Slashdot Mirror
Sharing the Airwaves: Spread-Spectrum Broadcasting
NaDrew writes "From the SFGate: Hal Plotkin writes about how Spread-Spectrum broadcasting technology could revolutionize the way we listen to the radio, and make it incredibly easy for neo-broadcasters to start their own services. Sadly, he writes, the "often technically inept U.S. Congress has complicated the situation in recent years by shortsightedly instructing the FCC to sell or lease additional bands of spectrum that had been reserved for other uses." Not to mention "the media conglomerates that own most of the nation's TV and radio stations have a vested interest in the status quo and won't easily give up their hammerlock on what, in the end, are public airwaves." A fascinating article that also includes some history of Spread-Spectrum technology (did you know it was patented by Hedy Lamarr?)." A good primer to spread spectrum if you're new to the issue.
w00t!
I thought 1st april was gone already
Perhaps, perhaps, perhaps...
(did you know it was patented by Hedy Lamarr?)
That's Hedly!
*** Where are we going? And what's with this handbasket?
So why don't they just fix what we have!?
Wireless-Schmireless
Well, here goes, so waht? Another useless pice of shit inforamtion that no one really cares about. Blow me harder.
Did you watch the news recently ? See how a tiny country called Israel makes the US kneel down and make the largest country in the world look like a kid in front of a country not bigger than an american city ? How pathetic and laughable at the same time !
The congress tries to give private enterprice what they want. But it is conress fault! Can't they get the story right just once, for their tame little kittens.
Microsoft - Where would you like to go today, Maybe Jail?
Sure if you are not tuned in, it looks just like noise.
But if people are not careful what will happen is the noise floor is raised higher and higher till it drowns out signals.
Yah that isn't close to happening yet, but the way it's being hyped as if everyone and anyone can broadcast at the same time, it might happen sooner than expected.
Using spread spectrum technology greatly increases bandwidth available. We are figuring this out 75 years after the invention of radio, so wouldn't any one else out there be doing the same thing? Are we wasting time looking for a strong signal from space when a spread spectrum signal would look just like increased static coming from a planet.
Free cell phone tracking
finally...
Here is a mirror
I say we mod her down!
the interest level of this article is incredible! after being up for 20 minutes, there are a whopping 6 comments rated 1 or better, 12 overall.
*wave of hand from powerful alien* SETI is evil... you should ban SETI... You don't want to know about other worlds and aliens... Aliens don't exist, and they certainly wouldn't be visiting earth unnanounced to sample the local women... go about your business.
No! You don't say! What an obscure piece of historical trivia. Wherever did you discover that?
I suppose next you're going to bust out with the news that Milton Berle was hung like a horse.
Edith Keeler Must Die
RIAA: What, a new way to distribute music? Kill it quick, before we figure out that it could make us a boatload of money!!
US Military: That's our bandwidth! We need all the spectrum we can get to bomb an Afghan hut!
Steve Case: Did the military say bandwidth?? We should buy that up and meter it.
but I thought that part of the spectrum under consideration had also been set aside for wireless.
I know there was a small flap on something like this back last October, while everyone had their attention elsewhere.
Greed moves on
"It is a greater offense to steal men's labor, than their clothes"
That's what Pulsars are, basically a big galactic GPS / messaging system.
try { do() || do_not(); } catch (JediException err) { yoda(err); }
Important Stuff: Please try to keep posts on topic. Try to reply to other people comments instead of starting new threads. Read other people's messages before posting your own to avoid simply duplicating what has already been said. Use a clear subject that describes what your message is about. Offtopic, Inflammatory, Inappropriate, Illegal, or Offensive comments might be moderated. (You can read everything, even moderated posts, by adjusting your threshold on the User Preferences Page) Problems regarding accounts or comment posting should be sent to CowboyNeal.
The possibility of unfettered access to spread-spectrum technology for broadcasting must scares the bejeezus out of the RIAA. So far, their whole arguement against the web-based radio stations has been easy for them to try to enforce it because the pay-per-listen criteria is trackable.
However, if this technology becomes feasible to the average web-caster to broadcast their favorites tunes over the airwaves, then the measurement criteria for tracking who's listening goes out the window, and the RIAA has no power to enforce their rules.
Expect the RIAA to be on the side of the radio station conglomerates on this one.
Rule #1 -- Politics always trumps technology.
