UPLC "sets record straight" on BPL

It seems as though the signature of BPL signals is changing as we discuss them. There appears to be a new 10KHz spacing variant, and the Homeplug people have specified a new variant with a probable spacing of 200KHz. Then there are the various other DSS methods that are too random to characterize other than as severely increase noise floor.

To adequately remove a BPL signal by the level of signal processing suggested by Chip would require a very precise knowledge of the signal to be removed. This will be difficult to obtain because the data imposed into the signal will modify its character and because the BPL providers are and will be very unwilling to release that level of information about their systems for security reasons.

Remember when designing for BPL signal removal, there is no standard for any modulation technique and no standard modulation technique. This presents a very large number of possible signals to cancel if only one is present. In the case of more than one, it becomes an exercise of the reader.

David

 

You're absolutely right, I was out of line, and I've edited my previous post on page 18 to correct that.  I wrote the out of line post because I wanted to try and tell Ed (and others) that what we need is for knowledgable people such as himself, to look ahead, study the problem and work for a solution, not simply state "it can't be done", and out of frustration I went too far.

Ed probably has more knowledge about RFI and radio in general in his little fingernail than most of us do in our whole bodies, I'm aware of that...that's why the attitude, "If it were possible, we'd be doing it" drives me crazy.  If they take the attitude, "worked on it, couldn't solve it, can't be done, period", then we truly are in trouble. Minds such as theirs will solve this problem if they continue to work on it. Every day discoveries are made in all fields that we didn't know about yesterday.  If people like Ed and David and other knowledgable people continue to study this problem, I think they'll come up with a solution.  They are our only hope in this situation. No, I don't believe I personally have the knowledge and ability to do it myself but I don't believe that makes it wrong for me to try to encourage those who have the skills to solve the problem, which is all I've been trying to do here.  Granted, I admit that last post was a bit beyond encouraging..... won't happen again.

By the way, K6UEY, since you mentioned me being licensed "in the '70's", I was first licensed in the year 1970, as WN7OQX.

73,
Jim
XE1/K7JAZ

 

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (K7JAZ @ June 28 2004,03:17)</td></tr><tr><td id="QUOTE"></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (W1RFI @ June 29 2004,00:20)</td></tr><tr><td id="QUOTE">"Don't you think that if it could be done, we would be using those techniques right now..."

"Could you at least post a block diagram or a flow chart of the techniques that could do that?  Or are you  another one of those that says it can be done, but doesn't know just how?"

"Or is this one of those do as you say, not do as you do sort of things?"


Ed[/QUOTE]<span id='postcolor'>
Well now I'm really amazed.  The head of the ARRL Lab says "if it could be done, we'd be doing it".  

We didn't come by our present technology all at once.

All I've been trying to say is, just because we have a million and one reasons why it can't be done today doesn't mean it's impossible and won't be done one day soon.   I can't believe this is such an abstract idea and so hard for some to swallow, and getting the snide comments as in the above quote.  


Edited by K7JAZ  [/QUOTE]<span id='postcolor'>
Impossible? I think that few things are.

Practical? IMHO, not at all. BPL signals can range as much as 70 dB greater than the noise floor of amateur stations. In a narrowband system, BPL modulation is an unknown, because one has access to only part of the inforamtion being sent on the channel, so from any way of trying to filter it, it is noise. BPL systems have multiple emitters, radiated from multiple part of the power line, at unpredictable time and phase relationships.

IMHO, the present state of the art does not come close to being able to address this. Even if entirely new filtering technologies are developed that can get the 70 dB Chip promised us, those who say that amateur radio must learn to live with this level of interference are simply being unrealistic. If BPL is deployed, this pie-in-the sky "solution" will not come in time to prevent severe interference to any spectrum BPL uses.

If anyone does want to support the idea that we should live with BPL interference because someone may invent a filtering technique that is not practical for any radio that hams own at this time, I will not agree with them that they have found a solution to BPL interference.

If someone wants to say that someday, someone may invent a new filtering technique that can do this, I will agree that someday someone might.

73,
Ed Hare, W1RFI

 

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (N4LI @ June 23 2004,07:32)</td></tr><tr><td id="QUOTE">Never mind this "armchair amateur" also has a law license and can take the utlility to federal court.

Sorry... I was ranting.  I really hate bad legal writing.[/QUOTE]<span id='postcolor'>
Well, i'm glad someone else thought this read like a third grade term paper. And not to mention it's clearly sarcastic and arrogant tone.

Hope the intended audience has a brain in their head to get their real message

 

OK Ed, I understand where you're coming from now. Thanks for your last post.

73,
Jim
XE1/K7JAZ

 

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (K7JAZ @ June 28 2004,13:48)</td></tr><tr><td id="QUOTE">OK Ed, I understand where you're coming from now.  Thanks for your last post.

