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HOME | AMATEUR (HAM) RADIO | BPL WATCH | CLUB STATION - VK7OTC | CONTACTS & QSL | EVENTS & MEETINGS | HISTORY | LINKS | OPTICAL | REPEATERS, BEACONS, IRLP & ECHOLINK | TASMANIA | VK7 AWARDS, CONTESTS & NETS | VK7 REGIONAL NEWS |
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You
may need acrobat
reader to view this type of file Quick Links:
1st Trial: Kirksway Place: 2nd Trial: Mt Nelson: Tolmans Hill:
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Radio and Electronics Association of Southern Tasmanian
Inc.
VK7
(Tasmanian) BPL Watch
The
radio frequency spectrum is an international natural resource.
It is recognized internationally and regulated by the
International Telecommunication Union (ITU)
established by the United Nations. The
International Amateur Radio Union (IARU)
is charged with being the co-ordinating body for all Amateur (or
Ham) Radio interests and spectrum. The Australian member of the
IARU is the Wireless Institute of Australia (WIA)
who acts as the voice for the amateur
interests. There are
approximately 3 million radio amateurs worldwide, 14,500 in
Australia and 600 in Tasmania. What
do radio amateurs “hams” do? Ham
radio is an experimental radio communications service:-
Radio amateurs use leading edge technology Ham’s lead the
way with the use voice over IP (VoIP) technology over the internet
to link repeaters all over the world. Our modes and techniques in
relation to satellite communication, meteor-scatter, tropo-scatter,
earth-moon-earth (Moon Bounce - EME), spread-spectrum, fast-scan
& slow-scan television, high speed packet radio and regularly
talking (not emailing or phoning) people all over the world on a
regular basis. Australian amateurs are credited with the
development of some of the first successful communications
satellites ever launched. There is even a ham station on the
International Space Station. This is hardly out dated technology! Radio amateurs encourage the use of broadband Radio amateurs encourage the use and roll-out of broadband. Hams through the technology they utilise are heavy users of broadband. What Hams are against is the interference causing potential of BPL technology. Radio amateurs do not cause interference Radio amateurs have to operate their equipment within strict limits imposed by the Radiocommunications Licence Condition (Amateur Licence) Determination No. 1 of 1997 and the Radiocommunications Licence Conditions (Apparatus Licence) Determination 2003. We also need to
conform to compulsory electromagnetic radiation (EMR) exposure
limits Radio amateurs carefully match their transmitter to the antenna being used therefore minimising the potential for interference caused by impedance mismatching. If interference does result then radio amateurs take very seriously the resolution of interference complaints with the assistance of the ACMA where necessary. BPL and BPL
operators are not currently subject to EMR/EMC exposure limit or
operational compliance. Hams are licensed users of the spectrum Radio amateurs – “hams” are licensed users of certain parts of the radio spectrum. We have to pass up to three examinations that are regulated by the ACMA and delivered by the WIA to prove we are competent to operate radio equipment in the allocated radio frequency spectrum and within the strict electromagnetic radiation standards. Part
of the spectrum that we are licensed to operate in is the high
frequency (HF 3-30MHz) spectrum that affords long-distance
communications, across the world. It is this spectrum that current
BPL technology uses indiscriminately. As a group,
amateurs only use portions of the spectrum, and as individuals we
use just sections of those portions, at any one time. Whereas, one
BPL location uses all of the HF spectrum and leaves no room for
any other user.
