Ubuntu Manpage: create_bmp_for_microstrip_coupler - bitmap generator for microstrip coupler (part of atlc)

NAME

       create_bmp_for_microstrip_coupler - bitmap generator for microstrip coupler (part of atlc)

SYNOPSIS

       create_bmp_for_microstrip_coupler [-b bmp_size] [-v] w s g h t Er1 Er2 filename

WARNING

       This man page is not a complete set of documentation - the complexity of the atlc project makes man pages
       not  an  ideal  way  to  document  it,  although  out  of completeness, man pages are produced.  The best
       documentation that was current at the time the version was produced should be found on your  hard  drive,
       usually at
       /usr/local/share/atlc/docs/html-docs/index.html
       although  it  might  be  elsewhere  if  your system administrator chose to install the package elsewhere.
       Sometimes, errors are corrected in the documentation and placed at http://atlc.sourceforge.net/ before  a
       new  release of atlc is released.  Please, if you notice a problem with the documentation - even spelling
       errors and typos, please let me know.

DESCRIPTION

create_bmp_for_microstrip_coupler is a pre-processor for atlc, part of atlc properties of a two and three
conductor electrical transmission line of arbitrary cross section. The program
create_bmp_for_microstrip_coupler is used as a fast way of generating bitmaps (there is no need to use a
graphics program), for microstrip couplers. Hence if the dimensions of a coupler are known the odd mode,
even mode, differential mode and common mode impedances can be found. If you know what impedances you
require and want to find the dimentions, then use find_optimal_dimensions_for_microstrip_coupler instead.
This makes repeated calls to create_bmp_for_microstrip_coupler. The structure for which bitmaps are
generated by create_bmp_for_microstrip_coupler is shown below.

GGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGG ^
G G |
G G |
G G |
G G |
G G |
G G |
G | G |
G | G |
G | G H
G v <--g--><--w--><---s---><--w--><--g--> G |
GGGGGGGGGG ccccccc ccccccc GGGGGGGG |
GGGGGGGGGG.......ccccccc.........ccccccc.......GGGGGGGG |
G.^.....................................^.............G |
G.|.....................................|.............G |
G.|t.Dielectric, permittivity=Er2.......h.............G |
G.|...(3.7 for FR4 PCB).................|.............G |
G.......................................V.............G |
GGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGG |
GGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGG. v
<------------------------W---------------------------->

The parameters 'W' and 'H' and the inner dimensions of the a metal enclosure. These will generall be
quite large compared to the dimensions of the the PC - the diagram above is not to scale. The gap
between the two coupled lines is s, the width of the coupled lines is w and the spacing between the edges
of the coupled lines and the groundplane on the top is g. Often, the upper groundplane is not close to
the coupled lines, in which case g will be quite large. The thickness of the dielectic is h. Note that he
is just the dielectric, and does not include the thichkness of the copper on the double-sided PCB. The
thickness of copper on the top layer is t. It is immaterial what the thickkness of the lower layer is.
The relative permittivity above the dielectric is normally 1, but the relative permittivity of the
dielectric material will need to be either pre-defined or defined on the command lines. See the section
colours below for more information on dielectrics.

The bitmap is printed to the file specified as the last argument

The bitmaps produced by create_bmp_for_microstrip_coupler are 24-bit bit colour bitmaps, as are required
by atlc.

The permittivities of the bitmap, set by 'Er1' and 'Er2', determine the colours in the bitmap. If Er1 or
Er2 is 1.0, 1.0006, 2.1, 2.2, 2.33, 2.5, 3.3, 3.335, 3.7, 4.8, 10.2 or 100, then the colour corresponding
to that permittivity will be set according to the colours defined in COLOURS below. If Er1 is not one of
those permittivities, the region of permittivity Er1 will be set to the colour 0xCAFF00. If Er2 is not
one of those values, then the region of the image will be set to the colour 0xAC82AC. The program atlc
does not know what these two permittivites are, so they atlc, must be told with the comand line option
-d, as in example 4 below.

OPTIONS

       -C Causes create_bmp_for_microstrip_coupler to print copyright and licensing information.  -b bitmapsize
       is used to set the size of the bitmap, and so the accuracy  to  which  atlc  is  able  to  calculate  the
       transmission line's properties. The default value for 'bitmapsize' is normally 4, although this is set at
       compile time. The value can be set anywhere from 1 to 15, but more than 8 is probably not sensible.

       -v
       Causes  create_bmp_for_microstrip_coupler  to  print  some  data  to  stderr. Note, nothing extra goes to
       standard output, as that is expected to be redirected to a bitmap file.