A journey into the statistical methods employed to create Comments That Agree . As I discussed in my previous journal entry, nearly 500 moderators were manually and permanently removed from the pool of potential moderators for giving positive moderation to one comment. While the manual banning of potential moderators by the Editorial staff is not documented, the source code used to accomplish this is readily available and the practice appears to be quite commonplace. The reasonable questions that arise from this practice are: how many moderators are being banned, what is the objective, and what are the actual results? The Slashdot Editorial staff has repeatedly stated that they don't have time to answer these questions (they're certainly not addressed in the FAQ), so it's up to us, the readers, to ponder them. How many moderators are being permanently banned from the moderation pool? No one knows for certain except perhaps the Editors. Let's look at what we do know. Five hundred moderators were banned for moderating one comment. If we assume that one such comment is posted on a daily basis, that is approximately 185,000 potential moderators banned per year. That post was probably an exception, so we must revise our number. Jamie McCarthy made a post to a User-Created discussion which is deleted every two weeks, so I must reproduce his comment by cut & paste: "Well, again, we have the logs, so we know what we're talking about. We log both how many times we give mod points, and how many times we would have given mod points but didn't. In the former category: 99.73%; in the latter, 0.27%." - Jamie McCarthy, Slashdot Editor Additionally, Rob Malda made a related comment in a User-Created discussion: There are a quarter of a million daily readers, but (and I just checked) only 1.2% of them post. So understand that those of you posting in the forums are already a minority of the community. - Rob Malda, Slashdot Founder & Editor Now we have some numbers to run with. Of the 250,000 people who read Slashdot, 3,000 of them have an "Interest Level" high enough to post comments here. This "Interest Level" stands at 1.2%, or .012. Now that we have the "Interest Level" for comments, we can use it to determine the "Interest Level" for Moderating & Metamoderating. Moderation requires less personal risk, so let's assume (to be as conservative as possible) that far more people want to moderate comments than post them. Let's assume that up to five times as many people want to moderate comments. There are probably far fewer, but since we are dealing with an assumption, we should make it a conservative one. This makes the "Interest Level" for Moderation about 6%, or .06. Now, Jamie has stated that 99.73% of readers receive moderator points and are not banned. Their "Interest Level" is .06, which means that (99.73 *.06 = 5.98) 5.98% of these people (at most) actually use their points. Now we have the banned moderators, the .27% that Jamie mentioned, who have been banned for bad moderation. Banned moderators have an interest level of 100%, because they have all used their points to get banned by an Editor. So, now we have a figure for the number of Moderators and Metamoderators who are included and excluded by the manual intervention of the Editors. (.27/(.27+5.98)) = .045, or 4.5%, is the lower bound for the percentage of moderators being manually excluded from the pool. If you run the numbers again assuming that the Interest Level for Moderation is the same as the Interest Level for posting comments, you arrive at a figure of 18.4% of moderators being manually banned. This would be our conservative upper bound. So, depending on how interested people are in moderation, between 5 and 18 percent of moderators have been manually banned from participating by the Editors.
What is the objective of the Editorial staff in manually removing User Moderators? That's a really tricky question to answer. Keep in mind that the Editors have gone to extensive lengths not to answer that question, so we must assume that it is an emotionally loaded subject. However, we can interpret some of their actions to arrive at an answer. The post mentioned in the beginning of this article was repeatedly moderated as Offtopic by many Editors. Rob Malda described it this way:
however only a smaller percentage of those moderators actually use their points... hundreds of users moderated it up [and I subsequently banned them all] I modded it [the comment] down a few times too. - Rob Malda, Slashdot Founder & Editor
Note that text in brackets was added by myself to reflect what we've learned. Reading that statement makes it pretty obvious that the purpose of removing Moderators from the pool is to ensure that the results of the Moderation system are consistent with what Rob Malda believes that the results of the moderation system should be. Moderators are chosen from a pool of Slashdot users who have not moderated contrary to the wishes of the Editors in the past. As the Slashdot FAQ states, "The Slashdot Editors have unlimited mod points ... These moderations represent approximately 8% of all moderation". In short, nearly ten percent of Moderation is accomplished manually by the Editorial staff, and the rest of User Moderation is accomplished by users that have not disagreed with the Editors about how to Moderate. What does this mean?
When surveying the impact of the Moderation system, there is one overridingly important statistic. That statistic is that over 99% of Slashdot readers do not post comments. Keep in mind that the default view of Slashdot has a threshold of one. This means that if you're moderated to zero or less, 99% of the people who would have read your comment... won't. Books could be written about whether or not blocking communication to 99% of the possible audience constitutes "Censorship", whatever that means today, but for the purposes of this essay, the point is moot. Suffice it to say that Moderation determines 99% of visibility, statistically. Now, consider that the Slashdot system, as a whole, is a constantly evolving system in which Moderators can transition from unbanned to banned, but not vice versa. Moderators who moderate differently than the "guide" Moderations of the Editors (which constitute 10% of the Moderation) are removed from the pool of influence. Therefore, Slashdot as a system moves in only one direction: towards promoting comments that are Moderated in agreement with the Editors. What is the role of Metamoderation? Let's look at the FAQ:
according to Meta Moderation, the fairness of these [editor Moderations] is statistically indistinguishable from the moderation of non admin users (92-93% of moderations are ruled 'Fair').
Keep in mind that the 5 to 18 percent of Slashdot Moderators who are banned from participating in Moderation are also banned from participating in MetaModeration. The purpose of MetaModeration, therefore, is that of reinforcing agreement. Those who have agreed with the Editors in the past are allowed to vote on whether the Editors moderate fairly. Not surprisingly, this subset of potential MetaModerators often agrees with the Editors. If they didn't, they'd probably have been removed already! MetaModeration, therefore, serves to reinforce agreement with the Editors among the selected Moderator pool, and Moderation serves to enact agreement with the Editors among the comments visible to 99% of Slashdot's readership. We only need one more quote from the FAQ to understand what this means:
Goals [of Moderation]: 1.Promote quality, discourage crap.
Since the Moderation system is a self-reinforcing system that promotes comments that agree with the Editors, we must assume that this comment means two things:
What the editors believe is quality.
What people who disagree with the Editors believe is crap.
That may be a strongly worded value judgement, but it stands as a conclusion easily & objectively reached. But aside from this value judgement, Slashdot stands as an example of a best-of-breed solution for those who wish to create a community that promotes agreement. Slash appears to have been specifically designed for this purpose, and it can be employed to create a community that agrees about.. just about anything! For instance, ask a Slashdot reader if Linux is a great Operating System. The answer will almost certainly be an emphatic yes! Rob Malda has created an excellent system for managing a userbase into agreement, and for the most part, the users agree with the system. Which was probably the whole point.
Slashdot: News for Nerds, Stuff that Matters. Comments that Agree.
