[HN Gopher] Closing in on the "perfect code" (2004)
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Closing in on the "perfect code" (2004)
Author : akhayam
Score : 42 points
Date : 2023-04-23 17:38 UTC (5 hours ago)
(HTM) web link (spectrum.ieee.org)
(TXT) w3m dump (spectrum.ieee.org)
| capitainenemo wrote:
| 30 years ago? What took so long for broad adoption? Patents?
| _edit_ Article doesn 't elaborate on why that might be, but it
| does note: "an alternative that has been given a new lease on
| life is low-density parity check (LDPC) codes, invented in the
| early 1960s by Robert Gallager at MIT but largely forgotten since
| then...Now researchers have implemented LDPC codes so that they
| actually outperform turbo codes and get even closer to the
| Shannon limit...Another advantage, perhaps the biggest of all, is
| that the LDPC patents have expired, so companies can use them
| without having to pay for intellectual-property rights."
| mturmon wrote:
| Turbo codes were used in the Mars Reconnaissance Orbiter (2005
| launch) due to work by JPL telecommunication researchers. (http
| s://en.wikipedia.org/wiki/Mars_Reconnaissance_Orbiter#Te...)
|
| Edited to add an early link to more granular technical work:
| https://ipnpr.jpl.nasa.gov/progress_report/42-120/120D.pdf
| giobox wrote:
| Not an expert, but I've encountered Reed Solomon error
| correction extensively in my career, and this seems to be
| replacing RS applications? I wouldn't be surprised if there was
| a fair amount of inertia to overcome given how widely used and
| how well RS worked for a very long time. RS was critical for
| things like ADSL data transmission over POTS and other similar
| large scale applications.
|
| The wikipedia page for RS suggests some RS implementations are
| now "being replaced by more powerful turbo codes".
|
| >
| https://en.wikipedia.org/wiki/Reed%E2%80%93Solomon_error_cor...
| akhayam wrote:
| Just adding some extra color: Turbo codes did get instant
| traction in the industry once the academics actually
| "believed" them to be true. So the friction came from the
| academics and not the industry. Today, every communication
| system you are using are relying on Turbo codes in some shape
| or form.
| topaz0 wrote:
| Note that the article is almost 20 years old, so it is more
| like 10 years for industry adoption.
| Yoric wrote:
| Unfortunately, one of the common scenarios when it comes to
| percolating results from academia to industry is the following:
|
| 1. Academics make discovery/invent something.
|
| 2. Academics attempt to convince industry to adopt discovery.
|
| 3. Discovery is laughed out of industry as "impractical",
| "academic", etc.
|
| 4. Academics teach discovery to their students.
|
| 5. Students get into industry.
|
| 6. Students get into position of tech leads, architects, etc.
|
| 7. Students demonstrate the use of discovery.
|
| (by then, 30 years have elapsed)
|
| e.g. garbage collectors, type systems, threads, distributed
| systems, message passing concurrency, actors, JITs,
| metacompilation, machine learning, functional programming...
| pipo234 wrote:
| > 3. Discovery is laughed out of industry as "impractical",
| "academic", etc.
|
| To be fair, sometimes academic inventions _are_ impractical
| given the technical landscape du jour. They only become
| feasible as technology and society progresses, say 30 years.
|
| Also, your observation does not mean _any_ invention is
| meaningful (and will eventually be recognized as such). I for
| one, learned a bunch of "impractical", "academic" nonsense
| too in university.
|
| But yes, I think as a whole, your 7 points observation as a
| whole is very much at play in the Turbo Codes case. Yes.
| Yoric wrote:
| Fair enough.
| nunuvit wrote:
| While that does happen, that's not the reason.
|
| Article says it was used in satellite links and deep space
| networks before it was cool. Those applications had hit their
| technological limits and no one was making something new they
| could buy next year, so they had to do it themselves.
|
| Contrast that with phone networks being able to rely on the
| next G coming out. Now we have 5G, but it's 5G with an
| asterisk, so it's time to look for a new approach.
|
| Same with Moore's law. The semiconductor industry was really
| focused on smaller transistors until they started getting
| close to the physical limit. Then suddenly everyone is
| talking about chiplets and other ideas that had been around a
| long time but weren't mainstream.
|
| Changing approach requires a lot of coordination and carries
| a lot of risk.
| HopenHeyHi wrote:
| 0. Science Advances One Funeral at a Time
| readthenotes1 wrote:
| 1.5 More established academics deride, scoff, and do their
| best to extinguish this new work.
| hinkley wrote:
| 4.5 some of the less arrogant academics internalize the
| complaints about their solutions and iterate on it to make
| it 20% easier to use and/or 20% better in practice, making
| the cost of change more attractive.
| Yoric wrote:
| I'm sure that this happens.
|
| When I was an academic, I never encountered (or heard of)
| such situations, though.
| bheadmaster wrote:
| Wait, what exactly is metacompilation, and in what form is it
| used in the industry? I've tried searching the internet, but
| only found theoretical explanations I'm too tired to parse
| right now, and something about yaks and bisons.
| akhayam wrote:
| In 1993, two unknown French engineers claimed to have found a
| coding scheme to provide virtually error-free communications at
| data rates and transmitting-power efficiencies well beyond what
| most experts thought possible. Nobody believed them and set out
| to find the error in their paper... There was no error.
| jgalt212 wrote:
| > key to the next generation of multimedia cellphones
|
| How is perfect data transmission a make or break feature for
| lossy compression and transmission of audio and video?
| rrwright wrote:
| The article is from 2004.
| dang wrote:
| Year added above. Thanks!
| akhayam wrote:
| Yes, wanted to share an interesting story of how great ideas
| can come from folks who are not the most popular names in a
| field. I feel the same will happen with AI now.
| Sniffnoy wrote:
| The thing to note here is that it's customary when posting an
| old article to HN to include the year in the title in
| parentheses.
| eikenberry wrote:
| https://en.wikipedia.org/wiki/Turbo_code
| esprehn wrote:
| This should be tagged (2004)
| dang wrote:
| Added. Thanks!
| zokier wrote:
| See also Fountain Codes, e.g. RaptorQ:
| https://en.wikipedia.org/wiki/Fountain_code
| akhayam wrote:
| Erasure codes are a work of art for storage use cases, but not
| as broadly relevant as, say Turbo codes or space-time codes
| (like Alamouti codes).
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