NEC-LIST: Is there any way to use 'WX' card when modeling the lpda?

hi,friends,
I am writing to ask for help about the way of using 'WX' card when
 modeling the log-periodic antennas. The lpda is symmetrical about
 the plane perpendicular to the antenna plane. When modeling by nec2,
 we have to set a single one segment to including the feeline by 'TL'
 cards, destroying the symmetry.

    An alternative is to use Numerical Green' Function (NGF), but it
 cannot support computation at multiple frequencies. It brings much
inconvenience. how can i improve this?
 
Here is another question about the antennas' pattern:
 
  The horizontal LPDA on the grond radiates towards a high elevation
 during the shortwave band, when the antenna is not high enough. eg.,
 60 degree. If the dipole of the lpda is y-directed ,when we need to plot its pattern in the vertical and horizontal plane, we fix the
azimuth to be 0 degree and 180 degree to get the pattern in vertical
plane, and fix the elevation 60 degree(in accordance with theta 30
degree) to get the pattern in horizontal plane. The problem is that
the 3dB beamwidth of the horizontal pattern is probably larger the
120 degree, or even more. I use the shortcut 'M' to display multi-
pattern in the 4nec2 , i.e., independent vertical, horizontal and
total gain pattern, when I find the pattern of the horizontal gain is
not so wide, the key is the beam of vertical gain. In y-direction,
the horizontal gain is assumed to be none and the vertical gain is
arriving at its maximum. Then I check the way of computing the
antenna's pattern. The y-directed dipole currents radiate two
orthogonal electric field: E-theta and E-phi, the magnitude is cos
(theta)*sin(phi) and cos(phi) respectively. When phi=90 degree, E-
phi=0 and E-theta=cos(theta), if theta is small, we get large E-
theta, which is regarded as the vertical component, widening the
pattern in the side-direction. I wonder if I can use the horizontal
gain as the antenna's pattern in horizontal plane instead of the
total gain. How can I explain this? If I cannot do like that ,the
lpda's pattern in horizontal is too wide, is there something i can
do to improve this?

     Thank you all ,too long questions and maybe too simple.
          sincerely
                 Xiaolin Zhang
                 28/09/90

"VP9zVFTl",1/22JvVP9z60DjMyJB

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