Analysis of Crossed Dipole in Circular Cavity
The results of a crossed-dipole mounted in a cup Modern Antenna Design, 2ed, Wiley/IEEE Press, p. 246-247 have been extended over a range of dimensions. These designs are suitable as feeds for a reflector or useful in themselves. A full report showing their patterns and frequency responses is available as a download: cup_dipoles.
Summary of Results
Aperture |
Base |
Depth |
Gain |
Beam- |
Opt. |
Illum. |
Phase |
Band- |
10 dB |
0.6 |
0.6 |
0.3 |
6.4 |
85.6 |
0.32 |
1.70 |
0.332 |
22% |
182.5 |
0.6 |
0.6 |
0.5 |
7.2 |
82.1 |
0.36 |
1.94 |
0.503 |
15.% |
171.3 |
0.7 |
0.7 |
0.3 |
7.4 |
79.0 |
0.36 |
1.66 |
0.334 |
28% |
162 |
0.7 |
0.7 |
0.5 |
8.0 |
73.4 |
0.40 |
1.73 |
0.486 |
20% |
147.3 |
0.8 |
0.8 |
0.5 |
8.7 |
68.6 |
0.44 |
1.57 |
0.478 |
37% |
133 |
0.88 |
0.57 |
0.44 |
9.1 |
65.2 |
0.48 |
1.48 |
0.415 |
21% |
123.3 |
0.9 |
0.9 |
0.3 |
9.0 |
65.6 |
0.44 |
1.44 |
0.303 |
27% |
128.4 |
0.9 |
0.9 |
0.4 |
9.2 |
63.9 |
0.44 |
1.49 |
0.393 |
28% |
123.6 |
0.9 |
0.9 |
0.5 |
9.3 |
63.5 |
0.48 |
1.48 |
0.474 |
32% |
121.6 |
0.9 |
0.9 |
0.6 |
9.3 |
64.7 |
0.48 |
1.47 |
0.566 |
44% |
120.6 |
1.0 |
1.0 |
0.3 |
9.7 |
61.1 |
0.48 |
1.43 |
0.291 |
23% |
118.0 |
1.0 |
1.0 |
0.3 |
9.6 |
61.5 |
0.48 |
1.44 |
0.287 |
27% |
119.0 |
1.0 |
1.0 |
0.4 |
9.8 |
59.9 |
0.52 |
1.51 |
0.393 |
26% |
115.1 |
1.0 |
1.0 |
0.5 |
10.0 |
58.7 |
0.48 |
1.44 |
0.480 |
29% |
111.3 |
1.0 |
1.0 |
0.6 |
10.0 |
59.2 |
0.56 |
1.59 |
0.580 |
28% |
111.0 |
1.0 |
0.65 |
0.5 |
9.8 |
61.1 |
0.48 |
1.43 |
0.455 |
25% |
114.8 |
1.1 |
1.1 |
0.4 |
10.5 |
55.4 |
0.56 |
1.94 |
0.289 |
20% |
105.5 |
1.1 |
1.1 |
0.5 |
10.7 |
54.1 |
0.56 |
1.47 |
0.491 |
20% |
101.9 |
1.1 |
1.1 |
0.6 |
10.8 |
54.1 |
0.60 |
1.76 |
0.583 |
28% |
100.8 |
1.2 |
0.65 |
0.5 |
10.7 |
54.2 |
0.52 |
1.36 |
0.395 |
33% |
102.9 |
1.3 |
0.65 |
0.5 |
11.2 |
51.0 |
0.56 |
1.37 |
0.364 |
28.5% |
97.3 |
1.4 |
0.65 |
0.5 |
11.5 |
49.1 |
0.60 |
1.58 |
0.249 |
29% |
95.4 |
1.5 |
0.65 |
0.5 |
11.7 |
47.7 |
0.56 |
