Examples of Structure Geometry Data
Rhombic Antenna - No Symmetry
Structure: Figure 7
Geometry Data Cards
```GW 1  10  350.        0.  150.   0.  150.  150.  .1

GW 2  10    0.      150.  150. 350.    0.  150.  .1

GW 3  10 -350.        0.  150.   0.  150.  150.  .1

GW 4  10    0.     -150.  150. 350.    0.  150.  .1

GS          0.30480

GE

```
Number of Segments: 40
Symmetry: None
These cards generate segment data for a rhombic antenna. The data are input in dimension of feet and scalled to meters. In the figure, numbers near the structure represent segment numbers and circuled numbers represent tag numbers
Rhombic Antenna - Plane Symmetry, 2 Planes
Structure: Figure 8
Geometry Data Cards
```GW 1  10 -350.        0.  150.   0.  150.  150.  .1

GX 1  110

GS          0.30480

GE

```
Number of Segments: 40
Symmetry: Two planes
These cards generate the same structure as the previous set allthough the segment numbering is altered. By making use of two planes of symmetry, these data will require storage of only a 10 by 40 interaction matrix. If segments 21 and 31 are to be loaded as the termination of the antenna, then symmetry about the YZ plane cannot be used. The following cards will result in symmetry about only the xZ plane being used in the solution; thus, allowing segments on one end of the antenna to be loaded.
Rhombic Antenna - Plane Symmetry, 1 Plane
Structure: Figure 9
Geometry Data Cards
```GW 1  10 -350.        0.  150.   0.  150.  150.  .1

GX 1 100

GX 2 010

GS          0.30480

GE

```
Number of Segments: 40
Symmetry: One plane
Segments 1 through 20 of this structure are in the first symmetric section. Hence, segments 11 and 31 can be loaded without loading segments 1 and 21 (loading segments in symmetric structures is discussed in the section covering the LD card). These data will cause storage of a 20 by 40 interaction matrix.
Two Coaxial Rings
Structure: Figure 10
Geometry Data Cards
```GW 1   1    1.0       0.       0.     0.70711  0.70711  0.      .001

GW 2   1    2.0       0.       0.     0.76536  1.84776  0.      .001

GW 2   1    0.76536   1.84776  0.     1.41421  1.41421  0.      .001

GR     8

GM         90.0       0.       0.     0.       0.       2.0

GE

```
Number of Segments: 24
Symmetry: 8 section cylindrical symmetry
The first 45 degree section of the two rings is generated by the first three GW cards. This section is then rotated about the X-axis to complete the structure. The rings are then rotated about the X-axis and elevated to produce the structure shown. Since no tag increment is specified on the GR card. All segments on the first ring have tags of 1 and all segments on the second ring have tags of 2. Because of symmetry, these data will require storage of only a 3 by 24 interaction matrix. IF a 1 were punched in column 5 of the GE card, however, wymmetry would be destroyed by the interaction with the ground, requiring stroage of a 24 by 24 matrix
Linear Antenna over a Wire Grid Plate
Structure: Figure 11
Geometry Data Cards
```GW     1    0.        0.       0.     0.1   0.   0.      .001

GW     1    0.        0.       0.     0.    0.1  0.      .001

GM     2    0.        0.       0.     0.    0.1  0.

GW     1    0.        0.3      0.0    0.1   0.3  0.      .001

GM     4    0.        0.       0.     0.1   0.   0.

GW     3    0.5       0.       0.     0.5   0.3  0.      .001

GM          0.        0.       0.    -0.25 -0.15 0.

GW 1   5   -0.25      0.       0.15   0.25  0.   0.15    .001

GE

```
Number of Segments: 43
Symmetry: None
The first 6 cards generate data for the wire grid plate, with the lower left-handcorner at the coordinate origin, by using the GM card to reproduce sections of the structure. The GM card is then used to move the center of the plate to the origin. Finally, a wire is generated 0.15 meters above the plate with a tag of 1.
Cylinder with Attached Wwires
Structure: Figure 12
Geometry Data Cards
```SP         10.        0.       7.3333   0.    0.    38.4

SP         10.        0.       0.       0.    0.    38.4

SP         10.        0.       7.3333   0.    0.    38.4

GM     1    0.        0.      30.

SP          6.89      0.      11.      90.    0.    44.89

SP          6.89      0.      11.      90.    0.    44.89

GR     6

SP          0.        0.      11.      90.    0.    44.89

SP          0.        0.      11.      90.    0.    44.89

GW     4    0.        0.      11.       0.    0.    23.       .1

GW     5   10.        0.       0.      27.6   0.     0.       .2

GS           .01

GE

```
Number of Segments: 9
Number of Patches: 56
Symmetry: None
The cylinder is generated by first specifing three patches in a column centered on the X asis as shown in figure 12(a). A GM card is then used to produce a second column of patches rotated about the Z axis by 30 eegrees. A patch is added to the top and another to the bottom to form parts of the end surfaces. The model at this point is shown in figure 12(b). next a GR card is used to rotate this section of patches about the Z axis to form a total of six similar sections, including the original. A patch is then added to the center of the top and another to the bottom to from the complete cylinder shown in figure 12(c). Finally, two GW cards are used to add wires connecting to the top and side of the cylinder. The patches to which the wires are connected are devided into four smaller patches as shown in figure 12(d). Although patch shape is not input to the program, square patches are assumed at the base of a connected wire when integrated over the surface current. Hence, a more accurate representation of the model would be as shown in figure 13, where the patches to which wires connect are square with equal areas maintained for all patches (before subdivision).