So we're moving. This is a big one. Besides leaving Holland for the land of Ann Arbor, this move is significant because Kathleen and I are doing it together. It hasn't been easy, but we're on the home stretch now.
;)
This morning however I awoke with a headache, but the aspirin is packed. No matter because all the glasses were packed too, so I have no idea how I would swallow the pills. And breakfast coffee? Showing the foresight for which I am famous, we made sure that the coffee machine was not packed. However I forgot to make sure I had access to a coffee cup.
Meanwhile the cats frantically sprint from room to room. They know something is going on. They are tipped off by the countless brown cubes that have replaced all the objects that they previously could (A) Knock Over (B) Sharpen their Claws on or (C) Rub their faces against in some bizarre ritual that I will never, even if I own a million cats, I understand. What fun is being petted by the corner of an endtable?
The only thing still plugged in is my router, my cable modem, my laptop, and my Tivo. The Tivo snagged this weeks South Park, and last nights Daily Show. It may be saturday before I actually have a chance to watch them, but dammit, I shall!
But first, the ritual loading of trucks, where the friendly men put everything you own into an impossibly small space for shipping it hundreds (well, 155 anyway) miles. And then, the waiting, since the ritual unloading of the impossibly small space doesn't occur until tomorrow leaving me in a state of limbo sort of like Zod and Co in Superman II.
It could be worse. But only if all the grocery stores in Ann Arbor are sold out of Aspirin & Coffee Cups.
Oh, and don't email for a few days. I'm busy
Visitors to the website slashdot.org will by now have surely heard of the act of Moderation. This is where a contributor's post can be 'Moderated' either positively or negatively, depending on how the Moderator perceives the value of the post. There is a sliding scale of total moderation points, from -1 to 5, along with snappy summaries of the reason for moderation, such as "Funny", "Insightful", or the ever popular "Troll". An additional benefit offered to Moderators is the ability to ban a poster from contributing, by negatively moderating enough of his postings in a 24 hour period.
In order to retain some level of fairness for the Slashdot population, the Slashdot Editors (adopting the role of 'Benevolent Dictators') have implemented a scheme whereby regular users of Slashdot, chosen essentially at random, are given the ability to act as Moderators.
This underlines an inherent flaw in the system. Psychological studies have shown that in any community, no matter how small, should a random sampling of people be given the slightest grasp of power, they will immediately abuse it. There is a primal, evolutionary desire in Man to place himself higher than his peers by whatever measurement they can muster. Slashdot Moderation provides the ideal means for which a man can prove himself more equal than others.
At the risk of invoking Godwin's Law at such an early point in my thesis, I have no choice but to compare Slashdot Moderation to the systematic genocide of the Jewish community in 1930's Germany.
A bold statement, I admit, and deliberately designed to shock, but I feel the statement is necessary. I shall now offer a more rational explanation, as well as a comparison of the parallels between Slashdot Culture, and the National Socialist regime.
First, some history. National Socialism did not spring up overnight. It grew from a feeling of national bitterness and resentment at the war reparations Germany was forced to make after World War One. Germany was a broken country, populated by desperate starving people. And to the desperate, an extreme ideology begins to seem like a rational choice.
The advent of new technology forces a paradigm shift in the way the beholders of that technology think. The Christianity Meme was made wide spread by the invention of the Gutenberg press. And the rise of National Socialism was made popular because of the invention of Cinema. Here we had a new means to control the flow of information to the populace, that they are willing to unquestioningly listen to due to the 'novelty factor' of moving pictures. It is no coincidence that some of the best Cinematography of the early 20th Century came out of the National Socialist propaganda machine.
Why is this the case? It is yet another fault of man that a new means of distributing memes is perceived, due to the 'newness' of the medium, to have a greater 'validity' than older media. Those harnessing new inventions have the power to win control of the hearts and minds of others.
With the tools in place, who should the National Socialists target? Clearly, as a counterpoint to Man's desire to hold power over others, there is also a desire to resent the success of others. If someone is successful, they reduce the self-worth of their beholders. Although times were harsh in Germany in the prelude to World War II, there were still successful inhabitants of that country. Possessing shrewd business acumen as well as the contacts in other countries needed to maintain support in such a poverty stricken and broken land, who else should deserve the wrath of the populace more than the Jews?
Fast-forward to the latter quarter of the 20th Century. Computing technology is focused in niche markets, and limited to big successful companies like IBM and Microsoft. As the markets were limited, there were also limited opportunities for employment. This gave rise to a rising number of college dropouts, seething with resentment and unable to relate to society beyond the staccato clatter of keyboards and the pallid green glow of an 80x24 text display, and lacking the basic business skills (and a smart suit) needed to secure employment at one of these companies.
At this time, a new invention was beginning to take hold in College campuses throughout the world. The Internet. As with the Gutenberg press and Cinema beforehand, this new technology would grow to spread one of the most virulent memes of the modern age - Open Source Software, created as the antithesis of successful business practise.
So, the parallels between the birth of Anti-Semetic National Socialism and the birth of Open Source Software have been made. Of course, it is easy to claim that A=B without providing further logical evidence in support. So, the next task of my thesis is to provide further parallels, and bring this discourse back to the initial focus on Slashdot Moderation.