1.60 |
0.208 |
24% |
94.3 |
1.6 |
0.65 |
0.44 |
11.3 |
47.9 |
0.56 |
1.52 |
0.132 |
23% |
96.4 |
1.7 |
0.65 |
0.44 |
11.1 |
47.3 |
0.52 |
1.54 |
0.102 |
26.5% |
96.9 |
1.7 |
0.80 |
0.44 |
11.6 |
45.2 |
0.60 |
1.61 |
0.050 |
26% |
90.7 |
1.7 |
0.90 |
0.44 |
12.1 |
43.3 |
0.68 |
1.65 |
0.037 |
24.5% |
85.7 |
1.7 |
1.0 |
0.44 |
12.5 |
41.4 |
0.68 |
1.79 |
-0.035 |
22.5% |
81.8 |
1.7 |
1.1 |
0.44 |
12.6 |
39.4 |
0.64 |
2.10 |
-0.164 |
21% |
83.6 |
1.8 |
1.0 |
0.44 |
12.6 |
39.7 |
0.56 |
2.02 |
-0.160 |
23% |
84.8 |
Aperture |
Base |
Depth |
Dipole |
Dipole |
F/B |
F/B |
0.6 |
0.6 |
0.3 |
0.400 |
0.22 |
9.7 |
10.2 |
0.6 |
0.6 |
0.5 |
0.377 |
0.27 |
13.3 |
12.9 |
0.7 |
0.7 |
0.3 |
0.410 |
0.20 |
12.5 |
12.8 |
0.7 |
0.7 |
0.5 |
0.410 |
0.21 |
19.5 |
16.7 |
0.8 |
0.8 |
0.5 |
0.430 |
0.20 |
26.7 |
21.0 |
0.88 |
0.57 |
0.44 |
0.458 |
0.25 |
19.9 |
19.0 |
0.9 |
0.9 |
0.3 |
0.440 |
0.25 |
17.2 |
16.1 |
0.9 |
0.9 |
0.4 |
0.440 |
0.20 |
24.1 |
23.0 |
0.9 |
0.9 |
0.5 |
0.440 |
0.20 |
27.4 |
23.7 |
0.9 |
0.9 |
0.6 |
0.440 |
0.20 |
16.6 |
17.4 |
1.0 |
1.0 |
0.3 |
0.440 |
0.20 |
17.7 |
16.4 |
1.0 |
1.0 |
0.3 |
0.440 |
0.23 |
17.8 |
16.8 |
1.0 |
1.0 |
0.4 |
0.440 |
0.23 |
23.9 |
21.7 |
1.0 |
1.0 |
0.5 |
0.440 |
0.23 |
30.4 |
28.7 |
1.0 |
1.0 |
0.6 |
0.458 |
0.21 |
17.6 |
18.9 |
1.0 |
0.65 |
0.5 |
0.458 |
0.25 |
22.8 |
20.8 |
1.1 |
1.1 |
0.4 |
0.458 |
0.24 |
21.6 |
19.3 |
1.1 |
1.1 |
0.5 |
0.440 |
0.25 |
33.6 |
27.8 |
1.1 |
1.1 |
0.6 |
0.458 |
0.25 |
17.2 |
16.1 |
1.2 |
0.65 |
0.5 |
0.458 |
0.25 |
27.3 |
23.3 |
1.3 |
0.65 |
0.5 |
0.458 |
0.23 |
25.3 |
22.4 |
1.4 |
0.65 |
0.5 |
0.432 |
0.23 |
22.4 |
21.4 |
1.5 |
0.65 |
0.5 |
0.440 |
0.22 |
19.4 |
20.4 |
1.6 |
0.65 |
0.44 |
0.440 |
0.22 |
21.4 |
23.1 |
1.7 |
0.65 |
0.44 |
0.440 |
0.25 |
21.1 |
23.5 |
1.7 |
0.80 |
0.44 |
0.440 |
0.25 |
21.8 |
25.8 |
1.7 |
0.90 |
0.44 |
0.449 |
0.26 |
24.9 |
28.1 |
1.7 |
1.0 |
0.44 |
0.454 |
0.28 |
29.8 |
28.7 |
1.7 |
1.1 |
0.44 |
0.454 |
0.30 |
31.2 |
26.4 |
1.8 |
1.0 |
0.44 |
0.454 |
0.30 |
29.8 |
28.6 |