X-Authentication-Warning: delorie.com: mail set sender to geda-user-bounces using -f X-Recipient: geda-user AT delorie DOT com X-Original-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:from:date:message-id:subject:to; bh=Cm0uOXtgw6iY574oBsJVdcxt2H6j4xfMaGGvUlDzmnQ=; b=nu2i4pH+r4bnbMLH43jQRYDN0++l+UhbsHWvfrZ+XGfqzEPv8JNgj0WCpvYlYuvgub 5XS7zBJ6OQN2JLDFsH1DN9FaAbtDlTHrVk4F1kfrTMN/itaDtnSC3AIpFVcP/s03oNft 4bafO97iggG1rBbPstz7tKLD/P+JTmt0SBIYKU87ceOlvILP6Zeb4HUUTzR9nx8XilqD LOxRRdHGNVyp6BDtZCkYbhLy+juh0gmjkdelpmqkz+fA+/OzE8foTaNizgvyY36xYBk0 bOPQPe8pGACk9KC1L2ATCVZphdf3f4CjP2qU9YIOqxNOPggY/WYqTOoolR3NlOPBIkLt SHAg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to; bh=Cm0uOXtgw6iY574oBsJVdcxt2H6j4xfMaGGvUlDzmnQ=; b=bym5yOzFGnWKySsOpfCqQZV0rx6bz2cN9en9vqBLUKYLMd/Ma0N4htRpa1XO05tA9z GCmDua2JE5HHA0jA2melpZeleiDcLVX4UoPb2nreTzIcl6gVklbG4SB1tzLt65By9HDV T47iyHNkZCwZQ9xY0x+hqFqtT1/Y8JR0nvAVlxvaFJls6cRC1vZT5JofWGPy+TQPKOwL b5TVNwkPl67UsH32NXv0e/UlxbjlUtoRBNguG/i8KHgAsF0fXTZXpsTkRkClhOgcqziY SyOe6sN51Z91QIOMkyAZKOxLgc6zC63urm5XVplWC2w5se9EPgKyjsN46k6HlzZlHAsS hpSg== X-Gm-Message-State: AE9vXwN5x4f88+Sov2tZlTdZYKPu5TSUz5RcA7iwrUSxoW3EbWhuOuJGjwaBfQLyISevIJBup/vleEIO/D+RTw== X-Received: by 10.25.26.193 with SMTP id a184mr2663484lfa.219.1472613387402; Tue, 30 Aug 2016 20:16:27 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20160827013103.63bb0bdd@floyd.freeelectron.net> References: <57C09C3C DOT 7020708 AT xs4all DOT nl> <20160826171545 DOT 2bc54995 AT floyd DOT freeelectron DOT net> <20160827013103 DOT 63bb0bdd AT floyd DOT freeelectron DOT net> From: "Evan Foss (evanfoss AT gmail DOT com) [via geda-user AT delorie DOT com]" Date: Wed, 31 Aug 2016 03:16:26 +0000 Message-ID: Subject: Re: [geda-user] Microwave PCB layout simulation or How to eat all your processing power in 3 easy steps To: gEDA users mailing list Content-Type: text/plain; charset=UTF-8 Reply-To: geda-user AT delorie DOT com Errors-To: nobody AT delorie DOT com X-Mailing-List: geda-user AT delorie DOT com X-Unsubscribes-To: listserv AT delorie DOT com Precedence: bulk On Sat, Aug 27, 2016 at 5:31 AM, al davis wrote: > On Sat, 27 Aug 2016 02:18:11 +0000 > "Evan Foss (evanfoss AT gmail DOT com) [via geda-user AT delorie DOT com]" > wrote: > >> How does gnucap-verilog solve this? I thought verilog was just another >> language for describing netlists and schematic behavior. > > It is. Verilog as a netlist format is much richer than the spice > format. > > We have documentation on how to include the layout physical info in the > Verilog netlist. > > First cut is here: > http://gnucap.org/dokuwiki/doku.php?id=gnucap:user:netlist_import_and_export > > There is more detail and revisions in my FOSDEM presentation. > > >> How does that >> get us closer to testing a pcb level implementation of a Wilkinson >> splitter or a distributed element filter? I would think we would need >> FEM of some kind to extract the relevant properties of the layout and >> then process them for conversion into verilog? > > The first step is to transfer the data. Once the data is moved to a > format that gnucap understands, the gnucap project can take it from > there. Reading the rest of your email that seems mostly like moving to verilog is just a way of making the workflows graph simpler. Like verilog ams is one container that we could use in place of a few other ones. I like gnucap but I don't want it to be the only tool that plugs into the field solver stuff we add. Just like I would not want geda to only support gnucap as it's one simulator. I would really like this to continue with netlists as we have them. Xyce is a simulator that supports gEDA like it is a thing they are proud of. Xyce is also nice in that it works on distributed (MPI) environments. I want compatibility and the choice to use Xyce or Gnucap