Slashdot was conceived, in it's original 'Chips 'n' Dips' incarnation, as a vehemently anti-corporate Open Source website. Roughly 10-15 years down the line from the birth of Open Source, it has become saturated with propaganda, and now forms the centrepiece of the Open Source Development Network. An authority in it's field, Slashdot's success is in no small part due to the ability of the editors to 'pick and choose' valid news articles submitted by users, and present the same old tired "Open Source Good / Closed Source Bad" rhetoric time and time again, dabbling with anti-copyright and the right of the 'common man' to remove an artist's ability to gain compensation for the work. In essence, this is similar to the 'paring down' of artistic worth in 1930's Germany. If no-one is willing to contribute valid and vibrant art to the community, then all art shall become harsh and functional, possessing a certain intimidating aesthetic.
Which leads onto Open Source's shining achievement - Linux. This diatribe is not aimed towards Linux in particular, as it is a well-oiled, well-tuned machine. A technically adept Operating System, it is worthy of admiration by any rational man. The point of this thesis is not to attack the art produced by Open Source coders, which in itself is worthy, but to enlighten all as to the political processes behind the OSS movement.
By the same scale, it is hard to fault Mercedes for the technical excellence of the vehicles which were used by the National Socialist party. But the politics behind the party are what taint the image of Mercedes' vehicles of the era. The Swastika itself is a benign symbol, found this day in such diverse locations as Pokemon cards, but is permanently tainted with the history of the acts made under its auspice. In the same way, companies switching to Open Source solutions will begin to regard the Penguin with the same trepidation as their profits fall.
It should be worth noting at this point that IBM, previously one of the world's greatest companies, has begun reporting servere financial losses, no doubt due to its adoption of Open Source practises. This epoch-making event was NOT reported on Slashdot, even though articles were submitted.
And what of the other great company mentioned above? Microsoft, aka Micro$oft, Mickeysoft, Microshaft, Kro$oft, and many other derogatory and undeserved names. Throughout the previous 25 years, Microsoft has grown from strength to strength, again possessing shrewd business acumen as well as providing products that people want. This makes them the number one target for the OSS movement. Incapable of standing by their own merits, the OSS zealot would rather attack Microsoft as a priority than produce anything of worth for their community.
Slashdot Moderators, crazed with their limited new-found power, exhibit this behavior. It is a sad state of affairs that the majority of article moderations are negative. Where is the positive feedback and sense of social contribution? Nowhere to be found. Moderators are too focused on putting their peers down to make themselves appear superior, rather than doing the hard work and becoming better on their own terms.
As the National Socialists required a scapegoat, Slashdot Moderators require a constant stream of Postings to label '-1, Inferior'. Once a posting is reduced to the score of -1, it becomes invisible to the casual user. Again, this is a parallel to the Ghettoization of Germany upon the election of Hitler.
In essence this would not be so bad, were postings to be evaluated on their own terms. However, alongside the moderation of their postings, each user has a 'Karma' value, namely the sum of their worth to the Slashdot community. As a user's posts are moderated up or down, so their Karma fluctuates. As Karma becomes negative, a user's default posting score is reduced, until they are posting at a default of -1. Again, ghettoizing PEOPLE, not just their opinions.
This ghettoization is reinforced with the often fake belief that a negatively moderated post, and therefore the poster, is a "Troll". (Is it any wonder that such a name has been chosen to describe these people, invoking mental imagery of facial disfigurement and hooked noses?) As the Jews were accused of fraud, dishonesty and being subhuman animals, so too are Trolls accused of FUD, Crapflooding, and obfuscated goatse.cx links. Quite often, these 'undesirables' are capable of providing a valid insightful comment on a topic, but because it is in opposition to the Political dogma of Slashdot they are moderated back into their ghetto. The person becomes moderated, not their opinion.
This is just the thin end of the wedge. Although, as memes are transient, it is difficult to silence an opinion, it is trivial to silence a person. Upon the rise of National Socialism in Germany, the populace were motivated by propaganda into entering the Jewish Ghettos en masse with the sole purpose of causing as much damage as possible to Jewish businesses and residences. This parallels far too accurately with the Slashdot Editor's non-discouragement of the act of IP-banning. As mentioned above, this occurs when an individual user's postings are repeatedly moderated down in a short period. They then become incapable of posting any contributions themselves. In essence, they have been silenced, regardless of the worth of their postings.
Of course, the editors claim that Meta-Moderation is the panacea to solve this clear abuse of moderating privledge. But if a Meta Moderator is presented with a list of moderations that they disagree with, such as this targetted 'silencing' mentioned above, they cannot note them as such without in turn becoming an 'Undesirable' themselves, as too many Disagreements with the Moderation groupthink also result in loss of Karma.
Throughout all of this, the Editors have claimed a false level of detachment from the acts of moderation. In a same way, as the National Socialists gathered their power and began working on their Elite Political wing, The SS, they too remained detached from the civilians working in their name. Why? Because after inspiring the populace to such acts of violence through their propaganda, they could then claim that they were only giving the people what they want.
And then began the next stage of the atrocities. The Gestapo, Germany's secret police, were recruited from the best and the brightest of Germany's elite. As is the case now, the best and the brightest of society were often shunned and ostracized in society. In essence, the Gestapo were a tightly controlled 'Geek Army' of intelligent young men with a burning, seething resentment of normal society. The perfect psychological profile for the cause.
After all, give a normal man (with an active sex life) a gun and he will use it responsibly in self defence. Give a geek a gun and he will behave according to his sociopathic logic and hatred of the world he arrogantly presumes to be distant from. Ask yourself why Slashdot flat-out justified the murder of innocents at Columbine. And then ask yourself why, even for a brief moment, you almost began to sympathize with the killers after Jon Katz' manipulative and pseudo-emotive Hellmouth articles.
