Sparks fly over power line Internet trials
- 03 February, 2005 15:22
Knocking an aeroplane out of the sky by simply using an ultra-fast Internet connection is closer to fact than fantasy, say opponents of a new Broadband over Power Lines (BPL) technology.
While the prospect of broadband Internet access at 100 times current speeds is exciting Web surfers, critics say the radio interference it causes poses a serious threat to radio networks, including those used by air traffic controllers.
BPL, also known as Power Line Communications (PLC), can transmit data at 200Mbps by utilising normal electrical power lines. Users of the service would plug their broadband modem into a normal household power point.
The technology was given a public boost when NSW energy provider EnergyAustralia announced that it had completed a successful trial of BPL in Newcastle at the end of last year. Other recent trials have occurred in Queanbeyan, by Country Energy, and also one in Tasmania by Aurora Energy.
However, a range of services will be adversely affected by BPL, according to Martin Howells, the NSW State Coordinator for A.C.R.E.M. (Australian Citizens Radio Emergency Monitors).
Howells said AM broadcast radio, amateur radio, HF maritime radio, HF aircraft frequencies, RFDS, School of the Air, 4WD safety and emergency networks, SES and Police HF radio networks, and various other HF radio users and emergency services were all prone to interference by the technology.
Glenn Dunstan, a consulting engineer at Densham & Associates, said the nature of BPL meant it would always create serious side effects.
"Tons of documents prove without a doubt that it does not work," he said. "It [power lines] is designed to carry AC voltage, not radio signals."
From a technical viewpoint, Howell's said BPL technology utilised radio frequencies commonly between 3-30MHz to deliver the broadband signals (it is believed the Newcastle trial used up to 80MHz).
"Power lines tend to radiate the HF frequencies just like a giant 'long-wire' antenna," he said. "It is impossible for the BPL provider to filter all HF frequencies, as this would basically kill the technology, so obviously there is going to be some frequencies radiated from the power lines to be received by nearby receivers.
"Just ask any radio operator about the interference that can be radiated from a faulty/dirty power line insulator -- these can cause problems for hundreds of metres, so what kind of problems do we expect from an actual radio frequency?"
Dunstan labeled proponents of BPL as the modern version of carpet baggers: "They know it causes interference."
Both Country Energy and EnergyAustralia were contacted for further information on their trials but did not respond to requests at the time of this post.
Bring on the trials
Telco analyst Paul Budde from Budde.com has kept a close eye on the BPL technology and has pushed for trials to be undertaken.
According to Budde, BPL is a niche market technology "with perhaps a 5-10 per cent penetration" of such lines in households.
"I honestly don't see a major problem. Let's go into a few commercial trials, actively involve the local radio communities in these trials, let them have a say about potential problem areas, see if we can solve the problems and take it from there."
Budde believes that if there were such alarming levels of interference, organisations such as the FCC in the USA and the EU would not be so positive about this technology.
"Let's have a serious look at it in a life situation, but let us work together not against each other as that would not be very fruitful," Budde said.
Howells believes the trials will yield answers already known: "It has already been stated, both overseas and in Australia, that BPL technology does not offer the fantastic 'all wonderful' technology that it is often hyped up to be."
BPL providers are subject to the law, namely, the offence provisions of the Radiocommunications Act 1992 that deals with interference to radiocommunications.
Additionally, the Wireless Institute of Australia, which represents the interests of licensed radio amateurs in Australia, points out that Australia is a signatory to treaties that commit it to actions to ensure the effective operation of radiocommunications systems.
A report released by WIA in December states: "The Constitution of the International Telecommunications Union is the basic instrument of the Union. The Annex to the Constitution defines certain terms used in the Constitution, the Convention and the Administrative Regulations, the Radio Regulations being the relevant Administrative Regulations, and together all being a treaty to which Australia is party".
It says among the terms defined by the treaty is "harmful interference".
Ultimately the fate of BPL technology rests with the ACA, which acts as the spectrum manager. It has already commenced a comprehensive examination of the communications regulatory issues associated with BPL. The examination so far has involved consultation with relevant stakeholders, with a BPL discussion paper set for public and stakeholder comment early this year.
For Howells, the ACA need not waste its time.
He says future broadband access will be provided by upcoming technology such as WiMax, an implementation of the IEEE 802.16 standard which can transmit a signal as far as 50Kms and at 75Mbs.
"In light of these admissions then one must indeed ask the sense in spending millions of dollars to invest in a technology that has already been proven to cause significant harmful interference to HF radio services, when more appropriate technology is obviously available," he said.