Provided by: atlc_4.6.1-5_amd64 bug


       create_bmp_for_circ_in_circ  -  bitmap  generator  for  circular conductor inside circular
       conductor (part of atlc)


       create_bmp_for_circ_in_circ [options... ] D d O Er filename.bmp


       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
       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  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


       create_bmp_for_circ_in_circ  is  a  pre-processor  for atlc, the finite difference program
       that is used to  calculate  the  properties  of  a  two  and  three  conductor  electrical
       transmission  line  of arbitrary cross section. The program create_bmp_for_circ_in_circ is
       used as a fast way of generating bitmaps (there is no need to use a graphics program), for
       a circular conductor inside a circular conductor (coaxial conductors), like this:

                       ****                 ****
                    ****    <-----d------>     ****
                  ***            *****            ***
                ***           ***********           ***
              ***            *************            ***
             ***            ***************            ***
            ***      ^      ***************             ***
           ***       |      ***************              ***
          ***        |       *************                ***
          **         O        ***********                  **
         ***         |            ***                      ***
         **          |                                      **
         **                                                 **
         **                                                 **
         **                                                 **
         ***                                               ***
          **                                               **
          ***                                             ***
           **                                             **
            **                                           **
             **                                         **
              ***                                     ***
               ****                                 ****
                 ****                             ****
                   *****                       *****
                      ******               ******

       The  parameter  'D'  is  the  inner dimensions of the outer conductor and 'd' is the outer
       diameter of the inner conductor.  The inner conductor is offset 'h' from the centre of the
       outer  conductor.  The whole region is surrounded by a dielectric of relative permittivity

       The bitmap is printed to 'outfile.bmp' - the last command line argument.

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

       The  permittivities  of the dielectric 'Er' determines the colours in the bitmap. If Er is
       1.0, 1.006, 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 Er is not one of those permittivities, the region of permittivity Er will be set
       to the colour 0xCAFF00. The program atlc does not know what this permittivity is, so atlc,
       must be told with the command line option -d, as in example 4 below.


       -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.

       -f outfile
       Set  the  output filename. By default, the bitmap is sent to stdout, but it *must* be sent
       to a file, with this option, or as described above.

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


       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 reconised by
       atlc, or you must define it with a command line option (see OPTIONS and example 5 below).
       The following conductors are reconised by atlc:
       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 0x000000 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   reconised   by   atlc   and   so   are   produced   by

       white     255,255,255 or 0xFFFFFF as Er=1.0   (vacuum)
       pink      255,202,202 or 0xFFCACA as Er=1.0006 (air)
       blue      000,000,255 or 0x0000FF 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 ox696969 as Er=6.15  (duroid 6006)
       L. gray   240,240,240 or 0xDCDCDC as Er=10.2  (duroid 6010)


       Although  create_bmp_for_circ_in_circ is used for circular inner and outer conductors, the
       outside of the outer conductor is drawn as a square. This is for convenience and makes  no
       difference to the calculations. The inside is of the outer conductor is drawn as a circle.


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

       1) In the first example, the outer conductor has an inside diameter of 12  units  (inches,
       mm,  feet  etc.),  the  inner  has  an outside diameter of 3.9 units.  The inner is placed
       centrally (h=0) and the dielectric is vacuum (Er=1.0).
       % create_bmp_for_circ_in_circ 12 3.9 0 1.0 coaxial_1.bmp
       % atlc coaxial_1.bmp
       atlc will indicate the correct value of impedance to be 67.3667  Ohms,  whereas  an  exact
       analysis will show the true value to be 67.4358 Ohms, so atlc has an error of 0.102%.

       2)  In  this  second  example,  the conductor sizes are the sames as in example 1, but the
       inner is located 3.5 units off-centre and the dielectric has a  relative  permittivity  of
       2.1 (Er of PTFE) The output is sent to a file not_in_centre.bmp which is then processed by
       % create_bmp_for_circ_in_circ 12 3.9 3.5 2.1 not_in_centre.bmp
       % atlc not_in_centre.bmp
       The impedance of this is theoretically 24.315342 Ohms, as create_bmp_for_circ_in_circ will
       calculate for you. atlc's estimate is 24.2493 Ohms, an error of only -0.271 %.

       3)  In  the  third  example the bitmap is made larger, to increase accuracy, but otherwise
       this is identical to the previous one.
       % create_bmp_for_circ_in_circ -b8 12 3.9 3.5 2.1 bigger_not_in_centre.bmp
       % atlc bigger_not_in_centre.bmp
       This time atlc will take much longer to calculate Zo, since the bitmap is larger and so it
       needs  to do more calculations. However, the final result should be more accurate. In this
       case, the result reported is 24.2461 Ohms, an error that's marginally smaller than  before
       at  0.285  %.  It is possible there may be something to be gained by decreasing the cutoff
       at larger grids, so this is being investigated. However, errors almost always  below  0.25
       %, no matter what is being analysed.

       In the fourth example, a material with a relativity permittivity 7.89 of is used. There is
       no change in how to use create_bmp_for_circ_in_circ, but since this  permittivity  is  not
       one  of  the  pre-defined  values (see COLOURS), we must tell atlc what it is.  The colour
       will be set an olive green one, with a hexacidcal representation  of  red=0xCA,  blue=OxFF
       and  green  = 0x00. This just happens to be the default colour  used when the permittivity
       is unknown. So atlc must be given this information, like thisL
       % create_bmp_for_circ_in_circ 23 9 0 7.89 an_odd_er.bmp
       % atlc -d CAFF00=7.89 an_odd_er.bmp This has a theoretical impedance  of  20.041970  Ohms,
       but  atlc  version  3.0.1 will calculate it to be 20.0300, an error of -0.058 % !!! If you
       look at the file an_odd_er.bmp with a graphics package, you will see there are  3  colours
       in it - the red inner conductor, the green outer and an olive-green dielectric.


       design_coupler(1) find_optimal_dimensions_for_microstrip_coupler(1) readbin(1)                - Home page       - Download area
       atlc-X.Y.Z/docs/html-docs/index.html       - HTML docs
       atlc-X.Y.Z/docs/qex-december-1996/atlc.pdf - theory paper
       atlc-X.Y.Z/examples                        - examples