How this relates to Slashdot is clear. The majority of Slashdot posters are Sociopathic OSS zealots, unable through lack of social finesse or personal hygiene to mate regularly. Sexually and emotionally frustrated and with grudges to bear, incapable in their blinkered sense of self-righteousness of accepting any dissenting opinion than the OSS cause. Now give these people the opportunity to Moderate these dissenting opinions. Of course they are going to want to silence them, by any means necessary.
Now, the Slashdot Editors have admitted taking this silence of opinion into the next stage, by moderating whole swathes of 'undesirable' posts negatively. And then permanently banning anyone who moderates said posts back up from moderating EVER again! The result of this new policy? The few Moderators with any sense of fairness and decency are removed from the moderation pool, leaving the power ENTIRELY in the hands of the zealots. Clearly, positive moderation is discouraged under this regime, which is a direct parallel with the way the National Socialists moved their own sympathisers into positions of power throughout Europe.
So how does this compare to the genocide performed in Auschwitz and their ilk? I would like at this point to explain that in NO way do I wish to belittle the horrors that were performed in the name of National Socialism. The six million innocents killed were a cry of anguish from which humanity may never recover. And a vast distance in time and scope from a few banned posters on some shitty "My Favourite Links - now with comments" website. But these stories need to be retold before the horror is lost forever.
For the only thing that we learn from history is that we never learn anything from history. Time and time again, the St. Vitus dance is played out, we make the same mistakes, and we perpetually fail to see the warning signs.
So, moderators, the next time you moderate a rational, insightful post down, maybe because you disagree with it or because it's posted by a 'Known Troll', just ask yourself this...
"Am I really contributing to the Slashdot Community, or selfishly destroying it?"
If spread-spectrum is allowed to flourish, everyone will have their own home-station, just like the web allowed them to have their own homepage...
Get ready for broadcasts of little Jimmy's first burp, and little Sara's first oboe recital.
For a preview of things to come, review the recent history of mp3.com--high quantity, low quality (followed by corporate buyout?).
I went to the city because I wished to live without deliberation.
Linux, BSD, FreeBSD, Open BSD, Net BSD, M$, illuminati, Ruby Ridge, Conspiracy,BeoWolf MacOS first post, flamming hot tarbaby grits, MPAA, RIAA, DeCSS,.
end troll mode begin while offtopic {
I like final fantasy 9, the princess boots me into multiuser mode and that's a good thing. The bluemage drives me bats and that's a bad thing I also have no clue what i'm doing in the game and that's good and bad good so that I don't chease untill I get a walk through bad because I might mis something nifty and that's bad.
-4 off topic
-1 troll
The european Digital TV and Radion systems already
use spread spectrum technology (though not
frequency hopping AFAIK) and have been since
they came online years ago. Time for the US to
play catch up (again).
you're probably kidding, but man taht's interesting!
The problem is that Spread Spectrum makes *LESS* effecient use of the spectrum vs frequency division multiplexing. Yes, I am an electrical engineer, and we studied this in class.
The US government sells its services to the highest bidder, while it builds new infrastructure using the lowest bidder. This guarantees low quality in all government services and projects. With regard to the FCC, clearly it is in the hands of the (increasingly few) media corporations.
If those guys at Waco had been broadcasting nationally from within their "compound," do you suppose it might have turned out differently?
You're assuming aliens would be using radio at all and haven't discovered a far better means of
communication. After all, across space almost any form of EM radiation travels as well as radio
waves , they could just as easily be using light.
SS transmissions still use discrete frequencies at any one point in time as they hop around the spectrum. Since SETI monitors wide portions of the spectrum simultaneously, you would actually be able to observe the hopping in real time as the different frequency bands become active with non-random signals. No matter what method of SS transmission you use, as soon as you send non-random data, this will be detectable at any frequency point of the used spectrum. Unless of course your objective is to not be observed and you hide your data in white noise (using steganographic techniques).
So beautiful. So brainy. Sigh ...
Um. Radio is light is electromagnetic radiation. But radio has a benefit, because it is not absorbed by air. Why? Because it's long-wavelength. Basically any gaseous atmosphere is going to be transparent to radio waves, so they are probably using that - probably a liquid environment will also be transparent to it.
You're also wrong that any form of EM radiation travels well in space - dust really sucks, and it preferentially absorbs higher wavelengths (because the dust can absorb them). Radio travels well in space, light does not.
Besides, SETI is looking at an 'intelligent' portion of the spectrum (I believe... they may have switched) - the 21 cm line of hydrogen. We can't look at any large portion of the spectrum - that's really friggin' difficult. So we assume that if they're trying to contact us, they're using an intelligent wavelength.
SETI isn't looking for stray communications, in any case. They're looking for a signal intended for us to notice. If SETI fails, that doesn't mean that there isn't anything out there - it simply means they aren't trying to contact us in the way we think they are, OR they aren't trying to contact us at all.
Great! Now we get every little shit on the planet running his own barage jammer screaming "It's my right!" Some of us actually NEED that low noise floor. It will be very bad when navigation signals go away because people are snarfing any bandwidth they feel like stealing. Existing ultrawideband devices already approved by the FCC measurably raise the noise floor and significantly reduce the SNR of ATC and GPS systems.
I sincerely doubt that an ET would transmit anything we could understand unless they are specifically trying to communicate with young civilizations.
Firstly, compression, by its nature, removes redundancy and order from a signal. Since we would expect an advanced civilization to use near perfect compression to communicate, their signal would look like noise.
Secondly, how long have we had technology that could communicate between the stars? 100 years, tops. We're already discovering that the way we've been doing it is not the best way. 100 years is a blink of an eye in the age of the universe. Very, very few civilizations would be this early in their development right now. So very nearly all civilizations are probably using something that we've never even had the vaguest notion of to communicate. We're still cave men looking for fire signals while everyone else is using compressed spread spectrum radio for communication.
