RF design software, a follow up from VNA advice - Page 1
Forum section: electronics / testgear

author: KJDS
author_rank: Super Contributor
timestamp: October 31, 2014, 08:08:35 am
content: In the VNA advice thread was this and I think it's probably worth its own thread. No idea which forum it should be in so I've left it in test equipment.Quote from: TerraHertz on October 31, 2014, 01:39:35 amSo here are my experiences.The Rf design software that I've used most is Microwave Office, MWO from Advanced Wave Research. It's a big, complex, very powerful modular suite. The basic module is a linear analysis package and the component library includes most transmission lines and board traces, coupled lines and junctions and well as passives and the ability to use S-par files for everything from transistors to measured components. There is a non-linear module that when you have the appropriate licence is a seamless part of the suite. This allows harmonic balance analysis of non-linear networks. Suitable models are available from the makers of most high power RF transistors. The EM package also fits seamlessly, it is a 2.5d package that is fine for simple circuits but I've never tried doing anything complex with it. I believe that Sonnet can also be integrated. The layout package is easy to use for simple microwave focused tasks and because of the object oriented structure, then if you change a length in the schematic the length in the layout and the analysis results all change at the same time. There is also a system simulator when you want to work on say, a complete transmitter with complex modulation but I've never used it seriously. MWO is very easy to use, I can teach someone the basics in minutes and it's intuitive enough that most engineers just need pointing in the right direction. There are also assorted synthesis tools for filter design etcADS is the Agilent offering. Overall capabilities are similar to MWO with slightly more systems analysis capabilities. The 2.5D EM solver is Momentum which I have used a lot for complex matching problems, mostly with high power transistors where there is a need to match from an impedance for 0.5 ohm up to 50 ohms. It is very capable, and also very bug ridden. Most bugs can be worked round, but I hate having to fight the software. It is not as intuitive and the layout, synthesis and analysis can all be in different states at the same time.APLAC is from the Helsinki university of technology and was a collaboration with Nokia. It is capable of doing anything, including driving the user insane with it's complexity and difficulty of use. I've not used it for about 12 years and it's rarely found outside Nokia. It was bought out by MWO a few years ago as they had some good technology and MWO had a great interface. It's possible that there are some legacy systems still running.Eagleware Genesis. Annoying, buggy but capable with poor support when a real issue came up. Fine for basic analysis but models such as baluns had some real issues which Eagleware refused to rectify. It was bought out by ADS some years ago and is still offered as a stand alone suite. I've not used it in almost 15 years so am not up to date with it.The above are all expensive professional systems, though being modular it's possible that MWO linear only could be within the reach of a wealthy hobbyist.The best freeware I've used is RFSim99. It's fine for simple linear problems and can include S-par files but I believe it won't run on 64 bit machines.If you want a 2.5D EM solver then Sonnet Lite is free and capable of tasks of moderate complexity.What I will say is that analysis software is very easy to misuse. A circuit should be calculated or synthesized and then analyzed. It is well worth putting together a spreadsheet, Matlab or Mathcad file with any calculations that you are likely to repeat. I prefer Excel as I know I will always be able to use in on any machine I have to use. If you're good with Matlab then the maths will be easier there. So if I want a 4dB resistive PI attenuator, or a seventh order chebychev filter then I only need put in the design parameters to get the component values. That's far better than putting in some random component values and tweaking and optimizing the design to get acceptable performance.

author: Mr Simpleton
author_rank: Unknown
timestamp: October 31, 2014, 04:51:57 pm
content: Have been using Genesys since version 3.3 (and DOS) up to version 2012... and like it. Yes the non-linear stuff seemed to be an add-on... but what was great with Genesys was its filter design wizzard. The linear simulator was as stable as most other!Even though MWO is moving in at the office I still hold on to Genensys. RFSim99 is really great and is often more than enough for those simple linear circuits. For those who want to use RFSim99 you need to install (extract) on an "old" XP 32 bit system. Once done, just copy the whole folder and it should run perfect on newer W7 systems, just verified it do start on my W7-64!!

author: TerraHertz
author_rank: Super Contributor
timestamp: November 02, 2014, 04:06:15 am
content: Quote from: KJDS on October 31, 2014, 08:08:35 amThanks for this. I don't think I have anything useful to add, but I'll be reading.

author: Melt-O-Tronic
author_rank: Frequent Contributor
timestamp: November 02, 2014, 04:43:51 am
content: I stumbled across emGine Environment recently while trying to find something free or inexpensive to design striplines. I haven't had time to download it or play with it (and not sure I'm up to the task anyway), but was wondering if anybody had any thoughts on it.http://www.petr-lorenz.com/emgine/index.php?option=com_content&view=article&id=44&Itemid=53

author: G0HZU
author_rank: Super Contributor
timestamp: November 02, 2014, 02:46:33 pm
content: I've only skimmed the website but that EmGine simulator looks very promising.I've not tried using it but I do have a few concerns what might happen in the future if it proves to be popular and successful.I would expect one of the big players in the simulator world to buy the rights to it. Hope I've worded that OK but you get the idea...At work I use Sonnet for EM stuff and it is easily the best EM simulator on the market. However, it's GUI does look very, very dated and clunky and it's very easy to dismiss it as inferior in this respect. To avoid the clunky Sonnet interface as much as possible I always use its basic simulation engine as an addon to Agilent Genesys. This means I get the benefit of the GUI of Genesys to do schematic entry and PCB layout and also the benefit of the accuracy of Sonnet when it comes to EM simulation of the design layout. The results of the combined Sonnet + Genesys simulation are graphed in Genesys.

author: dannyf
author_rank: Super Contributor
timestamp: November 02, 2014, 03:15:49 pm
content: QuoteHow about Genesys?

author: KJDS
author_rank: Super Contributor
timestamp: November 02, 2014, 04:02:38 pm
content: Quote from: dannyf on November 02, 2014, 03:15:49 pmSometime ago, around 2005, when MWO was starting to become popular, Agilent realized that despite having the market leading design software, most of their design team had left for MWO, it had management issues and Genesys was also taking some of their customers. They needed new design blood and someone to oversee the design process to improve their working practices. Their solution was to hand Randy Rhea a big pile of money for Eagleware (which was his company that produced Genesys) and he helped with their software. I've not used any of the Genesys tools in a long time. They used to be a reasonable budget offering but I understand that has now changed.

author: nctnico
author_rank: Super Contributor
timestamp: November 02, 2014, 06:15:15 pm
content: Just to sidetrack the topic a little:During my EE study for a bachelor's degree the topic RF has not been touched at all. Unless you would call transmission line reflections RF. I have found it very hard to get into RF because there is very little information on how to calculate things like hairpin filters etc. In many cases you get directed to the ARRL handbook which IMHO is just shaving some topics by telling 'build it like this and it works' but no in depth theory. The best book for designing RF filters I found so far is 'Microstrip Filters for RF/Microwave Applications' by Hong and Lancaster but finding out it existed was more luck than wisdom.Maybe some of you could add other book references which allow the reader to design RF circuits from scratch.