[HN Gopher] Closing in on the "perfect code" (2004) ___________________________________________________________________ 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). ___________________________________________________________________ (page generated 2023-04-23 23:00 UTC)