73,
Jim
XE1/K7JAZ[/QUOTE]<span id='postcolor'>
Good. There are enough disagreements in life that we don't have to make up ones that don't have to be there.

But I was serious about the fact that if it were possible to copy signals 70 dB below other signals, it would be worth doing right now. At least in the sense that Chip is discussing, virtually all man-made noise is deterministic, so if he is right, we could use the techniques he believes will work to lower our noise floors by 70 dB. In fact, it could be argued that if these techniques to filter out noise exist, they should be applied to the BPL signal to allow it to operate 70 dB below the present levels of man-made noise. . .

Unfortunately, that modulation contains unknown information, and to filter it, you would have to know what its content is, and to know what its content is, you have to have a specific amount of power per bit to noise ratio to demodulate information at a particular speed. And if that could be done, BPL wouldn't have to operate at tens of dB higher than the present noise levels to be able to work at all.

And it gets even worse in that the narrowband systems we are using do not capture all of the transmitted BPL signal, which is spread out over spectrum and/or multiple carriers. So unless one wants to process tens of MHz of spectrum in real time, determine not only the nature of the signal, but its specific content, and do this for multiple signals present, in the presence of other signals... well, you probably get the idea.

And, if you did sample tens of MHz and manage all this, the present state of the art for DSP does not have the speed to do all this real time, especiall not for the claimed 200 Mb/s next generation DSP. Nor are there enough bits in the DSP to be able to duplicate the dynamic range of an analog receiver's ability to reject all of the out-of-channel energy in those tens of MHz.

Maybe someday, but even then, I am not sure, because someone will always want to add more noise in the hopes that the victim receiver will be somehow improved to be able to "filter" it out. And I can hardly imagine the complexities of this hypothetical system and what it will add to the cost and complexity of HF rigs. At FCC Part-15 noise levels across entire bands, all of the current spate of rigs would have to be scrapped in exchange for an unspecified system that has not been invented yet.

None of these techniques come without a price, as anyone who has listened to a DSP denoise algorithm can attest.

Ed Hare, W1RFI

 

5--></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (n1ir @ June 28 2004,165)</td></tr><tr><td id="QUOTE"></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (ke4pjw @ June 28 2004,15:41)</td></tr><tr><td id="QUOTE"></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (n1ir @ June 27 2004,06:27)</td></tr><tr><td id="QUOTE">1)Please look up 'deterministic'. It's either signal or noise, Ed. Which is it?[/QUOTE]<span id='postcolor'>
<a href="http://users.ece.gatech.edu/~mleach/ece6416/noisepot/chap01.pdf" target="_blank">
Noise is any unwanted signal that interferes with a desired signal. Most electrical noise can be categorized as being either random or deterministic. </a>[/QUOTE]<span id='postcolor'>
Would you be so kind as to point out this definition's citation? Please, a technical reference, preferably one with a physics base.

Many thanks,

73,
Chip N1IR[/QUOTE]<span id='postcolor'>
Chip:  What does a physics basis have to do with signals/system science, which is a branch of electrical engineering?

Are you going to derive system science from Maxwell's equations?

I suggest that, as I told my grad school roomy, who had a degree in physics, when he asked me about circuit design, that several courses were necessary to get a good feel for being able to realize a design from desired performance criteria.

You may have taught a course in signals, but without at least a BS in EE, you lacked a good deal of the underpinnings of realization of what you expect in performance from circuits and systems.  And, how to evaluate and adjust their parameters to achieve the desired outcome.

Its nice to have dreams, but, we need to have the tools to separate the plausible from the impractical.  And, as Ed has so aptly said, the cost of implementation, if some means were to be devised, would be such a burden that it would likely result in it not being accepted and deployed, except by those with very deep pockets, such as our government.

Best 73s,

Lee
W6EM

 

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (w6em @ June 29 2004,20:30)</td></tr><tr><td id="QUOTE">Chip:  What does a physics basis have to do with signals/system science....

Best 73s,

Lee
W6EM[/QUOTE]<span id='postcolor'>
That's it in a nutshell, don't you think? I find this very revealing, Lee.

Actually, I can see that I've had substantial impact and I find this gratifying. Everyone learns something. And the extent of that goes far beyond a simple thread.

A piece of educated advise: May I suggest that , in future dealings on this issue, that FACTS--be the guiding light? That, and the desire, practice, and implementation, of cooperation? Disputes on technologies don't settle well when emotion reigns. I have real fears that ham radio will suffer in such approaches.

These two issues--facts and cooperation-- will profoundly shape the practice of amateur radio in the next decade; a public service full of some good people and grand ideas, a hobby which I am innately proud to be part of and will continue to work on its behalf.

Great things lie ahead in the enabling of telecommunications and wireless. Are YOU ready for them? Are you ready to build bridges?

Signing off on a fascinating thread.

