7-9.2 Satoh Horn
The Satoh horn uses a dielectric cone inserted into a smooth-wall conical horn which generates the TM11 mode. The dielectric cone is placed so that corrugated performance is achieved. CHAMP (TICRA) can be used to design this horn through optimization of the parameters: gain at center frequency, maximum cross-polarization, and return loss over a small frequency range. The horn analysis uses an initial conical section from the waveguide to the dielectric cone solved by mode-matching. The rest of the horn is analyzed using BOR-MoM and includes the dielectric cone , the cone to the aperture, and the external surface of the horn. Figure 7-9.2-1 shows the location of the dielectric cone in the horn.
Figure 7-9.2-1 15 dB Gain Satoh Horn cross-section illustrating the dielectric cone (green) used to generate the TM11 mode
Table 7-9.2 lists parameters of Satoh horns designed by using the optimization of CHAMP.
Table 7-9.2 Parameters of Satoh Horns, using Teflon Cones
Gain dB |
Aperture Radius, λ |
Slant |
To Dielectric |
Dielectric Thickness |
Cone Length, λ |
25-dB |
10 dB Beam-width |
Phase Center, λ |
15 |
1.0465 |
6.9983 |
0.8455 |
0.1640 |
0.9674 |
12.2 |
61.7 |
3.169 |
16 |
1.1550 |
6.2879 |
0.4650 |
0.1782 |
0.9439 |
11.4 |
56.1 |
3.269 |
17 |
1.3452 |
6.7636 |
0.4495 |
0.1825 |
0.9322 |
13.5 |
49.3 |
3.759 |
18 |
1.4606 |
8.8020 |
1.0936 |
0.1294 |
0.9732 |
19.8 |
43.4 |
4.610 |
19 |
1.6719 |
9.8613 |
1.2722 |
0.1344 |
0.9555 |
19.2 |
38.8 |
5.174 |
20 |
1.8134 |
10.335 |
1.0933 |
0.1089 |
1.4908 |
15.2 |
34.7 |
6.363 |
21 |
2.2153 |
11.392 |
1.0235 |
0.1364 |
0.9489 |
20.3 |
30.4 |
5.864 |
22 |
2.7976 |
13.028 |
0.9524 |
0.1503 |
0.9343 |
19.7 |
27.2 |
5.823 |
23 |
3.0384 |
15.687 |
1.4148 |
0.1432 |
0.9746 |
15.2 |
24.3 |
8.414 |
The Satoh horn when optimized using CHAMP has about twice the cross-polarization bandwidth compared to the Potter horn with its single metal step.
A longer report along with a CHAMP test input file can be downloaded Step_Multi-mode_horns.zip.
20 dB Gain Satoh Horn Center Frequency Response (10 GHz)
20 dB Gain Satoh Horn Maximum Cross-polarization relative to Peak Response versus Frequency
37. T. Satoh, Dielectric Loaded Horn Antenna, IEEE Transactions on Antennas and Propagation,
vol. AP-20, no. 2, March 1972, pp. 199-201.