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This is an enormously useful insight for my use case. With this information, along with some of the other tips here, I spent several hours this afternoon with my NanoVNA and my portable adjustable

my experience likewise. It sort of depends on what "ground" is and how close you are. NEC4 does much better with antennas that are close to or touch the soil. But NEC2 does pretty good, if you're

Back in 2011, I used something called FEKO Lite to model a PCB bowtie antenna with a tapered matching feedline that had to function both as an antenna and a rudder for an autonomous submarine.

OPENEMS.DE Open EMS is to HFSS as Linux? is to? Windows Produced by a community of EE and software geeks. Be sure to download the tutorials. Like HFSS, it has quite the vertical learning curve.?

Sonnet USA supplies a far-field radiation pattern program as an option on all versions except the free SonnetLite. It probably costs an arm and a leg to get it, though. I've been using SonnetLite for

Thank hou for correcting me. DaveD

Jim, I've not experienced that problem when the model is properly set up. I've designed and constructed many antennas from HF through L-band and the 1.42 GHz deep space neutral hydrogen emission using

NEC is not frequency limited - you can model wire antennas at 30 GHz if you like. The problem is that nobody builds wire antennas at 10 GHz - the losses get high. Then you're doing microstrip patches,

In general Method of Moments (MMANA, NEC and programs that use NEC) is not a great way to model surfaces like patches. If you're making simple patches, then the equations in textbooks like Pozar or

I believe that NEC derivative modeling software only goes into the 300 MHz range. The two higher-frequency software packages of which I am aware are CST Studio and Comsol Multiphysics. CST offers a

None! They do wire type antennas only.

I am considering learning to use one of these programs to model 2.4 GHz PCB antennas. Are there some that are better at that frequency range?

Can you provide more information? NEC *defaults* to 300 MHz (1 meter lambda), it's basically just geometry. I've done a *lot* of NEC modeling and never seen errors like that. I *have* seen errors due

NEC2 is free, as is 4nec2, as is MMANA. NEC4 (or NEC5) require a one time license fee to Lawrence Livermore. Yes, one of the huge advantages of EZNEC is the modeling assistance in the manual, which is

Be aware that EZNec with the built-in NEC engine doesn't work well on higher frequencies like 50MHz.? The resonant point is off by a couple hundred kilohertz.? The latest LLNL engine gets it right.

I only start to know EZNEC well. If you install EZNEC, it files the manual (in English) in the form of a Word file. It is huge because the author explains a lot about good and bad modeling as well as

At HF (1.8 through 30 MHz) the influence of adaptors is pretty minimal. Above that, yes, you need to cal. with the adaptors and the appropriate cal. kit(s). This should not be considered a 1 or 0 hard

I've never really progressed past creating an input deck using the text editor and viewing the results in the geometry screen. One of the members at digitalhome.ca wrote a python optimization script

They're basically the same NEC engine underneath - So if you have EZNEC or 4nec2, you have a UI that builds a model and hands it off to the NEC2 engine, which does the computation, then the program

How do the results of the two compare? Zack W9SZ