depending on the scale/type of problem. > More detail. ... > > There are two parts here. > > One part is making a netlist, comprised > mostly of transmission lines, or a more abstract device that is a > transmission line underneath. That is a simpler problem. > The other part is to parameterize the > transmission lines. Initially, the parameters can be geometry. There > are simple closed form equations to generate electrical parameters that > work well for simple structures. Getting this far is a big > accomplishment. I doubt it will help the microwave people who really need a field solver. > For more complex structures you need a field solver. > There are free field solvers available. (OpenEMS and others) We just > need to interface to them. Antenna's, distributed element filters.... If we follow your plan we would still have to take the output of openems and convert it back into an equivalent circuit for the transmission line model. Cray LC did this but it is both unmaintained (talked to the author) and closed source. I really like what you want to do and it would be *very* useful to me. > Hyperlynx actually uses a mix of field solver and closed form equations. Hyperlynx is of no real interest to me. That was just used in one example. > If what you want to see is radiation, you might be able to do it all > with the field solver. I would not want to do that. The processing power waste would be tremendous. > For signal integrity, they all do it as a 2-step process, with one of > the steps being a circuit simulator, usually not spice. Ok. Well we have at least two users who can make good use of a field solver on some antenna problems. Your solution already requires the ability to export pcb-* geometry to a field solver. I could join your project that is big and possibly get something done eventually or continue with this smaller mission and help make something that works now. Sorry but I am already committed to various things for pcb-rnd any way. -- Home http://evanfoss.googlepages.com/ Work http://forge.abcd.harvard.edu/gf/project/epl_engineering/wiki/ -----BEGIN PGP PUBLIC KEY BLOCK----- Version: GnuPG v2 mQENBFYy4RYBCAC183JomLtbdAlcKiaPDoVHq52LDmVmH75aiEc69m7YxDt54/ai VtYCAobbGVIyn3Hlz3uhF6LnPl/6Lm1VdnCfpwu3KQhCO6ds10ow2C30X4ohCqOd hCVg5C+ILmQkEffFrFODy3ji+PYTF4pADvHCWsTMv0hf0llwFOJsBCK6cl02IffE JPqy4PjM1nZ9HpzT84JBaG/4OGvTZ8SQ2yFUl265jagvygPTf88H1xpZHH1r8dB1 stjUHLmPH8AOyDgKxFchgGeDc3p/vJtgDDIXAFfDXG0NSRovLmtaQdGxe47Zf/go bXiEM7YL2WqQe5zfEA919JxkEwlDKYniOSVzABEBAAG0N0V2YW4gRm9zcyAoVGhp cyBpcyBteSBwdWJsaWMga2V5LikgPGV2YW5mb3NzQGdtYWlsLmNvbT6JATkEEwEC ACMFAlYy4RYCGwMHCwkIBwMCAQYVCAIJCgsEFgIDAQIeAQIXgAAKCRCIpQTcE8nN bbBaCACAm8pU5lG1ev2Fsw68Axtcl57SJrYieqX96c3YuYH9JpqMqJRnd9nDKw9X tQuvuH7tUk0VbOaDqReOYJVI/4c5wb9AaOFp6K2DUcupq6XhgXpvz3HzoPwjAdIj XuQzdRUx5+innTJrSkGuBYW/CZ2zqEx4xfLlq4rO0hoTUMR8QVp2cCrkw6BT0m86 APIw/ZnjoxM8IEzr7MxfRIg3qpzrZk28rmhx+k78Jyk61UhwcCPGIm/pjUopTwYJ 3YBdRB2cYD2aN7A1JVf5cRmSQYooHBGpH0kYvomGk97PKqypVuJ7OpG9xM58wUcC qUVt9hKlePLzP8csYjt8onqI7qIIuQENBFYy4RYBCADlH8spG3WkCx62vB5mr5Z0 SCDd/RcyA4A5y5EOj5KurQkrSWpgi9Ho1yKruMJ6blQR2qkc66KqH9pnXDm/ZI1M K/wdW3ngETxBmXoozzFMT89aEWIVR5/PFodWK1elekE9iJxACuR98Zg2QttTD3x8 A9w8VEyMLOXcDTrPFpHegMKswFBg5iuMulAdXAoGejWTI3n+qKFpabHm2Lfs6wjk 5rjucpTdeFK6UeWF1xAvNxXibuu5BlGwv53930qIXRwO/Gn2Rh5DXWxKU2fEIme/ xgQQmIsDeUoWbfybdjw/x7Q0LW4mINiLDQcGHHRQKFIxbAJCT3USPLGh5xwE9/Er ABEBAAGJAR8EGAECAAkFAlYy4RYCGwwACgkQiKUE3BPJzW0uYAf9Hf30n8tM3mR2 Zo6ESE0ivgdgjaJtAWrBUx7JzAzPjBnBOlNnu5Y9lVEqetvUPH6e3PvaHYUuaUU8 0HwxuKBW9nUprgV6uIu1DZmlcp+SxpbuCy7RDpNocRLNWWFMaYYzznmTgfnTgD4D gCq8Mf1mcfrluTkOAo+QNqbMfl1GISClopRqxVuAo59ewgMnFujwgd8w12BwWl24 CzqOs5HqcUslePj+LzcjSNgVCklYwKl+0dsb/fctMOCtHodwqm2CBJ+zydvNmYkD fxda/J91Z1xrah5ec++FL0L4vs+jCiIWJeupJFKlr1hCMZiiGH7W554loK5l4jv3 EY347EidAw== =Ta4p -----END PGP PUBLIC KEY BLOCK-----