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GLONASS Satellite Constellation
GLONASS is a radio-based satellite navigation system operated for the Russian government by the Russian Aerospace Defense Forces.
clc; clear all; fname = 'Glonass.txt'; % TLE file name Earth3DPlot(1); % Open the TLE file and read TLE elements fid = fopen(fname, 'rb'); while ~feof(fid) [ h, i, RAAN, e,omega,theta ] = TLE2OE( fid ); [Rv, alfa,delta ] = J2PropagR( h, i, RAAN, e,omega,theta) ; scatter3(Rv(:,1),Rv(:,2),Rv(:,3),'.'); end fclose(fid); % Ground Track EarthTopographicMap(2,820,420); fid = fopen(fname, 'rb'); while ~feof(fid) [ h, i, RAAN, e,omega,theta ] = TLE2OE( fid ); [Rv, alfa,delta ] = J2PropagR( h, i, RAAN, e,omega,theta) ; scatter(alfa,delta,'.'); end fclose(fid); text(280,-80,'smallsats.org','Color',[1 1 1], 'VerticalAlignment','middle',... 'HorizontalAlignment','left','FontSize',14 ); title('GLONASS Satellite Constellation');
TLE Data Source. http://www.celestrak.com/ January 20, 2012
GPS Satellite Constellation
The Global Positioning System (GPS) is a space-based satellite navigation system that provides location and time information in all weather conditions, anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites.
clc; clear all; fname = 'GPS.txt'; % TLE file name Earth3DPlot(1); % Open the TLE file and read TLE elements fid = fopen(fname, 'rb'); while ~feof(fid) [ h, i, RAAN, e,omega,theta ] = TLE2OE( fid ); [Rv, alfa,delta ] = J2PropagR( h, i, RAAN, e,omega,theta) ; scatter3(Rv(:,1),Rv(:,2),Rv(:,3),'.'); end fclose(fid); % Ground Track EarthTopographicMap(2,820,420); fid = fopen(fname, 'rb'); while ~feof(fid) [ h, i, RAAN, e,omega,theta ] = TLE2OE( fid ); [Rv, alfa,delta ] = J2PropagR( h, i, RAAN, e,omega,theta) ; scatter(alfa,delta,'.'); end fclose(fid); text(280,-80,'smallsats.org','Color',[1 1 1], 'VerticalAlignment','middle',... 'HorizontalAlignment','left','FontSize',14 ); title('GPS Satellite Constellation');
TLE Data Source. http://www.celestrak.com/ January 20, 2012
GPS BIIA-10 (PRN 32) 1 20959U 90103A 13018.84945698 .00000048 00000-0 10000-3 0 8427 2 20959 54.4303 229.9128 0117665 335.2539 24.2342 2.00550891162214 GPS BIIA-14 (PRN 26) 1 22014U 92039A 13019.14607454 -.00000071 00000-0 10000-3 0 6346 2 22014 56.1801 290.1218 0208290 69.5584 292.7075 2.00565875143955 GPS BIIA-15 (PRN 27) 1 22108U 92058A 13018.75434799 -.00000089 00000-0 10000-3 0 5581 2 22108 56.2534 343.0502 0222435 303.9410 53.9615 2.00569608149127 GPS BIIA-21 (PRN 09) 1 22700U 93042A 13018.74470584 -.00000088 00000-0 00000+0 0 8817 2 22700 56.4056 344.6226 0167916 93.9179 268.0033 2.00662093143282 GPS BIIA-22 (PRN 30) 1 22779U 93054A 13018.51983509 -.00000069 00000-0 10000-3 0 5571 2 22779 55.1533 39.1818 0106140 92.6721 268.5873 2.00571221142039 GPS BIIA-23 (PRN 04) 1 22877U 93068A 13018.41796082 .00000048 00000-0 10000-3 0 2373 2 22877 53.7295 164.7980 0102485 54.0859 306.8291 2.00556733140921 GPS BIIA-24 (PRN 06) 1 23027U 94016A 13018.12046811 -.00000048 00000-0 10000-3 0 1955 2 23027 53.8565 101.4536 0076290 335.9203 23.7554 2.00561802138223 GPS BIIA-25 (PRN 03) 1 23833U 96019A 13019.13913939 -.00000060 00000-0 10000-3 0 3935 2 23833 53.4736 96.9153 0157826 72.6851 289.0689 2.00564035123227 GPS BIIA-26 (PRN 10) 1 23953U 96041A 13018.50101030 .00000050 00000-0 10000-3 0 8803 2 23953 54.1034 225.9914 0120793 44.6889 316.3194 2.00554012121004 GPS BIIR-2 (PRN 13) 1 24876U 97035A 13019.00325574 -.00000072 00000-0 10000-3 0 3517 2 24876 56.3255 290.5219 0046517 120.2494 240.2582 2.00575732113546 GPS BIIA-28 (PRN 08) 1 25030U 97067A 13019.63536166 -.00000082 00000-0 10000-3 0 