4nec2\exe” folder, in your Word or Wordpad text editor. Other recommended sources for NEC related informations are the Nec-2 and Nec-4 user-manuals and . 4NEC2 is a freeware antenna simulation software program. The program can be used to model an antenna, and then determine through. Antenna Modeling With 4NEC2. Presented to HOTARC. By Craig Weixelbaum. May 22, Basic Modeling Approach using 4Nec2. The goals of this
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Get the optimum final value performing the convergency test shown if the next section.
Designing an antenna system with tough geomertrical and environmental constraints is tough. Then start modeling your antenna 4mec2 Normally, the results will be similar to those one may find in the textbooks.
Now that would be an antenna!
4NEC2 freeware antenna modeller and optimizer Product Reviews
You have to select View, then, select far field pattern. If this rule is not observed, the model probably has defects in the specifications of the generator or maybe the generator is located in the wrong place.
His work in 4NEC2 will non-the-less continue to serve hams indefinitely.
If the wire is not paralell to the ground, the height of the end nearest to the ground will be considered. The X axis will be used for the front-to-back direction.
This section shows some advices and rules of design about the characteristics of the generators, loads and transmission lines to be used in the simulations. The ground is simulated in the XY plane and the Z axis represents the height over the ground.
American Radio Relay League. In a model with several wires, it is advisable not to connect short segments with long segments [Ref. In all the radiation patterns calculated with NEC-2, the gain is expressed in dBi.
The Other Edge of the Sword”. Program Description – Code”. Terminology used in NEC Or balance all of these in weighted format. The default plotting routine is fully featured, and, the data array can be saved.
EA4FSIT1 :: Notes on antenna simulation using NEC-2
An elevation of 90 degrees will correspond to the perpendicular to the ground plane. Two wires may not meet in the intermediate points of any of their segments [Ref. One way to simulate a connection of a vertical wire to the ground is by means of a virtual plane of at least eight radials [Ref. Technical Articles Radio Propagation: NEC-2 lacks the capacity to model dielectrics, such as underground radials or antennas with electrically isolated wires twin-lead J-pole, twin-lead folded dipole [Ref.
EA4FSI-28T1 – Technical Articles
The Sommerfeld-Norton S-N is the most precise ground model, with the highest computational cost and is the best method to simulate horizontal wires very close to the ground. Restrictions related to the minimum and maximum radius of the wiresas a function of the length 4nev2 the segments, may be imposed in some programs. The perfect ground consists of a perfect electrical conductor ground plane, without losses.
Therefore, the number of segments employed must be changed with the frequency, or must be calculated in order to be above the recommended minimum corresponding to the highest working frequency lower wavelength [Ref. This problem can be minimized making the manuak of the wires to change in a series of steps through several additional intermediate wires [Ref.
Version 2 Aug Results of the average gain test in a 4Nec2 model. This section shows other advices and rules of design not related to the previous sections: In order to avoid errors, it is of interest to observe the following general rules while designing simulation models: Geometry of the models.
Regarding the minimum length of the segments Lsminin the different references checked the following restrictions related to the diameter of the wire and the wavelength have been found: When I first 4nex2 this program I almost put it in the too hard basket. My problem was to get a reasonable, low-cost m attic antenna in a crowded urban setting with metal surfaces everywhere.
Those notes are a collection of advices and rules of design to perform simulations of antennas with programs based on the NEC-2 algorithm. Variety and Modeling Hazards. The generator would see load in one of its poles and open circuit in the other one, so theoretically there would not be current generated in any way.
The MININEC ground model assumes a perfect ground for the computation of the currents and changes to a dielectric ground for the computation of the far field patterns ground without losses. Geometry and operative aspects of the simple modes of ionospheric propagation. Using just one of the tests does not ensure that the model will be adequate [Ref. If two wires of different diameters join in a point, the results of the simulations may not be precise [Ref.
AntenneX Online Magazine, However, scripting the 4NEC2 code in Notepad wasn’t bad at all. The program has two parts. QSTFebrero In order to make possible the comparison of the radiation patterns os different antennas in an easy way, it is advisable that all manusl models are represented geometrically agreeing with a set of general conventions.
NEC-2 does mwnual allow to model underground wires [Ref. And, once they are translated, you can modify the card format, and, turn them into variable based models for optimization. The coordinate systems may be different among the different programs based on NEC It took 24 iterations in about 4 seconds.