Examining the pitfalls of Power Examining the pitfalls of Power Line TelecommunicationLine Telecommunication

(PLT)(PLT)

Hans van de Groenendaal

South African Radio League

Back Ground?Back Ground?

Power Line Telecommunication has met Power Line Telecommunication has met with lots of resistance in most parts of the with lots of resistance in most parts of the world.world.

There is very little proof (if any) of There is very little proof (if any) of successful large scale deployment of PLTsuccessful large scale deployment of PLT

Will the draft ICASA PLT regulations fly?Will the draft ICASA PLT regulations fly?

What are the PLT risks?What are the PLT risks?

Currently there are no performance or Currently there are no performance or interference standards- hence the interim interference standards- hence the interim draft regulationsdraft regulations

Power reticulation is of varying standards Power reticulation is of varying standards which is often a major contributory factor which is often a major contributory factor to the HF radio interference problem.to the HF radio interference problem.

USA Installations considered successful USA Installations considered successful are now being challenged in the courtsare now being challenged in the courts

Have Interference problems Have Interference problems been disproved?been disproved?

A recent test carried out by the SABS A recent test carried out by the SABS under the auspices of ICASA at a site in under the auspices of ICASA at a site in Rooiwal showed significant interference Rooiwal showed significant interference on a wide range of HF frequencieson a wide range of HF frequencies

The intention of the tests was to give The intention of the tests was to give ICASA an indication of the risk to the radio ICASA an indication of the risk to the radio frequency spectrum, mainly in the short frequency spectrum, mainly in the short wave spectrum, below 30MHzwave spectrum, below 30MHz

RooiwalRooiwal

RooiwalRooiwal

SARL INTEFERENCE TESTSARL INTEFERENCE TEST

Saturday 22 July 2006 at approx 17:00 Saturday 22 July 2006 at approx 17:00 The radio installed in the vehicle was a The radio installed in the vehicle was a

ICOM 726 connected to a Hustler antenna ICOM 726 connected to a Hustler antenna with 80 and 40 M elements resonated at with 80 and 40 M elements resonated at 3,640 and 7,060 MHz. 3,640 and 7,060 MHz.

The initial observation 3,640 MHz The initial observation 3,640 MHz As the vehicle entered the Township the As the vehicle entered the Township the

interference increased to 9 +20 dBinterference increased to 9 +20 dB Observations were made on the corner of Observations were made on the corner of

4th and 8th Streets and the S meter still 4th and 8th Streets and the S meter still registered 9+20 dB.registered 9+20 dB.    

Cape Town TestCape Town Test

On the request of ICASA a test was On the request of ICASA a test was carried out with Motorola Equipment carried out with Motorola Equipment installed on an underground cable installed on an underground cable reticulationreticulation

Results were encouraging. The full report Results were encouraging. The full report is pendingis pending

Another test using the same equipment is Another test using the same equipment is planned on overhead reticulationplanned on overhead reticulation

Why is HF so important in Why is HF so important in the African Context?the African Context?

The HF spectrum provides long range The HF spectrum provides long range communicationcommunication

In many African Countries broadcast In many African Countries broadcast stations have to use HF frequencies to stations have to use HF frequencies to cover the countrycover the country

Airlines use HF to keep in touch with their Airlines use HF to keep in touch with their aircraft flying over Africaaircraft flying over Africa

Medical emergencies ( Red Cross)Medical emergencies ( Red Cross) Peace keeping operationsPeace keeping operations Maritime emergencies Maritime emergencies Military applicationsMilitary applications Mining operationsMining operations

NEXT STEP FOR PLTNEXT STEP FOR PLT

ICASA has published a set of draft ICASA has published a set of draft regulationsregulations

But do the regulations go far enough to But do the regulations go far enough to protect the HF frequency spectrum?protect the HF frequency spectrum?

