Questions tagged [antenna-modeling]

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

Filter by
Sorted by
Tagged with
2
votes
2answers
72 views

Modelling a “fan dipole” or “fan inverted vee” using EZNEC - unexpected result

I plan to put up a "fan inverted vee" but for various reasons I will not be able to take it down, adjust wire lengths, put it up, test, etc: I will basically have to cut the wires, put it up and leave ...
1
vote
1answer
43 views

Modeling a multiband Yagi in 4NEC2?

I tried to model a multiband yagi. I added radiators for 10-15-20M, and reflectors spaced .15 wavelenghts away. This gave a nice result with three sharp dips in SWR in the 10-15-20M center frequencies....
1
vote
1answer
73 views

How to model my rooftop vertical on 4NEC2?

A few months ago I built a coil loaded vertical, and put it on my rooftop. My roof is made of corrugated metal, so I connected GND to it, to act as a ground plane (or is it a counterpoise?). With some ...
5
votes
2answers
140 views

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 ...
3
votes
1answer
115 views

Do Far-Field Radiation Patterns/Gains of NEC Software Accurately and Always Show the E-M Fields “Launched” by Vertical Monopoles?

Judging from posts on the Internet, this belief commonly is considered to be valid. But what is the correct answer?
2
votes
1answer
69 views

Convert NEC antenna file to .out-file for Wattwächter

I've just wrote a NEC Antenna file of my longwire with xnec2c on Ubuntu. To calculate protection distance with Wattwächter, I need an .out-file. Protection distance means the safety distance for human ...
4
votes
2answers
89 views

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 ...
3
votes
0answers
53 views

How to simulate two antennas in 4nec2

I need to simulate 2 helix antennae placed side by side, and see the resultant radiation pattern. But after adding the second antenna with a separate and when I try to simulate 4nec2, only simulated ...
5
votes
1answer
84 views

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 ...
0
votes
1answer
231 views

ADS Simulation: How to model an antenna in a simple rectifier circuit?

As titled, I'd like to explore the output power of a simple diode-based rectifier circuit, excited by an antenna (assumed to be 50 ohm impedance). Please give me some advice as to how to do this. It ...
1
vote
1answer
306 views

Raising height of inverted V by 2 meters

Now that I have a working G5RV Jr. and have had some good luck with DX (Croatia and Venezuela on 20m, Morocco on 40m from Michigan at 100w output), of course I want to mess with the configuration. It'...
2
votes
1answer
78 views

How to consider the influence from the PCB that a small antenna is mounted on?

The small antenna itself has an $S_{11}$ of -3 dB around MICS band (verified with simulation and network analyzer). In application, the antenna is mounted on a transceiver PCB of 30*15*0.8 mm which ...
2
votes
1answer
891 views

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 ...
3
votes
1answer
302 views

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.
5
votes
2answers
820 views

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 ...
6
votes
5answers
4k views

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 (...
1
vote
1answer
125 views

4NEC2 - Antenna outside Pattern

I am very new to 4Nec2 and need to do a simulation of a half-wave dipole antenna for 433 MHz. I've read a couple of tutorials and I understand most of it so far, still, my simulation doesn't make ...
3
votes
2answers
506 views

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 ...
2
votes
1answer
230 views

How do I simulate a receiving antenna in EZNEC simulation tool?

I have a situation where I need to find receiving antenna impedance when it’s $\lambda/2$ distance from the transmitting antenna. Both are dipole antennas. Is it possible with EZNEC?
3
votes
3answers
4k views

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 ...
7
votes
2answers
627 views

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 ...
4
votes
1answer
708 views

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 ...
2
votes
1answer
1k views

Is there a 4:1 current balun model for 4nec2?

I don't seem to be able to find the data to enter a 4:1 current balun in the 4nec2 software. Has anyone found or written one? I am building a 75 Ω fed OCFD and need to model the radiated patterns, ...
9
votes
1answer
147 views

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 ...