|Zo= 49.335 Ohms
C= 67.611 pF/m
L= 164.565 nH/m
|Zo= 56.020 Ohms
C= 59.544 pF/m
L= 186.862 nH/m
|Zo= 66.3699 Ohms
Zodd= 31.6915 Ohms
atlcneeds to know shape of the transmission line's cross section. This cross section is stored in a data file, which happens to be a Windows bitmap file. The bitmap file is read by
atlc, following which the programme performs the analysis.
rect_in_rect, which is able to automatically generate a bitmap for any rectangular conductor, inside any other rectangular conductor, with no more than 2 dielectrics. One dielectric must lie under the centre conductor. Other programs include
atlc. The programme should compile very easily and quickly. Being rather CPU intensive,
atlchas been written to support multiple processors if available. Here is an example of using atlc, with the file
ushape.bmpbeing drawn by a graphics programme.
% atlc -v ushape.bmp ushape.bmp Er= 1.000000 C= 77.2797 pF/m L= 143.977094 nH/m Zo= 43.163247 Ohms v= 299792458.010503 m/s v_f= 1.000000 VERSION= 3.0.0 ushape.bmp Er= 1.000000 C= 77.1386 pF/m L= 144.240432 nH/m Zo= 43.242194 Ohms v= 299792458.010503 m/s v_f= 1.000000 VERSION= 3.0.0 ushape.bmp Er= 1.000000 C= 77.1385 pF/m L= 144.240554 nH/m Zo= 43.242230 Ohms v= 299792458.010503 m/s v_f= 1.000000 VERSION= 3.0.0 ushape.bmp Er= 1.000000 C= 77.1385 pF/m L= 144.240554 nH/m Zo= 43.242230 Ohms v= 299792458.010503 m/s v_f= 1.000000 VERSION= 3.0.0It will be seen that
atlcmakes several estimates of the transmission line's properties, each subsequent one being closer to the true values (normally only the final result is shown, but the -v option added above causes
atlcto print intermediate results).
rect_in_rectto generate a bitmap The programme needs 11 parameters on its command line, which are described fully elsewhere. For now, just accept that these 11 parameters describe a transmission line. The output of
rect_in_rectis redirected to the file
ex2.bmp, which is then read by
% rect_in_rect 250 175 10 32 4 200 56 25 1.0 2.5 > ex2.bmp % atlc ex2.bmp ex2.bmp Er= MIXED C= 87.8016 pF/m L= 240.9628 nH/m Zo= 52.387023 Ohms v= 217407041.146 m/s v_f= 0.725192 VERSION=3.0.0
atlcwas written by, and is supported by, Dr. David Kirkby (G8WRB).
atlc is written and supported by Dr. David Kirkby (G8WRB)It is issued under the GNU public license.