COLOURS

       The 24-bit bitmaps that atlc expects, have 8 bits assigned to represent the amount of red, 8 for blue and
       8 for green. Hence there are 256 levels of red, green and blue, making a  total  of  256*256*256=16777216
       colours.   Every  one  of the possible 16777216 colours can be defined precisely by the stating the exact
       amount of red, green and blue, as in:

       red         = 255,000,000 or 0xff0000
       green       = 000,255,000 or 0x00ff00
       blue        = 000,000,255 or 0x0000ff
       black       = 000,000,000 or 0x000000
       white       = 255,255,255 or 0xffffff
       Brown       = 255,000,255 or 0xff00ff
       gray        = 142,142,142 or 0x8e8e8e

       Some colours, such as pink, turquoise, sandy, brown, gray etc  may  mean  slightly  different  things  to
       different  people.  This  is  not  so  with  atlc, as the program expects the colours below to be EXACTLY
       defined as given. Whether you feel the colour is sandy or yellow is up to you, but if you use it in  your
       bitmap, then it either needs to be a colour recognised by atlc, or you must define it with a command line
       option (see OPTIONS and example 5 below).
       red    = 255,000,000 or 0xFF0000 is the live conductor.
       green  = 000,255,000 or 0x00FF00 is the grounded conductor.
       blue   = 000,000,000 or 0x0000FF is the negative conductor

       All  bitmaps must have the live (red) and grounded (green) conductor. The blue conductor is not currently
       supported, but it will be used to indicate a negative conductor, which will be needed if/when the program
       gets extended to analyse directional couplers.

       The following dielectrics are recognised by atlc and so are produced by create_bmp_for_rect_cen_in_rect.

       white     255,255,255 or 0xFFFFFF as Er=1.0    (vacuum)
       pink      255,202,202 or 0xFFCACA as Er=1.0006 (air)
       L. blue   130,052,255 or 0x8235EF as Er=2.1    (PTFE)
       Mid gray  142,242,142 or 0x8E8E8E as Er=2.2    (duroid 5880)
       mauve     255.000,255 or 0xFF00FF as Er=2.33  (polyethylene)
       yellow    255,255,000 or 0xFFFF00 as Er=2.5    (polystyrene)
       sandy     239,203,027 or 0xEFCC1A as Er=3.3    (PVC)
       brown     188,127,096 or 0xBC7F60 as Er=3.335  (epoxy resin)
       Turquoise 026,239,179 or 0x1AEFB3 as Er=4.8    (glass PCB)
       Dark gray 142,142,142 or 0x696969 as Er=6.15   (duroid 6006)
       L. gray   240,240,240 or 0xDCDCDC as Er=10.2  (duroid 6010)
       D. orange 213,160,067 or 0xD5A04D as Er=100.0 (mainly for test purposes)

EXAMPLES

       Here  are  a  few  examples  of  the  use  of  create_bmp_for_microstrip_coupler.  Again,  see  the  html
       documentation in atlc-X.Y.Z/docs/html-docs/index.html for more examples.

       In  the  first example, there is just an air dielectric, so Er1=Er2=1.0.  The inner of 1x1 inches (or mm,
       miles etc) is placed centrally in an outer with dimensions 3 x 3 inches.

       The exact place where the dielectric starts (a) and its width (d) are unimportant, but they must still be
       entered.

       % create_bmp_for_microstrip_coupler 3 3 1 1 1 1 1 1 > ex1.bmp
       % atlc ex1.bmp

       In this second example, an inner of 15.0 mm x 0.5 mm is surrounded by an outer with  internal  dimensions
       of  61.5 x 20.1 mm. There is a material with permittivity 2.1 (Er of PTFE) below the inner conductor. The
       output from create_bmp_for_microstrip_coupler is sent to a file ex1.bmp, which is then processed by atlc

       % create_bmp_for_microstrip_coupler 61.5 20.1 5 22 0.5 50 15 5 1.0 2.1 > ex2.bmp
       % atlc ex2.bmp

       In example 3, the bitmap is made larger, to increase accuracy, but otherwise this  is  identical  to  the
       second example.  % create_bmp_for_microstrip_coupler -b7 61.5 20.1 5 22 0.5 50 15 5 1.0 2.1 > ex3.bmp
       % atlc ex3.bmp

       In  the  fourth example, materials with permittivites 2.78 and 7.89 are used. While there is no change in
       how to use create_bmp_for_microstrip_coupler, since these permittivities are not known, we must tell atlc
       what they are.  % create_bmp_for_microstrip_coupler 61 20 1 4 22 0.5 50 15 5 2.78 7.89 > ex5.bmp  %  atlc
       -d CAFF00=2.78 -d AC82AC=7.89 ex5.bmp In the sixth and final example, the -v option is used to print some
       extra data to stderr from create_bmp_for_microstrip_coupler.