Light is EM radiation too? Gee , thats for letting
me know, I'd never have guessed.
And interstellar dust will absorb wavelengths that
are similar to the grain size which is why some
clouds absord infrared more than visible light
and x-rays go straight through. It depends where
you are. Yes radio travels better in gases but
if these aliens communicate between planets they
could be using anything as I said since interstellar
absorbtion is not relevant on the solar system
(or indeed even local star group) scales.
I have been at the forefront of communications R&D
for 30 years. I can absolutely tell you this is
a load of crap.
Because of the near/far problem, spread spectrum
can't be suitable for broadcasting.
"Radio travels well in space, light does not."
Guess that's why I can't see the stars at night.... oh wait...
*I love sarcasm*
Pardon my FCC frequency allocation ignorance, but how much does Earth radiate at 21cm? (roughly 1.4GHz) There appears to be this presumption in SETI that they're trying to contact us. But other than a couple of bursts, are we trying to contact them? Or have we set the band aside as a quite space for radio astronomy, so on a random sampling nobody would find us?
The living have better things to do than to continue hating the dead.
The FCC isn't interested in increasing the number of radio stations out there. The RIAA doesn't want more broadcasters competing with them. What the government and big business want is as few channels and companies as possible so that they can have tighter and tighter control. For example, if you set up a pirate radio station (ie. you don't pay the FCC's fees), then the FCC will come and shut you down ASAP. This isn't because they're "protecting the airwaves", it's because you aren't paying them. It's been affordable to set up your own FM station for a long time, but the FCC's licenses are extremely high in order to keep normal people off the air.
I'm not sure about the actual numbers, but I think it's in the hundreds of thousands of dollars a year to keep an FM music station on the air.
Travis
"Light" usually implies "electromagnetic radiation". If you meant visible light, you should've said visible light. I was just saying that your terminology was a little ambiguous.
Interstellar absorption is VERY important on local star group scales! Anything smaller than about 1 micron is basically unusable on space scales: it's a power concern. For anything less than 1 micron, you have to transmit MORE power to get the same signal to the receiver. In that case, you'd be an idiot to use that frequency and not the clearer, low power one.
There's a reason we use radio to communicate with satellites and space probes - because it's intelligent, and far easier than visible light (aka lasers). While they MIGHT use lasers, they'd probably only do it for point-to-point connections (planets) and not for spacecraft.
Radio will never go away, not until we find a new medium to broadcast through. And in other civilizations, it won't go away either. It's fundamentally a good region of the frequency spectrum to use.
If you could see radio, you'd see a HELL of a lot more than just stars.
The wording (and context) obviously meant "radio travels better in space than light does" which is true.
It's easy to deal with absorption when you've got a transmitter as powerful as the Sun.
spread spectrum is noisy, tears up vital communications necessary for storm chasing, wipes out or interferes with repeater operations, and is a general nuisance to the Amatuer radio community. We provide many disaster relief services, not to mention the tornado and heavy storm tracking to help the weathermen confirm or deny potential problems shown on doppler and other radar systems. The ARRL and several other ham friendly organizations have been fighting the spread spectrum lobbyers as well as the little leo (low earth orbit) sattelites that infringe on our allocated spectrum. and..... lets not even get started on lowjack.......... Seriously, this is a budding problem that needs to be fixed!!!
I think the #1 thing the Electrical Engineers out there are missing is the impact of data compression algorithms. I'll grant them for now that its less efficient (how about some numbers as to how inefficient it is), but with proper compression/decompression algorithms, the same signals today should be ten times smaller, or, the same frequency can broadcast 10 stations more than it used to. That opens up a lot of space if the "property rights" aspects of transmission were shattered. If a concept like spread is used which fundamentally is less efficient but destroys the monopolies is implemented, I think data compression can bypass any inefficiencies.
Hey, I'm just your average shit and piss factory.
Several years ago a considerable amount of spectrum was sold by North American and European governements for huge prices in the tens of billions of dollars. However, little money exchanged hands. The bidding "down payment" was small, so many sham companies speculated. These huge amounts are just coming off the books. Some of the companies went into backrupcy with these huge debts. The governments also have to write off huge revenues that never materialized.
Therin lies the real problem with spread spectrum vs. conventional broadcasting channels. The limitations of conventional communications techniques is part of what stimulated the development of these more efficient algorithms. And since different groups are confined to their own frequencies, there was little stepping on toes.
But with spread spectrum, there is no pressure to be efficient, because there are no direct limitations on how much you can broadcast. The only problem is background "noise" from other broadcasters, and the easiest way to overcome that is with a more powerful broadcast. The obvious result is an escalation of more people talking louder.
It's like being in a nightclub, where everybody has to scream and repeat themselves to make themselves heard, but communication is near impossible anyway. The only one that can really be heard are the super-amplified guys on stage.
What we need is a more efficient and publicly-accessible use of the airwaves. Deregulating them will give the folks with the big antennas more control, not less.
---If you can't trust a nerd, who can you trust?
As usual, everybody tends to oversimplify spread spectrum and it "magically" works. Nope. Not at all. I wish it were so simple, just like CDMA was supposed to be. Well, because the signal is supposed to look like noise, at least in a CDMA cell phone, you have to effectively manage all the power levels of the users on the system so they don't step on each other. Thats why you have specs like ACPR (Adjacent Channel Power Ratio). Well, power control is a bitch. And you wonder why CDMA cell phones are much larger than their GSM counterparts.