BPL systems are an array of radio transceivers using the powerlines as the transmission medium. These powerlines act in some instances as large antennas with dynamically varying characteristics due to power factor correction and changing power network configuration. BPL operators are not a licensed user of the HF spectrum and yet the technology they are deploying has the potential to cause interference across the whole HF part of the radio frequency spectrum. Who else uses the HF Spectrum:
BPL
(Broadband over Power Lines) or PLT (Power Line
Telecommunications) is a technology to enable the delivery of high
speed data service over the power distribution system. This
technology injects high power, high frequency (typically between 2
and 80MHz) signals over the power distribution network to deliver
high speed data services to homes and businesses. This type of BPL
is termed "Access BPL". There is also "in-house
BPL" which uses building wiring to distribute data
service throughout a building. These systems are currently
incompatible. The issue is that there is a high potential for interference to the high frequency spectrum through the use of this technique. It has been described as "spectrum pollution". This is mainly due to the power distribution network not being an efficient and effective medium for the transmission of high frequency data services. It creates interference to such a level that a HF spectrum user within the trial area cannot hear or transmit a signal. Due to the nature of the high frequency spectrum and its ability to propagate long distances, this interference can propagate around the world. This causes
great concern about this technology not only now but into the
future when the sun-spot cycle improves propagation. The
technology is also prone to interference from other transmitters
in the area. Even
the ACMA in their Access
BPL Guidelines admit: “Use
of the electricity supply network to convey BPL signals will
result in the leakage of radiofrequency emissions. This leakage
has potential to cause interference to radiocommunications
services.” Each time a radio amateur operates, he or she listens first to ensure that their transmission will not interfere with an existing communication path. With the presence of BPL, the amateur is prevented from hearing as to whether another communication already exists or not. Thus he or she is prevented from transmitting anything at all, as well as hearing any reply that may have been possible For more information take a look at: Access
BPL systems cause interference to radiocommunications services,
this is a demonstrable fact:
Access
BPL systems are intended to be “always on”. Thus:
(WIA
Submission
BPL is not an
efficient technology Inductive and capacitive injection of radio frequency on to powerlines originally designed to carry power is a very inefficient process and this means that the signal needs to be injected with high power and boosted every 3-4 power poles and this makes the technology more expensive than other competing technologies. This also means there is a radio frequency transmitter every 3-4 poles that boosts the signal. This also means it is not a cost effective technology in rural areas and relies on densely populated areas (the suburbs) to get any appreciable return on investment. BPL
is an expensive technology The
following table provides an indication of the relativities between
different broadband technology costs:
The State of New Jersey white paper includes additional information from the Shpigler Group report on the deployment cost of competing access technologies: Deployment Cost Per Subscriber:
Source: The Shpigler Group, United Telcom Council Research, Opportunities in Broadband over Power Line, Final Report at 189, (2004) BPL is often touted as the solution for internet service provision in rural areas. However Anthony Good in his FAQ on BPL convincing proves this wrong.
In America & Europe - take a look at: BPL Deployment In Australia - take a look at: ACMA
Australia Trials Summary of overseas trial outcomes: Caslon Analytics Concluded Deployments: Wikipedia Owen Duffy – VK1OD conclusions – comments sourced from the VK1OD website Queanbeyan BPL
trial - VK1OD conclusion: An
amateur station located in the trial precinct would not be safely
able to transmit at all on the 7MHz band because of the high risk
of interference to possibly active stations that would not be
heard through the BPL interference, effectively curtailing all
activity on the band by such a station. Woomera Online BPL Trial Moruya NSW – VK1OD conclusion: An amateur
radio station located in a residential environment where a similar
BPL system was deployed would not be safely able to transmit at
all on the 3.6MHz and 21MHz bands because of the high risk of
interference to possibly active stations that would not be heard
through the BPL interference, effectively curtailing all activity
on the band by such a station. The first BPL trial in April/May 2004 was conducted by Aurora Energy in partnership with Japan’s Mitsubishi Electric and Tasmanian Internet company KeyPoint. The second BPL trial started in late August 2005 and is being conducted by Aurora Energy again in partnership with Japan’s Mitsubishi Electric and Aurora's telco company Tastel. The first trial occurred in April/May 2004. It provided broadband internet to 4 houses (23-29 Kirksway Place and the 1st and 2nd floors of the Aurora office building in 21 Kirksway Place, 7 users all up. Mitsubishi engineers from Japan installed the equipment.
More
comprehensive report on the trial can be found HERE. The second trial commenced on August 29, 2005. The trial will cover 500 homes in Mt Nelson/Tolmans Hill, Burnie and Hobart areas. The trial will run for 9-12 months and the success of the trial will apparently depend on the number of subscribers to the Tastel BPL service. Aurora Energy abandoned
its second trial on 27
November 2007 citing it was not commercially viable in the
current telecommunications climate. What does BPL infrastructure look like? Pole installations around Hobart:
Application Used: SPECTRAN
RF Susceptibility Measurements
If you believe you are being affected by BPL interference we suggest you contact the WIA BPL Interference Advisory Service.
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