MMANA-GAL Antenna Modeling ProgramAuthor: Makoto (Mako) Mori JE3HHT © 1999-2000
Gontcharenko Gary DL2KQ-EU1TT developed and released English versions of MMANA in 2001-2002. Nobuyuki Oba JA7UDE wrote an English user manual in 2001. Software beta testing was provided by a group of fellow amateurs.
MMANA is an antenna analyzing tool based on the moment method introduced in MININEC (Mini Numerical Electromagnetics Code) Version 3. MININEC should not be confused with NEC, which is a large antenna analysis program written in FORTRAN and designed to run on main-frame computers. Early versions of MININEC were written entirely in BASIC and the computation engine source code was published as a PDS in MININEC Version 3. That BASIC source code was ported to C++ and compiled to provide faster and more memory-efficient computer execution. A graphical user interface also was added that makes MMANA much easier to use than MININEC version it was ported from. (Some portions of later versions of MININEC are written in FORTRAN.)
Most professional antenna modeling is now done with later versions of MININEC that have important improvements. However, Version 3 has one big advantage compared to later versions. It costs you nothing! Furthermore, even though it is outdated, its capabilities are adequate to model most antennas commonly used by amateurs.
The radiation field produced by a transmitting antenna system having any known arbitrary current distribution can be found by adding the separate fields produced by elementary lengths of thin conductors with each elementary length treated as a very small radiating doublet antenna. In adding the contributions to the total field that are made by the individual doublets that can be considered as making up the actual current distribution of an antenna it is necessary to take into account the phase and the plane of polarization of each contributing component field. Those field strength summations can be done by either graphical or mathematical integration. Many excellent examples of both graphical and mathematical methods appeared in literature printed prior to 1940, for example, F. E. Terman, Radio Engineering, 2d ed, p. 658, McGraw-Hill, New York, 1937. The MININEC moment method of far field radiation calculation is a mathematical integration method based in principle upon the fundamental concept of summing fields from many small elemental sections of thin antenna conductors that compose an antenna system.
Information about the moment method of far radiation field determination has appeared in Amateur Radio literature. For example, Hiroaki Kogure, "Antenna design using PC," CQ Publishing, April 15, 1998, and Matsuda-san JA1WXB "Theory and experience of antenna simulation," Ham Journal No. 95, CQ Publishing. However, those two examples are written in Japanese and are believed to be available only in Japan.
The mathematical calculations required to perform far radiation field integrations are complex and laborious to do manually, but MMANA uses an improved (faster and requiring less memory) MININEC computation engine to do the work for you. You can simply describe an antenna, or load an antenna description file someone else has created, click a Start button, and MMANA will calculate and plot the vertical and horizontal far field radiation patterns of the antenna for you. It also will calculate the feed impedance, feed-line SWR, bandwidth, and other things.
However, the "Garbage In, Garbage Out," rule applies especially well to MMANA and other antenna modeling programs. Fail to describe an antenna properly or ask MMANA to do something that is beyond its capabilities, impossible, or stupid and it will give you either no results or misleading results. MMANA is a very capable and valuable tool if used correctly, but like with most sophisticated tools, correct use requires a certain amount of understanding and care.
- Both table-based and graphical-based editors for antenna design and definition
- A 3-diminsional graphical antenna viewer that shows antenna elements, element current distributions, and the elemental segmentations used when integrating elemental radiation fields
- A far field radiation viewer that shows both horizontal and vertical far field radiation patterns
- A comparator that can be used to compare two or more computation results
- An antenna element editor
- An antenna wire editor
- Tools for defining combinations of pipe or tube elements with stepped diameters
- A user-customizable automatic antenna optimizer capable of optimizing antenna designs with respect to jX, SWR, Gain, F/B, Elevation, and Current
- An antenna optimizer results display table with manual tuning capabilities
- Antenna frequency characteristics plotting
- An antenna specification file generator
- Plus many other things, such as 3-dimensional antenna rotation, antenna stacking, and frequency scaling
Download and Install the free Basic Version of MMANA-GAL
MMANA-GAL Antenna Files Library
Gary, DL2KQ-EU1TT, maintains a Library of MMANA-GAL Antenna Files that all MMANA-GAL users should know about it, because it contains a wealth of antenna designs that can be used as-is or modified to suit individual needs and experimental curiosities.
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