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ssrs 2014 barcode The Geostationary Orbit in Software
The Geostationary Orbit Recognizing QRCode In None Using Barcode Control SDK for Software Control to generate, create, read, scan barcode image in Software applications. Making QR Code In None Using Barcode generator for Software Control to generate, create QR Code image in Software applications. to compensate for the movement of the satellite about the nominal geostationary position. With the types of antennas used for home reception, the antenna beamwidth is quite broad, and no tracking is necessary. This allows the antenna to be fixed in position, as evidenced by the small antennas used for reception of satellite TV that can be seen fixed to the sides of homes. The three pieces of information that are needed to determine the look angles for the geostationary orbit are 1. The earthstation latitude, denoted here by lE 2. The earthstation longitude, denoted here by fE 3. The longitude of the subsatellite point, denoted here by fSS (often this is just referred to as the satellite longitude) As in Chap. 2, latitudes north will be taken as positive angles, and latitudes south, as negative angles. Longitudes east of the Greenwich meridian will be taken as positive angles, and longitudes west, as negative angles. For example, if a latitude of 40 S is specified, this will be taken as 40 , and if a longitude of 35 W is specified, this will be taken as 35 . In Chap. 2, when calculating the look angles for lowearthorbit (LEO) satellites, it was necessary to take into account the variation in earth s radius. With the geostationary orbit, this variation has negligible effect on the look angles, and the average radius of the earth will be used. Denoting this by R: R 6371 km (3.5) QR Code 2d Barcode Scanner In None Using Barcode scanner for Software Control to read, scan read, scan image in Software applications. Painting QR Code In Visual C#.NET Using Barcode generation for .NET framework Control to generate, create QR Code ISO/IEC18004 image in .NET framework applications. The geometry involving these quantities is shown in Fig. 3.1. Here, ES denotes the position of the earth station, SS the subsatellite point, S the satellite, and d is the range from the earth station to the satellite. The angle is an angle to be determined. There are two types of triangles involved in the geometry of Fig. 3.1, the spherical triangle shown in heavy outline in Fig. 3.2a and the plane triangle of Fig. 3.2b. Considering first the spherical triangle, the sides are all arcs of great circles, and these sides are defined by the angles subtended by them at the center of the earth. Side a is the angle between the radius to the north pole and the radius to the subsatellite point, and it is seen that a 90 . A spherical triangle in which one side is 90 is called a quadrantal triangle. Angle b is the angle between the radius to the earth station and the radius to the subsatellite point. Angle c is the angle between the radius to the earth station and the radius to the north pole. From Fig. 3.2a it is seen that c 90 lE. QR Code JIS X 0510 Printer In VS .NET Using Barcode drawer for ASP.NET Control to generate, create Quick Response Code image in ASP.NET applications. Encode Quick Response Code In .NET Using Barcode maker for .NET Control to generate, create Quick Response Code image in .NET framework applications. Three
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2/5 Interleaved Encoder In None Using Barcode creation for Software Control to generate, create I2/5 image in Software applications. ECC200 Generator In Java Using Barcode encoder for Java Control to generate, create ECC200 image in Java applications. There are six angles in all defining the spherical triangle. The three angles A, B, and C are the angles between the planes. Angle A is the angle between the plane containing c and the plane containing b. Angle B is the angle between the plane containing c and the plane containing a. From Universal Product Code Version A Creation In .NET Framework Using Barcode generation for Reporting Service Control to generate, create UPCA image in Reporting Service applications. Code 128 Code Set A Reader In None Using Barcode decoder for Software Control to read, scan read, scan image in Software applications. c A B a b C
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ANSI/AIM Code 39 Generation In None Using Barcode encoder for Online Control to generate, create USS Code 39 image in Online applications. Code 128B Decoder In .NET Framework Using Barcode reader for .NET Control to read, scan read, scan image in .NET framework applications. Figure 3.2 (a) The spherical geometry related to Fig. 3.1. (b) The plane triangle s obtained from Fig. 3.1. aGSO = aE + h
The Geostationary Orbit
Fig. 3.2a, B E SS. It will be shown shortly that the maximum value of B is 81.3 . Angle C is the angle between the plane containing b and the plane containing a. To summarize to this point, the information known about the spherical triangle is a c B 90 90 (3.6) lE
(3.7) (3.8) Note that when the earth station is west of the subsatellite point, B is negative, and when east, B is positive. When the earthstation latitude is north, c is less than 90 , and when south, c is greater than 90 . Special rules, known as Napier s rules, are used to solve the spherical triangle (see Wertz, 1984), and these have been modified here to take into account the signed angles B and lE. Only the result will be stated here. Napier s rules gives angle b as b 5 arccoss cos B cos lEd and angle A as A 5 arcsina sin Z B Z b sin b (3.10) (3.9) Two values will satisfy Eq. (3.10), A and 180 A, and these must be determined by inspection. These are shown in Fig. 3.3. In Fig. 3.3a, angle A is acute (less than 90 ), and the azimuth angle is Az A. In Fig. 3.3b, angle A is acute, and the azimuth is, by inspection, Az 360 A. In Fig. 3.3c, angle Ac is obtuse and is given by Ac 180 A, where A is the acute value obtained from Eq. (3.10). Again, by inspection, Az Ac 180 A. In Fig. 3.3d, angle Ad is obtuse and is given by 180 A, where A is the acute value obtained from Eq. (3.10). By inspection, Az 360 Ad 180 A. In all cases, A is the acute angle returned by Eq. (3.10). These conditions are summarized in Table 3.1.

