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Дата изменения: Unknown Дата индексирования: Tue Oct 2 07:30:26 2012 Кодировка: |
Latitude (geodetic1) | 18° 20' 36.6" North |
Longitude (geodetic1) | 66° 45' 11.1" West |
Latitude (astronomical) | 18° 21' 13.7" North |
Longitude (astronomical) | 66° 45' 18.8" West |
Declination range | -01:24:00 through +38:00:00 |
Azimuth Slew Rate | 0.4 deg/s, 1440 deg/hour |
Elevation Slew Rate | 0.04 deg/s, 144.0 deg/hour |
Zenith angle range | 1.06 - 19.69 degrees |
Magnetic Dip | 50° |
Magnetic declination | 8° 30' West |
Height of reflector center of curvature above MSL | 1630 ft (497 m) |
1Earth Ellipsoid "Mercury 1960", with semimajor axis 6378166 m and inverse flattening 298.3
Type | Fixed reflector, movable feeds |
Diameter of reflector | 1000 ft (304.8 m) |
Area of aperture | 18 acres (73,000 sqare m) |
Shape of surface | 70° spherical cap |
Radius of curvature | 870 ft (265 m) |
Surface accuracy | 2.2 mm rms |
- |
Effective Aperture |
Forward Gain |
|||
Freq. (MHZ) |
ZA = 15° |
ZA = 20° |
ZA = 15° |
ZA = 20° |
|
327 |
10.5 K/Jy |
9 K/Jy |
55.5 dB |
53.1 dB |
|
430 |
11 K/Jy |
10 K/Jy |
55.5 dB |
55.5 dB |
|
610 |
11 K/Jy |
10 K/Jy |
60.9 dB |
|
|
1400 |
11 K/Jy |
10 K/Jy |
68.3 dB |
67.2 dB |
|
2380 |
10 K/Jy |
8 K/Jy |
72.4 dB |
71.2 dB |
|
3300 |
8 K/Jy |
6 K/Jy |
|||
5000 |
7 K/Jy |
5.5 K/Jy |
78.3 dB |
76.8 dB |
|
7000 |
4.5 K/Jy |
4 K/Jy |
|
|
|
8500 |
4 K/Jy |
3 K/Jy |
Noise Contributions ( excluding receiver noise ) |
||
- |
ZA = 15° |
ZA = 20° |
Spillover |
4 K |
6 K |
Blockage |
4 K |
4 K |
Atmosphere |
3 K |
3 K |
Cosmic Background |
3 K |
3 K |
Total |
14 K |
16 K |
Peak Sidelobe Level ( with blockage ) |
||
- |
ZA = 15° |
ZA = 20° |
250 MHz |
- 12.2 dB |
- 11.2 dB |
500 MHz |
- 13.5 dB |
- 12.5 dB |
1000 MHz |
- 15.1 dB |
- 14.2 dB |
5000 MHz |
- 16.0 dB |
- 15.0 dB |
- |
ZA = 15° | ZA = 20° | |
Cross - Polarization | - 28 dB |
------ |
------ |
Beam Squint | Circular Pol. | 0.01 HPBW |
------ |
Feed Cluster Size | 430 MHz | 1 |
------ |
( see discussion ) | 1400 MHz | 3 ( or 7, without 1 dB gain reduction ) | |
- |
5000 MHz | 7 |
------ |
1 One Kelvin/Jansky (K/Jy) corresponds to 2761 m2 effective aperture.