In theory, the real sell on CDMA is spectrum reuse (and security), but thats theory. Its still better than GSM, but like a friend of mine told me once: people only develop complexity to hide mediocrity. And the academics might love the spread spectrum stuff, but its academics... not the people working in the field who have to deal with all the nasty issues academics don't deal with.
I'm not a know-all of spread spectrum issues, and it definitely has some great uses. But I don't think it would be very useful for 1 way communications like radio(unless it needs to be secure - like say...a cruise missile). It really peeves me off when somebody writes about something they no idea about.
Is there anyone who is doing a Spread Spectrum audio or video project?
It would be kind cool if an open Spread Spectrum video standard came out.
Use a 802.11 switch with a 1 watt amp to cover your neighborhood with reruns of Wargames or Commander Taco Eats Michigan.
You say things that offend me and I can deal with it. Can you?
Why wouldn't UWB be used for everything that must be transmitted if it's so great?
Given that:
Their choice is to view it and bomb it from far away by remote control or view it and bomb it close-up-and-personal.
It's still full of terrorists armed with hi-tek antiaircraft missiles when they need to bomb it.
Doing it by remote control needs a lot more bandwidth.
I'd say they have a good case that they DO need all the bandwidth they can get.
Or at least all the bandwidth they currently have MIL-spec remote-sensing and remote-bombing equipment set up to use, so they don't have to go have more designed and built while the terrorists are moving to a new hut and blowing up more skyscrapers.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
This reminds me of the old joke of a drunk looking for his keys under a streetlight. Asked if he lost his keys there, he says "no, but the light's better here."
the "[multiple derisive characterizations deleted] U.S. Congress has ... shortsightedly instructing the FCC to sell ... spectrum that had been reserved for other uses."
"... what, in the end, are public airwaves."
Like the land is all public land, and we're all tennants in government housing projects?
One of the problems with the radio spectrum is that there's a limited amount of it. With the "public airwaves" and "licencing this public trust" model the government's central planners have kept large blocks of spectrum unutilized or underutilized by older technoligies that make less efficient use of it.
One of the most effective methods known to handle the allocation of a scarce resource is a market, where people can OWN pieces of it, subdividiing and trading them as convenient and profitable - which, in the absense of government interference, often ends up with the pieces being used for the most-valuable-to-people purposes.
Like land, there's only so much spectrum. Like land, some uses can "leak out" and pollute neighboring pieces.
The government has decided to try an experiment and switch from the central-planning model to the property/market model for part of the spectrum, to see if that works better.
Of course this gores the oxen of the people who are currently using the spectrum they're selling, so they complain (and often rightly so).
And of course it also gores the oxen of people who have a political leaning toward central-planning, prompting them to spew rhetoric. This set of people apparently includes Hal Plotkin of SFGate.
It's a pity, because the rhetoric obscures anything of interest he might have had to say.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
Using spread spectrum technology greatly increases bandwidth available
This just isn't true, any more than weaving around increases the width of a roadway. Sure, it might let you dodge some obstructions, but in the process you become an obstruction to other trafic. The total amount of information that can be carried doesn't increase. Just like in the weaving-around-on-the-road analogy, you have to ask, what would happen if everyone did this? The answer, of course, is that to a good first aproximation all those other SS broadcasters would look like noise to you; so the ambient noise level goes up and the S/N ratio falls, meaning less information gets through.
How much less? well, in an ideal world, if you do everything right you only lose exactly as much as you thought you'd gained. TNSTAAFL.
Each photon you reveive can only tell you so much. You can't beat the uncertanty principle with hand waving.
-- MarkusQ
Spread Spectrum is no magic bullet.
,or.. that other way (how does one describe DSSS?).
Instead of taking a section of spectrum, and, say, dividing it into a hundred equal slices frequency-wise and assigning a slice to each of a hundred users, you take that same spectrum and allow thos ehundred people and divide the spectrum up time-wise,
The point is.. it's not a magic bullet. There is still limited spectrum, and hence, limited bandwidth.
Whether it's common spread spectrum (DSSS, FHSS) or the new UWB thing everyone talks about every six months... it's still limited.
The benefit of spread spectrum over other methods is simply that radios can all be equal, and the 'sharing' can be accomplished algorithmically, rather than by physical frequency boundaries... which should make things more flexbile.
In my humble opinion, frequency hopping and spread
;)
spectrum are not the same.
...says an M.S. in electrical engineering.
I thought it was common knowledge
I think there is too much power and money concentrated over the holding a broadcast spectrum. We have to run ahead of competition and install as many of IPv6 routers as possible, hopefully converting internet, to have multicast.
Multicast will allow *anyone* to have a radiostation, and few even a video station, at flat cost.
Running smashing your head against the wall is not the best way to use yourhead, perhaps, run around the wall, remove supporting beams and it will fall by itself. I think cause of bandwidth to be shared by companies is a lost cause...
The amateur service is intended to be more than merely a backup yacking system to cellphones. It's supposed to encourage experimentation with new systems. Sadly, the current FCC rules don't allow for much useful spread spectrum experimentation by hams, but the truth of the matter is that existing commercial systems could be ported to the amateur frequencies, and do the jobs you mention (emergency communications) far, far better than the 1950s FM technology you're clinging to.
Look at what happened to Packet Radio in the Amateur Service; we built it, they came, but then the FCC issued and enforced inane and archaic content restrictions on the use of packet, and the experimentation died out. The FCC is doing it to us again, all in the name of control.
...-.-
Heheh... thanks for the laugh.