Not so according to various Not so according to various submissionssubmissions

Main Points from SARL Main Points from SARL SUBMISSIONSUBMISSION

The FCC did not include the exclusion of The FCC did not include the exclusion of amateur HF frequency bands in their amateur HF frequency bands in their regulations but paid a heavy price with regulations but paid a heavy price with large number of interference complaints large number of interference complaints and on going court action.and on going court action.

The latest is that the courts ruled in The latest is that the courts ruled in favour of the ARRL on two countsfavour of the ARRL on two counts

The Court agreed with the ARRL that the The Court agreed with the ARRL that the FCC had failed to comply with the APA by FCC had failed to comply with the APA by not fully disclosing for public comment the not fully disclosing for public comment the staff studies on which it relied. staff studies on which it relied.

The Court also agreed with the ARRL that The Court also agreed with the ARRL that the Commission erred in not providing a the Commission erred in not providing a reasoned justification for its choice of an reasoned justification for its choice of an extrapolation factor of 40 dB per decade extrapolation factor of 40 dB per decade for Access BPL systems and in offering for Access BPL systems and in offering "no reasoned explanation for its dismissal "no reasoned explanation for its dismissal of empirical data that was submitted at its of empirical data that was submitted at its invitation."invitation."

The FCC did not include the exclusion of The FCC did not include the exclusion of amateur HF frequency bands in their amateur HF frequency bands in their regulations but paid a heavy price with regulations but paid a heavy price with large number of interference complaints large number of interference complaints and on going court action.and on going court action.

It is interesting to note that in the USA, as It is interesting to note that in the USA, as a practical matter, BPL manufacturers a practical matter, BPL manufacturers have had to avoid the ham bands and are have had to avoid the ham bands and are notching the amateur radio frequencies as notching the amateur radio frequencies as a matter of cause. The SARL therefore a matter of cause. The SARL therefore request again that all amateur bands be request again that all amateur bands be included in the table of Frequency Band included in the table of Frequency Band Exclusion.Exclusion.

In draft rule 6.5 a notch depth of 20 dB is In draft rule 6.5 a notch depth of 20 dB is recommended. This has proven to be recommended. This has proven to be inadequate. inadequate.

The state of the art of the technology is The state of the art of the technology is that notch depth is at 35 dB as a that notch depth is at 35 dB as a minimum.  minimum. 

Having a 35 dB requirement would not be Having a 35 dB requirement would not be a major burden on the industry but would a major burden on the industry but would avoid most major interference problems if avoid most major interference problems if coupled with Amateur band exclusions.coupled with Amateur band exclusions.

Complaint – Resolution processesComplaint – Resolution processes The "mutually agreeable schedule” is not The "mutually agreeable schedule” is not

a workable practice and could lead to a workable practice and could lead to extended periods to reach agreement. If extended periods to reach agreement. If the industry has the mechanism to the industry has the mechanism to respond to public-safety complaints within respond to public-safety complaints within 24 hours, there is no reason not to apply 24 hours, there is no reason not to apply that standard to all interference that standard to all interference complaints. complaints.

Is it worth taking the risk?Is it worth taking the risk?

While the PLC interference debate is While the PLC interference debate is ongoing other broadband systems are ongoing other broadband systems are forgoing ahead and are being deployedforgoing ahead and are being deployed HSPA HSPA WiMAX WiMAX WIFI WIFI VSATVSAT

Is there a future for PLT? Is there a future for PLT? As a last mile solution – doubtfulAs a last mile solution – doubtful As an internal broadband distribution medium As an internal broadband distribution medium

– there seems to be some opportunities– there seems to be some opportunities

ConclusionConclusion

The South African Radio League supports The South African Radio League supports technology innovationtechnology innovation

It is the whole essence of the existence of It is the whole essence of the existence of Amateur RadioAmateur Radio

No innovation must be to the detriment of No innovation must be to the detriment of the Radio Spectrum the Radio Spectrum

We have only one such national resourceWe have only one such national resource

Amateur Radio Amateur Radio Communication Communication

Technology in ActionTechnology in Action