circ_in_rect(1)             General Commands Manual            circ_in_rect(1)

       circ_in_rect - bitmap generator for a circular conductor inside a
       rectangular conductor (part of atlc)

       circ_in_rect [options... ] d W H x y Er

       This man page is not a complete set of documentation. See the html
       files for more complete information. So far, I've not managed to
       install the html files into /usr/local, so you will have to look into
       the atlc-X.Y.Z/docs/html-docs directory for them.

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

       --------------------------------------------------------  ^
       |                                                      |  |
       |                                                      |  |
       |                                                      |  |
       |                                                      |  |
       |                                                      |  |
       |           Dielectric, permittivity=Er                |  |
       |                                                      |  |
       |                                                      |  |
       |                                                      |  |
       |                                                      |  |
       |         <------x------> ^                            |  H
       |       *****             |                            |  |
       |    ***********          y                            |  |
       |   *************         |                            |  |
       |   **************        |                            |  |
       |   <-----d------>        v                            |  |
       |   **************                                     |  |
       |   *************                                      |  |
       |    ***********                                       |  |
       |        ***                                           |  |
       |                                                      |  |
       -------------------------------------------------------   v

       The parameters 'W' and 'H' and the inner dimensions of the outer
       conductor.  The inner conductor has a diameter of 'd' and is offset
       from the centre of the outer conductor by an amount 'x' horizontally
       and 'y' vertically.  The space between the inner and outer conductors
       is a dielectric of relative permittivity 'Er'. If there is just a
       vacuum dielectric, then 'Er' should be set to 1.0

       The bitmap is printed to standard output, which MUST be re-directed to
       either a file in one of the following two ways.

       circ_in_rect  d W H x y Er > filename.bmp OR
       circ_in_rect -f filename.bmp d W H x y Er

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

       The permittivities of the bitmap, set by 'Er', determine the colours in
       the bitmap. If Er1 is 1.0, 1.006, 2.1, 2.2, 2.33, 2.5, 3.3, 3.335, 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 programme atlc does not know what these
       permittivites are, so atlc, must be told with the -d command line
       option, 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 circ_in_rect 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

       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, turquiose, sandy, brown, gray etc may mean
       slightly different things to different people. This is not so with
       atlc, as the programme 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).
       The following conductors are recognised by atlc:
       red    = 255,000,000 or 0xff0000 is the live conductor.
       green  = 000,255,000 or 0x00ff00 is the grounded conductor.
       black  = 000,000,000 or 0x000000 is the negative conductor

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

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

       white     255,255,255 or 0xFFFFFF as Er=1.0   (vacuum)
       white     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)
       Terquoise 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)
       D. Orange 213,160,077 or 0xD5A04D as Er=100   (for testing)
       If the permittivity is one not in the above list, then those parts of
       the image with Er1 will be set to 0xCAFF00, and those parts with Er2 to

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

       % circ_in_rect 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 circ_in_rect is sent to a file ex1.bmp, which is then
       processed by atlc

       % circ_in_rect 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.  % circ_in_rect -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, instead of re-directing circ_in_rect's output to
       a file with the > sign, it is done using the -f option.
       % circ_in_rect -f ex4.bmp 61.5 20.1 5 22 0.5 50 15 5 1.0 2.1
       % atlc ex4.bmp

       In the fifth example, materials with permittivites 2.78 and 7.89 are
       used. While there is no change in how to use circ_in_rect, since these
       permittivities are not known, we must tell atlc what they are.  %
       circ_in_rect 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 circ_in_rect.

       atlc(1), rect_cen_in_rect(1), circ_in_circ(1). rect_in_circ(1),
       rect_in_rect(1).  rect_in_circ(1), readbin(1) and sym_strip(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              - my home page          - ham radio pages

Dr. David Kirkby              atlc-3.0.1 29/3/02               circ_in_rect(1)