1 .TH atlc 1 "atlc-4.4.2 10th Sept 2003" "Dr. David Kirkby"
4 \fBatlc\fR - an Arbitrary Transmission Line Calculator
6 \fBatlc [-C] [-s] [-S] [-v] [-c cutoff] [-d rrggbb=Er] [-i factor] [-i prefix] [-t threads] [-r rate_multiplier] bitmapfile\fR
9 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.
10 The best documentation that was current at the time the version was produced should be found on your
11 hard drive, usually at
13 /usr/local/share/atlc/docs/html\-docs/index.html
15 although it might be elsewhere if
16 your system administrator chose to install the package elsewhere. Sometimes, errors are corrected
17 in the documentation and placed at http://atlc.sourceforge.net/ before a new release of atlc is
18 released. Please, if you notice a problem with the documentation - even spelling errors and typos,
22 \fBatlc\fR is a finite difference program that is used to calculate the
23 properties of a two-conductor electrical transmission line of arbitrary
24 cross section. It is used whenever there are no analytical formula known,
25 yet you still require an answer. It can calculate:
27 The impedance Zo (in Ohms)
29 The capacitance per unit length (pF/m)
31 The inductance per unit length (nF/m)
33 The velocity of propagation v (m/s)
35 The velocity factor, v/c, which is dimensionless.
37 A bitmap file (usually with the extension .bmp or .BMP) is drawn in a graphics
38 package such as \fBGimp\fR available from http://www.gimp.org. The bitmap
39 file \fBmust\fR be saved as a 24-bit (16,777,216 colour) uncompqessed file. The
40 colours used in the bitmap indicate whether the region is a conductor (pure
41 red, pure green or pure blue) or a dielectric (anything else). Pure white
42 is assumed to be a vacuum dielectric, but other colours have different meanings.
43 See COLOURS below for precise definitions of the colours.
47 print copyright, licensing and copying information.
51 Skip writing the Ex, Ey, E, V, U and Er bitmap (.bmp) files
54 Skip writing the Ex, Ey, E, V, U and Er binary (.bin) files
58 makes the output more verbose/talkative.
62 Sets the convergence criteria of the finite difference program. The
63 default is 0.0001, meaning two separate iterations must be within
64 01% for the program to stop iterating. Setting to a smaller positive
65 number gives more accuracy, but takes longer.
69 is used to indicate the colour 0xrrggbb in the bitmap is used to
70 represent a material with permittivity Er. See also COLOURS below
74 is used to lighten or darken the .bmp electric field profile images
75 produced by atlc. Set factor > 2 to lighten or between 1 and 2 to
78 \fB-r ratemultiplier\fR
80 Sets the parameter 'r' used internally when computing the voltage at a point w,h.
81 The default, which is (as of version 3.0.0) 1.95, results in what is believed to be
82 optimal results. Setting to 1.0 will avoid the use of the fast convergence method,
83 which is generally not a good idea.
87 Adds 'prefix', which is usually a directory name, in front of the output files.
95 The 24-bitmaps that atlc uses have 8 bits assigned
96 to represent the amount of red, 8 for blue and 8 for green. Hence there are
97 256 levels of red, green and blue, making a total of 256*256*256=16777216 colours.
98 Every one of the possible 16777216 colours can be defined precisely by the stating the exact amount
99 of red, green and blue, as in:
102 red = 255,000,000 or 0xff0000
104 green = 000,255,000 or 0x00ff00
106 blue = 000,000,255 or 0x0000ff
108 black = 000,000,000 or 0x000000
110 white = 255,255,255 or 0xffffff
112 Brown = 255,000,255 or 0xff00ff
114 gray = 142,142,142 or 0x8e8e8e
116 Some colours, such as pink, turquiose, sandy, brown, gray etc may mean slightly
117 different things to different people. This is not so with atlc, as the
118 program expects the colours below to be exactly defined as given. Whether
119 you feel the colour is sandy or yellow is up to you, but if you use it in
120 your bitmap, then it either needs to be a colour reconised by atlc, \fBor\fR
121 you \fBmust\fR define it with a command line option (see OPTIONS).
123 red = 255,000,000 or 0xFF0000 is the live conductor.
125 green = 000,255,000 or 0x00FF00 is the grounded conductor.
127 blue = 000,000,255 or 0x0000FF is the negative conductor
129 All bitmaps \fBmust\fR have the live (red) and grounded (green) conductor. The blue
130 conductor is used to indicate a negative conductor, is needed when the program
131 is used to analyse directional couplers.