2975 2 25030 57.1991 351.0337 0128256 195.9414 163.6595 2.00570836111451 GPS BIIR-3 (PRN 11) 1 25933U 99055A 13019.25617045 .00000010 00000-0 10000-3 0 7874 2 25933 50.9146 148.4260 0136447 65.1740 296.2085 2.00561387 97361 GPS BIIR-4 (PRN 20) 1 26360U 00025A 13016.87981762 .00000037 00000-0 10000-3 0 8761 2 26360 53.2134 222.1388 0052448 73.0764 287.5347 2.00576559 93011 GPS BIIR-5 (PRN 28) 1 26407U 00040A 13019.21994987 -.00000062 00000-0 10000-3 0 8291 2 26407 56.2531 48.0068 0187923 257.4922 100.4450 2.00568287 91732 GPS BIIR-6 (PRN 14) 1 26605U 00071A 13018.81568033 -.00000070 00000-0 10000-3 0 8445 2 26605 55.9113 288.9048 0069360 245.5421 113.7790 2.00561684 89323 GPS BIIR-7 (PRN 18) 1 26690U 01004A 13018.69048158 .00000051 00000-0 10000-3 0 7237 2 26690 53.1752 225.1291 0138193 238.6253 120.0544 2.00553471 87732 GPS BIIR-8 (PRN 16) 1 27663U 03005A 13019.05927186 -.00000062 00000-0 10000-3 0 1540 2 27663 56.3455 47.6478 0068033 359.8082 0.2361 2.00576901 73096 GPS BIIR-9 (PRN 21) 1 27704U 03010A 13018.60667007 .00000047 00000-0 10000-3 0 377 2 27704 53.3697 165.0440 0198594 235.2103 122.8804 2.00553928 71879 GPS BIIR-10 (PRN 22) 1 28129U 03058A 13018.73549856 .00000051 00000-0 10000-3 0 6108 2 28129 53.0451 225.2919 0063340 244.9211 114.4621 2.00564098 66589 GPS BIIR-11 (PRN 19) 1 28190U 04009A 13019.17516771 -.00000046 00000-0 10000-3 0 6040 2 28190 55.1066 110.1249 0086959 14.6182 345.6476 2.00565996 64762 GPS BIIR-12 (PRN 23) 1 28361U 04023A 13018.96324076 -.00000066 00000-0 10000-3 0 4238 2 28361 54.8505 285.6669 0081990 194.9306 164.8791 2.00552385 62846 GPS BIIR-13 (PRN 02) 1 28474U 04045A 13018.96367060 .00000044 00000-0 10000-3 0 3107 2 28474 53.7850 163.8242 0119722 206.9062 152.4399 2.00573321 60202 GPS BIIRM-1 (PRN 17) 1 28874U 05038A 13018.32217387 -.00000042 00000-0 10000-3 0 5695 2 28874 55.2624 107.1585 0081479 231.4916 127.7975 2.00551100 53614 GPS BIIRM-2 (PRN 31) 1 29486U 06042A 13018.93123473 -.00000087 00000-0 10000-3 0 9604 2 29486 56.1978 346.2221 0082935 312.3064 46.9875 2.00549243 46326 GPS BIIRM-3 (PRN 12) 1 29601U 06052A 13019.37101994 -.00000060 00000-0 10000-3 0 9912 2 29601 56.3013 46.5841 0041062 4.7967 355.2950 2.00567097 45242 GPS BIIRM-4 (PRN 15) 1 32260U 07047A 13018.68384066 -.00000063 00000-0 00000+0 0 6980 2 32260 54.0003 283.4336 0051688 4.0264 356.0623 2.00561108 38627 GPS BIIRM-5 (PRN 29) 1 32384U 07062A 13018.50083400 -.00000043 00000-0 10000-3 0 7369 2 32384 55.2952 107.6507 0020298 293.2614 66.5488 2.00557842 37341 GPS BIIRM-6 (PRN 07) 1 32711U 08012A 13019.09384597 -.00000088 00000-0 10000-3 0 4945 2 32711 55.9093 345.9893 0061210 195.1431 164.6734 2.00559437 35567 GPS BIIRM-8 (PRN 05) 1 35752U 09043A 13018.56516204 .00000053 00000-0 10000-3 0 2489 2 35752 54.3995 224.8319 0030098 13.9303 346.1949 2.00578808 25132 GPS BIIF-1 (PRN 25) 1 36585U 10022A 13018.91284136 -.00000065 00000-0 10000-3 0 648 2 36585 55.6614 44.4964 0018446 28.7965 331.3534 2.00571492 19380 GPS BIIF-2 (PRN 01) 1 37753U 11036A 13019.28928872 .00000046 00000-0 00000+0 0 5261 2 37753 55.0147 164.8917 0014277 20.5806 339.4484 2.00559276 11077 GPS BIIF-3 (PRN 24) 1 38833U 12053A 13018.77758384 -.00000091 00000-0 00000+0 0 731 2 38833 54.9671 344.4909 0005362 333.1108 26.8609 2.00559339 2129
Satellite Ground Track, GPS BII-10
The Global Positioning System (GPS) is a space-based satellite navigation system that provides location and time information in all weather conditions, anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites. In this example we implement algorithm to plot GPS ground track. Same algorithm could be used for any satellite.