73,
Chip N1IR

 

Chip:  If facts, rather than supposition and misstatement had been the basis for development and the hastened rush to judgement on BPL, then we wouldn't be here now, would we?

There are other broadband options now, which do not produce interference HF interference.  Corridor Systems GHz approach, for example, for one, is an exciting approach for older and rural overhead lines.  Although, the cost of its installation and operation on overhead lines will need to be justified to be accepted by utilties, just like every other investment or expense not mandated by public utility commissions.  Of course, their approach won't work in underground utility areas.

Yes, I am excited about what the future holds for telecommunications, and especially the internet.  I'm still on archaic dial up access, and would welcome a WiFi wireless service if one were available in my area.  After all, I could then install a couple of guy wires to support the antenna and mast (cut to appropriate lengths, of course) for HF operation.  A reasonable approach to avoiding enforcement of CC&Rs, thanks to the FCC's OTARD provisions pre-empting CC&Rs for wireless internet service.

To date, the only facts produced are from the ARRL and NTIA studies.  And, the actual reports of interference by our brethren.  If proper, up front research and testing had been performed for BPL, it would never have been introduced.

78MHz worth of spectrum (if that much is truely necessary) is available now, in idle UHF television channels as well as microwave allocations.  The regulations are already in place to permit small, end-user two-way internet antennas, up to 3 feet, three inches in diameter or diagonal measure, free of CC&R restrictions.  So, what's left but development and installation of the equipment?

Yes, I'm excited.  Let's see affordable, dependable broadband wireless happen, but not with the potential risks to public safety and homeland security that come with BPL.

73,
Lee
W6EM

 

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (w6em @ June 30 2004,04:36)</td></tr><tr><td id="QUOTE">[/QUOTE]<span id='postcolor'>
Hi Lee,

I am sorry. It is a classic propaganda approach you are using. It certainly has not escaped others how you mixed fact with fear with mistake with personal attack with misqoute with out of context. A real pity for the point of view you wish to champion.

The fact that we are NOT discussing this via HF radio demonstrates, to some degree, ham's HF limitations in today's world.

HF radio is a legacy with some life left. There is a place for it, and even a need for it. How hams fare in that is likely to be shaped by events precipitated by a vocal 'ham' few, in the coming months. Some advice: make very, very sure that the very best foot is put forward. Others might not be as tolerant of these tactics.

May I sign off now, as was my request?

Best of luck,

Chip N1IR

 

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (n1ir @ June 30 2004,05:19)</td></tr><tr><td id="QUOTE"></span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (w6em @ June 30 2004,04:36)</td></tr><tr><td id="QUOTE">[/QUOTE]<span id='postcolor'>
Hi Lee,

I am sorry. It is a classic propaganda approach you are using. It certainly has not escaped others how you mixed fact with fear with mistake with personal attack with misqoute with out of context. A real pity for the point of view you wish to champion.

The fact that we are NOT discussing this via HF radio demonstrates, to some degree, ham's HF limitations in today's world.

HF radio is a legacy with some life left. There is a place for it, and even a need for it. How hams fare in that is likely to be shaped by events precipitated by a vocal 'ham' few, in the coming months. Some advice: make very, very sure that the very best foot is put forward. Others might not be as tolerant of these tactics.

May I sign off now, as was my request?

Best of luck,

Chip N1IR[/QUOTE]<span id='postcolor'>
Sure, you can leave any time you want.  I think you've been looking in the mirror, Chip, based on your vicious attempts to discourage those who oppose BPL for honest, factual reasons.

You came here to attack the efforts of others in response to facade and namecalling by UPLC and its sponsors.  Acting largely as if you were UPLC's personal representative.  You've done it to me,  Ed Hare, and others as well.

Take your own propagandistic, (and frustrated) basic physics mindset elsewhere.  And troll for troubles in some other forum.

If you had something positive to contribute, it wasn't in any of your posts.

If you have such a disdain for those who want to preserve and protect amateur radio, give up your license now and continue to root and toot for broadband or anything else to displace our spectrum as you have done on this thread.

I've said plenty on the record in the proceedings.  Why haven't you?  And, a good deal of it is my professional opinion based upon many years in the electric utility industry.  Years spent designing, maintaining and operating utility systems while you were probably teaching quantum mechanics and the like.  And, I'll back up what I've put on the record.

And, if "others" have differing opinions about what I've said, that's fine with me.  I'm open to any and all comments about anything I've said.

Yes, do find something meaningful and positive to occupy your time.  Perhaps there's another quark out there somewhere.

