> "Trellis coded modulation got this rate up to 50 kilobaud by the 1990s" Not quite, and an interesting story that fits these engineering maxims better than you might think. An analog channel with the bandwidth and SNR characteristics of a landline phone line has (IIRC) a Shannon capacity of 30-something kbit/s, which was closely approached with V.34, which used trellis coded modulation plus basically every other cod…
Not quite, and an interesting story that fits these engineering maxims better than you might think. Huh? The SotA for dial-up modems in the 1990s was indeed 56 kbps, achieved with various encoding and compression hacks in both domains including trellis coding. Weirdly enough, you can apparently still buy them from US Robotics: https://www.usr.com/products/56k-dial-up-modems/
Akin's Laws of Spacecraft Design (2011) [pdf]
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Re: Akin's Laws of Spacecraft Design (2011) [pdf]
#112> "Trellis coded modulation got this rate up to 50 kilobaud by the 1990s" Not quite, and an interesting story that fits these engineering maxims better than you might think. An analog channel with the bandwidth and SNR characteristics of a landline phone line has (IIRC) a Shannon capacity of 30-something kbit/s, which was closely approached with V.34, which used trellis coded modulation plus basically every other cod…
Re: Akin's Laws of Spacecraft Design (2011) [pdf]
#113> "Trellis coded modulation got this rate up to 50 kilobaud by the 1990s" Not quite, and an interesting story that fits these engineering maxims better than you might think. An analog channel with the bandwidth and SNR characteristics of a landline phone line has (IIRC) a Shannon capacity of 30-something kbit/s, which was closely approached with V.34, which used trellis coded modulation plus basically every other cod…
Re: Akin's Laws of Spacecraft Design (2011) [pdf]
#114Earlier quoted context omitted.
> Would you assign a large sum of money to a group that cannot present their design clearly, neatly, and concisely? If they are struggling even with that, would you trust them to be good at actually designing a spacecraft soundly, economically, and in a reasonable time? This mentality seems very US-Amercian to me. > "If you can't explain it to a five-years-old, you likely do not understand it yourself", said one of t…
What problem in the physical world does a knowledge of A1 homotopy theory enable you to solve?