And here I thought the Super Huge Interferometric Telescope poster we posted at that same meeting was the wackiest thing there... :)
[TMB]
2) Inter-Modulation Distortion. This is a general class of problems resulting from non-linearity in amplifiers. It manfests itself on a spread spectrum link as noise --just like the near/far problem. Your options for getting around this problem in a spread spectrum receiver are few: Basically all you can do is build a higher power front end amplifier (consume more power). With narrowband systems you can take advantage of resonant circuits as well.
3) Sequency management. Someone has to coordinate these things somehow. Many are embracing spread spectrum as a way to get rid of the FCC. That's unfortunate. Yes, they're doing their job quite poorly and yes, it's been this way for a long time. That doesn't mean anarchy is better, or that the FCC's mission is irrelevant.
4) Data transmission != spread spectrum. Efficient use of spectrum is laudable. That doesn't mean that you must spread to be efficient, however. There are plenty of very well known modulation techniques which can be used for data transmission. The discussion of data broadcast or point to point data transmission has no bearing on whether one ought to use spread spectrum or not.
5) Making a transition from narrowband communications to spread spectrum communications systems is too expensive, difficult, and impractical to consider. You simply can't change every aircraft radio and air traffic control facility overnight. You can't just shut off all broadcast stations and tell everybody to buy new radios. You'd have a major riot on your hands.
6) Current Broadcast programming sucks. Did adding all those channels to Cable TV improve regular TV programming? Does anyone think XM radio will do good things for FM radio? Get real.
Most of the discussion on spread spectrum right now is more about the disadvatages of narrowband when scaled up and the advantages of spread spectrum on a small scale. However spread spectrum doesn't scale up any better than narrowband communications has. The technologies and limits are still the same. This is not a magic solution. This is merely one method out of several for signal multiplexing.
I can imagine a day when spread spectrum systems will be more common. However it does very little to solve issues such as re-engineering the FCC to be less flaccid and useless, sending high speed data over the airwaves, or how to improve broadcast programming. It's just a technology, it's not a way of doing business.
Nearly fifty percent of all graduates come from the bottom half of the class!
Here's a good overview of the positives and negatives of spread spectrum modulation:
Spread Spectrum Rule Recommendations in Amateur Radio
That makes me curious... if WE aren't sending out directed transmissions to other stars on the 21cm line, why do we think that alien civilizations would be?
"Destroy science and religion. Science would re-emerge exactly the same; but not religion." - Penn Jillette, paraphrased
Ok, so there is a limited amount of Spectrum. Can you explain why, then, the amount of "public" spectrum is FAR FAR LESS than the amount of "public" parks in the United States ??
.. 20 Ghz, we have about 250 Mhz of public space. In other words, only about 1% of this spectrum is publically owned !! The rest has been usurped by your federal government, in the same way that they damned the grand canyon, flooded the HetchHetchee Valley of California, and any number of other federal abominations done for "The good of everyone !!!" (yeah, because the benefactors made huge campaign contributions, that's who is "everyone")... like RCA and Sarnoff ... sheesh.
:
In the 2.4 Ghz band we have 83 Mhz of spectrum.
In the 900 Mhz band we have 26 Mhz of spectrum.
In the 418 Mhz band we have ?? Mhz of spectrum.
In the 5.7 Ghz band we have 125 Mhz of spectrum.
In total, from 0
If we sold LAND the way we sold SPECTRUM, then the sale would be something like this
How much am i bid for all the rivers in america?
How much am i bid for all the valleys in america?
The fact is, cellular technology makes modern spectrum auctions STUPID AND IDIOTIC. Modern spectrum should be sold ONLY WHEN ATTACHED TO A PIECE OF LAND BENEATH IT. To do otherwise is to GROSSLY waste public resources.
I don't think anybody is claiming that this increases the total available bandwidth. What they are claiming is that it makes more efficient use of the available bandwidth by making formerly unusable bandwidth usable.
Of course you didn't look at any of the spectrum above 20GHz? Is
this because of cost/feasibility or just information available to
you? Above 300GHz nothing is licensed. Of course once one reaches
a high enough power level regulations come into play like with lasers
which are in the THz(?) range.
Unfortunately on the lower frequencies they cannot be attached to
the land beneath the expected coverage because of propagation issues
which may cause interference in another cell or plot of land. Once
one reaches a high enough frequency (above the 300GHz range, again
possibly in the THz range) it can be land area specific because of
specific attenuation by the atmosphere. This could then be used
to create thousands/millions of tiny cells with a very large amount
of bandwidth, since bandwidth available ultimately increases with
frequency, that would not cause intereference with each other because
they would be land area specific.
According to a conversation I had with Robert Pepper, entities in Europe owning spectrum can't lease them like in the U.S. With 3G spectrum being so expensive in Europe, UWB could bypass the regulation issues that may take forever to to fix thus jumpstarting the 3G wireless efforts. No wonder why Intel is pushing 3G efforts, to sell more microprocessors.
Because if you're trying to contact other civilizations, the 21 cm line makes sense. It's a scientifically interesting wavelength (Neutral hydrogen has a forbidden line at 21 cm) and the Universe is basically transparent to it.
The reverse argument, that we don't transmit at 21 cm, why should they, which implies if we aren't trying to contact them, why are they trying to contact us, is a valid criticism. I think SETI has basically acknowledged that unless an alien civilization is trying to contact us (or any other civilization), we won't contact them. It's fairly evident that within a few years, "leaking" radiation from Earth will be indistinguishable from noise, so we can expect other civilizations did the same.
This is why if SETI fails, it does not imply there aren't any other civilizations out there. It just implies that none of them are far more gung-ho about contacting other civilizations than we are.