clear all; clc; % Earth topographic map figure(1); xwidth = 820; ywidth = 420; hFig = figure(1); set(gcf,'PaperPositionMode','auto') set(hFig, 'Position', [100 100 xwidth ywidth]) hold on; grid on; axis([0 360 -90 90]); load('topo.mat','topo','topomap1'); contour(0:359,-89:90,topo,[0 0],'b') axis equal box on set(gca,'XLim',[0 360],'YLim',[-90 90], ... 'XTick',[0 60 120 180 240 300 360], ... 'Ytick',[-90 -60 -30 0 30 60 90]); image([0 360],[-90 90],topo,'CDataMapping', 'scaled'); colormap(topomap1); ylabel('Latitude [deg]'); xlabel('Longitude [deg]'); title('GPS BII-10 ground track'); R_e = 6378; % Earth's radius mu = 398600; % Earth’s gravitational parameter [km^3/s^2] J2 = 0.0010836; we = 360*(1 + 1/365.25)/(3600*24); % Earth's rotation [deg/s] % GPS BII-10 Orbital Parametres rp = 19781 + R_e; % [km] Perigee Radius ra = 20582 + R_e; % [km] Apogee Radius theta = 25; % [deg] True anomaly RAAN = 229.9128 ; % [deg] Right ascension of the ascending node i = 54.4303 ; % [deg] Inclination omega = 335.2539 ; % [deg] Argument of perigee a = (ra+rp)/2; % Semimajor axis e = (ra -rp)/(ra+rp) ; % Eccentricity h = (mu*rp*(1 + e))^0.5; % Angular momentum T = 2*pi*a^1.5/mu^0.5; % Period dRAAN = -(1.5*mu^0.5*J2*R_e^2/((1-e^2)*a^3.5))*cosd(i)*180/pi; domega = dRAAN*(2.5*sind(i)^2 - 2)/cosd(i); % Initial state [R0 V0] = Orbital2State( h, i, RAAN, e,omega,theta); [ alfa0 ,delta0 ] = R2RA_Dec( R0 ); scatter(alfa0,delta0,'*k'); ind = 1; eps = 1E-9; dt = 20; % time step [sec] ti = 0; while(ti <= 3*T); E = 2*atan(tand(theta/2)*((1-e)/(1+e))^0.5); M = E - e*sin(E); t0 = M/(2*pi)*T; t = t0 + dt; M = 2*pi*t/T; E = keplerEq(M,e,eps); theta = 2*atan(tan(E/2)*((1+e)/(1-e))^0.5)*180/pi; RAAN = RAAN + dRAAN*dt ; omega = omega + domega*dt; [R V] = Orbital2State( h, i, RAAN, e,omega,theta); % Considering Earth's rotation fi_earth = we*ti; Rot = [cosd(fi_earth), sind(fi_earth),0;... -sind(fi_earth),cosd(fi_earth),0;0,0,1]; R = Rot*R; [ alfa(ind) ,delta(ind) ] = R2RA_Dec( R ); ti = ti+dt; ind = ind + 1; end scatter(alfa,delta,'.r'); text(280,-80,'smallsats.org','Color',[1 1 1], 'VerticalAlignment','middle',... 'HorizontalAlignment','left','FontSize',14 );
Small Satellites 