTB have the most accurate facilities and it was decided that this bilateral should take place first – followed by a second rise-time comparison for the other Euromet laboratories in which both NPL and PTB should take part.
It is intended that this second rise-time comparison will be discussed at the EUROMET RF sub-field meeting in Delft on 26th April 2007. NPL will be able to co-ordinate the initial stages of this comparison – e.g. to canvas participants, etc - but NPL will not be able to act as pilot laboratory for it.