NAME
circ_in_rect - bitmap generator for a circular conductor
inside a rectangular conductor (part of atlc)
SYNOPSIS
circ_in_rect [options... ] d W H x y Er
WARNING
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.
DESCRIPTION
circ_in_rect is a pre-processor for atlc, the finite differ-
ence 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 graph-
ics programme), for a circular conductor inside a rectangu-
lar conductor, like this:
-------------------------------------------------------- ^
| | |
| | |
| | |
| | |
| | |
| Dielectric, permittivity=Er | |
| | |
| | |
| | |
| | |
| <------x------> ^ | H
| ***** | | |
| *********** y | |
| ************* | | |
| ************** | | |
| <-----d------> v | |
| ************** | |
| ************* | |
| *********** | |
| *** | |
| | |
------------------------------------------------------- v
<---------------------------W-------------------------->
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.
OPTIONS
-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.
-v
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.
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 pos-
sible 16777216 colours can be defined precisely by the stat-
ing 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, 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 circ_in_rect.
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 0xAC82AC.
EXAMPLES
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 sur-
rounded 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 accu-
racy, 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.
SEE ALSO
atlc(1), rect_cen_in_rect(1), circ_in_circ(1).
rect_in_circ(1), rect_in_rect(1). rect_in_circ(1), read-
bin(1) and sym_strip(1).
http://atlc.sourceforge.net - Home page
http://sourceforge.net/projects/atlc - 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
http://www.david-kirkby.co.uk - my home page
http://www.david-kirkby.co.uk/ham - ham radio pages
Man(1) output converted with man2html