(a) Aural broadcast STL and ICR stations are required to use a directional antenna with the minimum beamwidth necessary, consistent with good engineering practice, to establish the link.
(b) An aural broadcast STL or intercity relay station operating in the 17.7-19.7 GHz band shall employ an antenna that meets the performance standards for Category A, except that in areas not subject to frequency congestion, antennas meeting standards for Category B may be employed. However, the Commission may require the replacement, at the licensee's expense, of any antenna or periscope antenna system of a permanent fixed station that does not meet performance Standard A, which is specified in the table in paragraph (c) of this section, upon a showing that said antenna causes or is likely to cause interference to (or receive interference from) any other authorized or proposed station; provided that an antenna meeting performance Standard A is unlikely to involve such interference.
(c) Licensees shall comply with the antenna standards table shown in this paragraph in the following manner:
(1) With either the maximum beamwidth to 3 dB points requirement or with the minimum antenna gain requirement; and
(2) With the minimum radiation suppression to angle requirement.
| Frequency (GHz)
| Category
| Maximum beamwidth to 3 dB points
1
(included angle in
degrees)
| Minimum antenna gain (dbi)
| Minimum radiation suppression to angle in degrees from centerline of main beam in decibels
|
|---|
| 5° to 10°
| 10° to 15°
| 15° to 20°
| 20° to 30°
| 30° to 100°
| 100° to 140°
| 140° to 180°
|
|---|
| 17.7 to 19.7 | A
B | 2.2
2.2 | 38
38 | 25
20 | 29
24 | 33
28 | 36
32 | 42
35 | 55
36 | 55
36
|