133 The following dielectrics are reconised by \fRatlc\fB:
136 white 255,255,255 or 0xFFFFFF as Er=1.0 (vacuum)
138 pink 255,202,202 or 0xFFCACA as Er=1.0006 (air)
140 L. blue 130,052,255 or 0x8235EF as Er=2.1 (PTFE)
142 Mid gray 142,242,142 or 0x8E8E8E as Er=2.2 (duroid 5880)
144 mauve 255.000,255 or 0xFF00FF as Er=2.33 (polyethylene)
146 yellow 255,255,000 or 0xFFFF00 as Er=2.5 (polystyrene)
148 sandy 239,203,027 or 0xEFCC1A as Er=3.3 (PVC)
150 brown 188,127,096 or 0xBC7F60 as Er=3.335 (epoxy resin)
152 L. yellow 223,247,136 or 0xDFF788 as Er=3.7 (FR4 PCB)
154 Turquoise 026,239,179 or 0x1AEFB3 as Er=4.8 (glass PCB)
156 Dark gray 142,142,142 or 0x696969 as Er=6.15 (duroid 6006)
158 L. gray 240,240,240 or 0xDCDCDC as Er=10.2 (duroid 6010)
160 D. orange 213,160,067 or 0xD5A04D as Er=100.0 (mainly for test purposes)
164 Here are a few examples of the use of atlc. Again, see the html documentation in atlc-X.Y.Z\docs\html-docs,
165 the documentation on your system (normally at /usr/local/share/atlc/docs/html\-docs/index.html ) or online
166 at http://atlc.sourceforge.net for examples.
168 \fBex_1 % atlc coax2.bmp\fR
170 This is a simple example (ex_1), in which the geometry of a transmission line is defined in coax2.bmp. In
171 this example, only the predefined dielectrics (Er =1.0, 1.0006, 2.1, 2.2, 2.33, 2.5, 3.3, 3.335, 3.7,
173 or 10.2) could have been used in the bitmap, which would have been done with one of 13 different colours. white (0xFFFFFF) for Er=1.0, pink (0xFFCACA) for 1.0006 etc.
174 No other colour (dielectric) could have been used, since it was not
175 specified with the -d option.
178 \fBex_2 % atlc -d f9e77d=2.43 somefile.bmp \fR
180 In ex_2, a dielectric with Er=2.43 was wanted. A colour with the RGB values of 0xF9E7&d was
181 used. The -d option tells atlc what Er this colour refers to.
184 \fBex_3 % atlc -v coax2.bmp\fR
186 In ex_3, atlc has been instructed to print the results of intermediate calculations to stdout.
187 Normally, only the final result is printed. Using -vv even more information may be produced, but this
188 is really of only use to the developer of the project.
192 Original bitmap file. Must be 24-bit colour uncompressed.
196 X-component of E-field as a bitmap. Red=+dV/dx, blue =-dV/dx
199 y-component of E-field as a bitmap. Red=+y, blue =-y
203 E-field, as E=sqrt(Ex^2+Ey^2).
207 Voltage as a bitmap, red= positive, blue =negative.
211 Bitmap showing the permittivity as a grayscale. Lighter is a higher
219 In addition to the bitmaps, the data is also saved in binary files.
221 All the saved binary files (.bin's) are saved as a double precision
222 number for each of the pixels. The first double is the top left, the
223 last the bottom right. If the original image has width W and height H,
224 the saved binary files will be W-1 by H-1.
226 All the saved bitmap files are 24-bit uncompressed, just like the input
231 create_bmp_for_circ_in_circ(1)
232 create_bmp_for_circ_in_rect(1)
233 create_bmp_for_microstrip_coupler(1)
234 create_bmp_for_rect_cen_in_rect(1)
235 create_bmp_for_rect_cen_in_rect_coupler(1)
236 create_bmp_for_rect_in_circ(1)
237 create_bmp_for_rect_in_rect(1)
238 create_bmp_for_stripline_coupler(1)
239 create_bmp_for_symmetrical_stripline(1)
241 find_optimal_dimensions_for_microstrip_coupler(1)
245 http://atlc.sourceforge.net - Home page
247 http://sourceforge.net/projects/atlc - Download area
249 atlc-X.Y.Z/docs/html-docs/index.html - HTML docs
251 atlc-X.Y.Z/docs/qex-december-1996/atlc.pdf - theory paper
253 atlc-X.Y.Z/examples - examples