1. Attitude
The longer I live, the more I realize the impact of attitude on life. Attitude, to me, is more important than facts. It is more important than the past, than education, than money, than circumstances, than failures, than successes, than what other people think or say or do. It is more important than appearance, giftedness or skills. It will make or break a company...a church...a home. The remarkable thing is we have a choice every day regarding the attitude we will embrace for that day. We cannot change the inevitable. The only thing we can do is play on the one string we have, and that is our attitude...I am convinced that life is 10% what happens to me and 90% how I react to it. And so it is with you...we are in charge of our attitudes.
Charles Swindoll
(Widely published Christian minister; 2000)
Whatever happens in the life of a person, if his attitude is right, the Lord will work that experience for that person’s good.
Elder Dennis B. Neuenschwander
Faculty Inservice, Orem Institute of Religion, Dec 14, 1996
At the center of our agency is our freedom to form a healthy attitude toward whatever circumstances we are placed in!
Elder Neal A. Maxwell
Deposition of a Disciple (1976), 30–31.
IT Schweber Chap 19

2. Satellite Communication, Navigation & the Global Positioning System
Schweber, Chap 19:
Satellite Communication, Navigation & the Global Positioning System
IT Schweber Chap 19

3. Orbits LEO: typically 17,000 mph MEO: typically 12,000 mph
GEO: exactly 7070 mph
IT Schweber Chap 19

4. Frequency Bands
IT Schweber Chap 19

5. Factoids VERY complex systems Yes, it IS rocket science
High-frequency, high attenuation signals & electronics
Mechanical systems that must work in extreme conditions
Complicated and expensive Earth-based systems
Typical launch weight of 100s to 1000s of lbs
Typical cost of $50M to $100M (to build the satellite)
Launch cost of about $10,000/lb (LEO); MEO and GEO raise that another 5x each
10-year expected lifetime
IT Schweber Chap 19

6. Link Budget
IT Schweber Chap 19

7. How Many? (www.n2yo.com) IT 327 - Schweber Chap 19
Satellite Totals - Most to Least
Geostationary
816
Military
565
Strela
546
Space & Earth Science
475 TV
375
No Category
169
CubeSats
146
Glonass Operational
128
Earth Resources
115
Parus 95
Iridium 92
Experimental 87
Globalstar 84
Weather 79
Amateur Radio 76
Intelsat 68
Tselina 65
GPS Operational 64
Engineering 59
Westford Needles 48
Rudaga 44
Molniya
Orbcomm 43
Brightest 37
Navy Navigation Satellite System
Gorizont 33
Tracking & Data Relay Satellite System 31
Tsiklon 28
Geodectic 26
Yaogan 25
Radar Calibration 24
Disaster Monitoring 22
NOAA 20
Beidou Navigation System
Tsikada
Education 17
Sfera
Russian LEO Navigation 16
GOES 15
Search & Rescue
Satellite-Based Augmentation System 14
Gonets 12
XM & Sirius 9
ISS 8
Galileo 6
TOTAL
4735
Satellite Totals - by Category
Amateur Radio 76
Beidou Navigation System 20
Brightest 37
CubeSats
146
Disaster Monitoring 22
Earth Resources
115
Education 17
Engineering 59
Experimental 87
Galileo 6
Geodectic 26
Geostationary
816
Globalstar 84
Glonass Operational
128
GOES 15
Gonets 12
Gorizont 33
GPS Operational 64
Intelsat 68
Iridium 92
ISS 8
Military
565
Molniya 44
Navy Navigation Satellite System
No Category
169
NOAA
Orbcomm 43
Parus 95
Radar Calibration 24
Rudaga
Russian LEO Navigation 16
Satellite-Based Augmentation System 14
Search & Rescue
Sfera
Space & Earth Science
475
Strela
546
Tracking & Data Relay Satellite System 31
Tselina 65
Tsikada
Tsiklon 28 TV
375
Weather 79
Westford Needles 48
XM & Sirius 9
Yaogan 25
TOTAL
4735
How Many? (
IT Schweber Chap 19

8. Too Many? (http://www.youtube.com/watch?v=_o7EKlqCE20)
IT Schweber Chap 19

9. Navigation: A True Story
Commodore Anson and the Centurion
In September 1740, the H.M.S. Centurion set sail for the South Pacific from England under the command of Commodore George Anson. They had no chronometer. By March, 1741, already 6 months at sea, the Centurion rounded the tip of Cape Horn, only to encounter a terrific storm that punished them for 58 days. When finally able to get a fix on their position, Anson sailed north and west for Juan Fernández Island for some desperately needed fresh water and food. When he reached the proper latitude, he had no idea which way to go – east or west. For over two months they had been unable to plot their progress, and they did not have a chronometer to allow them to determine their longitude. So on a hunch, he sailed west. But after not sighting land after four days, he decided he was already west of Juan Fernández, so they turned around and headed east.
Two days later, they sighted land, but it turned out to be the coast of Chile, under Spanish rule; they could not go there! So they executed another quick 180° turn and sailed west again. Finally, on June 9, 1741, they dropped anchor at Juan Fernández. The extra two weeks of sailing had cost Anson an additional 80 lives among his sick and ailing crew.
Longitude, by Dava Sobel (Walker & Co., 1995), pp 17-20
IT Schweber Chap 19

10. LORAN (LOng RAnge Navigation)
IT Schweber Chap 19

11. GPS
IT Schweber Chap 19

12. GPS
IT Schweber Chap 19