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Questions tagged [antenna-modeling]

Use for questions about using antenna modeling software to simulate an antenna system and determine its gain and radiation pattern.

The correct spelling in English-speaking countries outside the US is antenna-modelling.

With modeling software, you can determine the pattern, feed point impedance and even the SWR of your antenna system before cutting one piece of wire or one tube of aluminum. This can save an awful lot of tree and tower climbing.

Antenna modeling used to be the domain of scientists and engineers with very expensive antenna ranges covering acres and acres of land strewn with expensive equipment. However, with the proliferation of personal computers and affordable (even free) software, antenna modeling has become a popular amateur activity.

From http://www.arrl.org/antenna-modeling

Popular antenna modeling software

39 questions
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Antenna modeling on non-uniform terrain

I'm interested in modeling the radiation pattern of wire antennas for hf before I invest the resources necessary to erect the antenna. I'm familiar with tools such as 4nec2, but from what I can tell the ground is modeled as being flat. However, at…
W5VO
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Does mounting a ground plane antenna upside down change the takeoff angle?

A typical gain pattern for a quarter wave ground plane antenna is: Image from a similar question and see watermark. For a situation where the signals of interest are below the antenna in elevation (e.g. antenna on a hill/mountain), would mounting…
hazzey
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Simulating two antennas (transmitter and receiver) using 4nec2 tool

I am trying to find near field mutual coupling affects between two antennas - one being transmitter and other being receiver. The receing antenna is fed with very little voltage (I think, if I don't feed any source, then nec tool inserts default…
Shiva Mudide
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4NEC2 - Radiat-eff. vs. Radiat-power

In the output from 4NEC2 the input power is 100 W. On the left, in blue text, is Radiat-eff. which equals 15.41%. On the right is Radiat-power which equals 94.88 W. I would expect either the first to be 94.88% or the second to be 15.41 W. Why the…
user34299
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How to produce a NEC antenna file (and what software to use it with)?

So I'm really trying to get to grips with antenna radiation patterns, and more importantly things that are to close to the antenna that might interfere. I've downloaded Qantenna and 4NEC2 to try and model my antenna and see what I can do, however…
FraserOfSmeg
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Modelling a folded dipole

I am looking at using NEC to model a $0.5\lambda$ rectangular folded dipole, for closely spaced larger sides (choosing a separation of $0.01\lambda$). In Antenna Theory, Analysis and Design by Balanis, the folded dipole is touched upon, and an…
pymekrolimus
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How to model passive elements when simulating an antenna?

So I started writing an antenna simulator program to design antennas for my needs. To calculate the electric field vector at every point, I split the active element of the antenna into a large number of smaller parts and the calculate the electric…
atomd
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Correct number of elements in 4nec2 antenna simulation

I am designing a 1.25-wavelength dipole antenna with the 4nec2 software. What I noticed is that the input impedance of antenna is changing greatly when I change the number of segments. How many segments should I choose?
Shiva Mudide
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How to correctly model a small helix antenna

I am getting weird results trying to model a small 433 MHz helix antenna similar to this one with 4nec2: In particular I am not able to obtain a resonable SWR value. This is the antenna an example of the nec file. CE SY L=0.0205 'Length of helix SY…
stenio
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4NEC2 radials & grounds

Teaching myself 4NEC2 and have most of it under control, which is good. Regarding radials & grounds, i've been learning the "rules" NEC(2) has, summarised below. 4.1. Free space. In the simulations in free space, logically there is no…
t252
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Basic antenna matching theory?

I'm fairly new to antenna matching, other than having built a base loaded vertical. I'm also new to EZNEC and I tried to simulate an horizontal loop. I arbitrarily chose a 10x10M loop, so I added 4 wires, 10M each, 5 segments each (20 segments max…
hjf
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How do I specify that wires are connected in 4NEC2?

I've been trying to get acquainted with the 4NEC2 antenna modeling program. Perhaps this is obvious, but it's not clear to me that wires with one end in the same place are connected. I'm attempting to model a simple quarter-wave antenna with four…
Rodney Price
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Mathematica notebook for NEC2 (NEC, Numerical Electromagnics Code)

Are there any open source Mathematica notebooks that interface with NEC2? I am primarily interested in plotting the NEC2 results from Mathematica.
ZJL
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Antenna gain vs. radiation efficiency in 4nec2

I'm trying to evaluate HF antennas for low angle performance to pick from a list of designs that will fit in my limited space. I'm using 4nec2 to simulate them and compare the patterns. When your simulated antenna has a low radiation efficiency, is…
hamateur_sandwich
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How to make ELF-ULF antenna myself?

I want to check the EM pulse between 3HZ-3kHZ with N9041B UXA Signal Analyzer,it seemed the only antenna I can use is Aaronia MagnoTRACKER,but the price is not affordable. Then I plan to make ELF-ULF antenna myself,could you pls give me some…
kittygirl
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