Powerline internet trials in Ireland


The trials are over and the results are in.

During the trials I did some ingress tests with the ESB.

The ESB published a powerpoint presentation on the PLT trials here

Here is a Copy of my ingress report as submitted to the ESB shortly after the ingress tests

The Irish Powerline internet trials have begun in a Town called Tuam in North Co, Galway.

On the 7th of April 2004 I visited the trial area.

It seems that the laws of physics apply to powerlines in Ireland too, Very high levels of interference to HF radio was found in the trial areas.

The system used by the ESB in the trial area is an OFDM type system with discreet carriers approximately every  1.1 Khz and is identical in characteristics to the system in the ARRL trial area #4
video footage of the ARRL monitoring efforts is available here

This may point to it being a DS2 system or a system using the DS2 chipset.
More video and audio footage of systems though to be using the DS2 chipset can be seen on the Spanish national society's PLC page http://www.ure.es/plc/

Both the ARRL and Spanish footage show systems with significant amounts of Internet traffic. The Tuam system seemed to have little or no traffic on it during my visit. Perhaps the user trials have not yet begun? (See Current situation)

In the areas where I could detect significant levels of PLC signals the following frequency ranges were in use.

Location 1, Close to the ESB offices, next to a housing estate

18880 - 22745 Khz. Signals in the 15m band and the broadcast band starting at 21450 Khz were up to s9+60dB and never went below s9 at any of the carrier frequencies. Several very strong broadcast stations were audible but in all cases the interference to reception was severe,  I followed this system along the lines into town. Reception was on a vertical mobile whip
Here is a clip (1.6 MB) of interference to the 15m amateur band at this location. All clips are in AVI format.

2720 to 5870 Khz, Signals in the 80m band were in excess of s9, up to s9+20dB or so as received on an inefficient vertical mobile whip. It was impossible to hear any amateur stations above the noise.
Here is a clip (915 KB) of interference to the 80m amateur band at this location.

Location 2, In the cathedral car park close to the cathedral
The range occupied here is 7940 - 11600 Khz, in the Amateur band it was between s9 and s9+20dB. One strong amateur station detectable through the noise, broadcast reception was possible for the stronger broadcast stations but you could hear the PLT system in the background on even the strongest stations. Reception was on a vertical mobile whip
Here is a clip (680 KB) showing the interference to the 30m amateur band at this location.

Current Situation:

Contact with the ESB indicated that the internet access trials have not yet begun and that the PLC equipment had only been turned on for some system tests. The ESB did confirm use of the frequency ranges given above
A check with a receiver on 16th April 2004 confirms that the system is currently off. We can expect the internet access part of the trials to begin in the next couple of months.

You can find out more about the impact of PLT on HF radio on the following web sites

The ARRL have a PLT page here
The RSGB have some information on PLT here
The BBC have prepared several reports on the impact of PLT on HF broadcasting
The effects of power-line telecommunications on broadcast reception: brief trial in Crieff
Cumulative effects of distributed interferers
Emission limits A new proposal based on a limited increase in the noise floor
How best to protect radio services as intended?
AM broadcasting and emissions from xDSL/PLT/etc

Here is the submission I made to the European commission in relation to PLT last September, it's a 145 KB adobe acrobat file. All the submissions are available on linehere

Peter Cochrane has this to say on the subject of PLT

Here (290KB PDF file) is an interesting economic analysis of the financial viability of PLT done by Carnegie Mellon University in the US, it's fairly full of economist speak but if true points to the financial viability of PLT for the operators being marginal to say the least.

The national society representing Amateur radio in Ireland is theIRTS ( Irish radio transmitters society )

This page is at a very preliminary stage of construction, please feel free to contact me with corrections and suggestions for improvement.
Please check back often for updates

I am Brendan Minish, EI6IZ and I can be contacted by E-mail ei6iz@oceanfree.net