Discone

Hello everybody,

        I am faced with a problem regarding the modeling of a wideband discone.
The radiation pattern obtained seems to be quite the same as that of the specs,
however, the VSWR is really different. The problem seems to be the fact that
the imaginary part of the impedance is far too large thus affecting the
results. When the imaginary part was divided by a large number to decrease it's
effect, the result proved to be better. I was wondering if anyone could help
me.

        Thank you in advance.

Below is the code of the NEC input file.

CM, THIS IS THE TOWER THAT HOLDS THE ANTENNA
CM, SIMILATION IS DONE AT 290.4MHz
CM, THA ANTENNA TAG NUMBER STARTS WITH 5000
CM, EXCITED AT THE JUNCTION WHERE ALL POINTS MEET
CE
GW 1 10 0.000 0.000 1.00 0.000 0.000 0.00 0.01
GW 2 7 0.000 0.000 1.00 -0.370 0.153 0.50 0.01
GW 3 7 0.000 0.000 1.00 -0.153 0.370 0.50 0.01
GW 4 7 0.000 0.000 1.00 0.153 0.370 0.50 0.01
GW 5 7 0.000 0.000 1.00 0.370 0.153 0.50 0.01
GW 6 7 0.000 0.000 1.00 0.370 -0.153 0.50 0.01
GW 7 7 0.000 0.000 1.00 0.153 -0.370 0.50 0.01
GW 8 7 0.000 0.000 1.00 -0.153 -0.370 0.50 0.01
GW 9 7 0.000 0.000 1.00 -0.370 -0.153 0.50 0.01
GW 5000 5 0.000 0.000 1.05 -0.196 0.081 1.05 0.01
GW 5001 5 0.000 0.000 1.05 -0.081 0.196 1.05 0.01
GW 5002 5 0.000 0.000 1.05 0.081 0.196 1.05 0.01
GW 5003 5 0.000 0.000 1.05 0.196 0.081 1.05 0.01
GW 5004 5 0.000 0.000 1.05 0.196 -0.081 1.05 0.01
GW 5005 5 0.000 0.000 1.05 0.081 -0.196 1.05 0.01
GW 5006 5 0.000 0.000 1.05 -0.081 -0.196 1.05 0.01
GW 5007 5 0.000 0.000 1.05 -0.196 -0.081 1.05 0.01
GE 0
FR,0,16,0,0,180,20,0,0
EX,0,5000,1,00,1,0
EX,0,5001,1,00,1,0
EX,0,5002,1,00,1,0
EX,0,5003,1,00,1,0
EX,0,5004,1,00,1,0
EX,0,5005,1,00,1,0
EX,0,5006,1,00,1,0
EX,0,5007,1,00,1,0
XQ
EN

                                   
Yee Hui .
Received on Fri Jan 26 1996 - 06:11:00 EST