73,

Lee
W6EM

 

urging the Commission to ignore "armchair amateurs that still use vacuum tube transmitters" and listen to the reputable companies and entrepreneurs who are the real experts on BPL

Interesting. I'm apparently one of those armchair amateurs. Notably, the company I run has built a fixed-wireless and point-to-point microwave broadband service that reaches much of southwest Iowa. We take care of numerous community banks, school districts, medical facilities as well as your every day home and small business customer (oh, and amazingly it is 'symmetrical' service which the BPL lobby frequently claims is a unique aspect of their service). Not only do we work with amateurs (our towers are part of a linked repeater network that assist the National Weather Service office in reaching weather spotting hams across nine counties in our state), many of us are amateurs and have a great deal of respect for the FCC and radiofrequency responsibility.

At the same time, our regional power utility (MidAmerican Energy) cannot keep power running to our communities. Twice this spring, the community of Treynor Iowa has gone without power for many hours (the last time due to a single squirrel in a substation - redundancy? not&#33.

My home community of Tabor Iowa loses power when it rains, as it did two weekends ago (for half the day), has more than four miles of its transmission dependent upon lines along minimum maintenance roads (great planning by the power company as you can't access much of it when the roads are muddy), and the community jokes that you'd better keep a candle close if there's a raincloud in sight. MidAmerican, for all its billions (and expansion in the construction of new highly profitable generation facilities) simply cannot maintain its last mile. In October, we lost power for hours on a nice clear autumn evening (three minutes into Monday Night Football). Reason? MidAmerican re-routed service through a backup route to facilitate some installation of new poles, only to forget to calculate the load grain dryers place on the system October is harvest season, but then again, MidAmerican probably does not know nor care much about its non-generation customers. (I learned this the hard way when complaining about the power feed to one of our company towers which would blink in and out dozens of times a day - the power company engineer's answer? "Oh, you're out in the country - that's normal!") Western Iowans cannot trust their power to MidAmerican, and yet the BPL lobby seeks even greater priviledge and responsibility for these types of providers?

So who's "reputable" in this lot? The BPL lobby needs to be a bit more careful about the words they choose for fear of them coming home to roost. Technology, reliability and concern for the customer are often the last of their interests, while a quick buck from enhanced services or power generation and sales to California have greater appeal. Let's see you folks take care of what you've signed on for first before you get running off in yet another direction.

Jamie/W0JRS

 

Jamie:  An excellent post.  I sure wish that your wireless internet service was available here.  You would have my business!!

There's little excuse for the shoddy service that you've experienced from your utility.  Which appears to be a combination of poor design, and inadequate maintenance. The insulator flashovers from rain on the transmission line are probably the result of contamination not washed from the insulators, or insulators that have previously flashed over and have carbon deposits on them from tracking.  It sounds like either the offfending insulators should be identified and replaced with some more compatible with the environmental conditions in your area, or the entire line should be reinsulated with some of the newer silicone rubber/fiberglass insulators which perform much better in rural environments. Squirrels on substation transformers are a tough lot, but two, three-phase transformers or four single phase transformers in one substation should have been the design goal, to provide flexibility in such circumstances, in the event of a single transformer failure.  Especially when serving a community.  

There is absolutely NO excuse in today's environment, with computerized load flow and management software for overloading any lines or transformers and causing the aggravated, unplanned outage you described from a pre-planned construction clearance.  And, the same goes for the many momentary outages you've experienced.  Both are examples of very poor maintenance and operation by your utility.

You might want to summarize what you have described into a complaint and file it with your state public utility commission, if you haven't already.

73,
Lee
W6EM

 

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote (n1ir @ June 28 2004,23:47)</td></tr><tr><td id="QUOTE">Are you ready to build bridges?[/QUOTE]<span id='postcolor'>
Are you attempting to sell us a bridge?

Seriously, I am not willing to build a bridge that pollutes a natural resource, the HF spectrum. It simply makes no sense to throw out an over the horizon communications system that requires no infrastructure because the same frequencies can be used to deliver Internet Service to a few who who don't want to put up the money for a real circuit or put up with the latency of satelite broadband.

 

Ladies and Gentleman,
Rather than groan and gripe about Ms. Patterson's Press Release... Forward copies of it to EVERY amateur that you know - especially outside the USA.

After all, her comment is an insult to all amateurs.
Many of whom are engineers.

Underline (or bold) the knock against amateurs.
Emphasize the comment about saving lives...

Take the time to write a well-worded reply in legitimate protest and suggest that those you send it to do the same.

Her e-mail address is, after all, posted on her release.

Take a variation of your well-written letter and send it to Bush in the White House.

Let him know that we don't take kindly to this kind of treatment and that we're not neccessarily against new internet technology, just the interference that BPL potentially stands to cause.

If enough letters are written, they have to listen.
There are over 2 million amateurs ... if a good portion write to complain, we will be heard.

One letter at a time ... adds up.
If some well-versed engineers write in, maybe she'll rue the day that she wrote that press release.
I've already sent in my e-mails gentleman and printed up a letter for the White House.

It's time to make oursleves heard.
Sincerely,
Scott Verity KC2FBV