Self-Test
& Supply the missing word(s) in each statement.
Choose the letter that best answers each question.
1. A satellite is kept in orbit by a balance between two forces: _____.
2. A satellite that revolves in the same direction as the earth rotates is said to be in a _____ (posigrade, retrograde) orbit.
3. The geometric shape of a noncircular orbit is a(n) _____.
4. The center of gravity of the earth is called the _____.
5. The time for one orbit is called the _____.
6. The angle of inclination of a satellite is _____ degrees if it orbits over the equator and is _____ degrees if it orbits over the north and south poles.
7. To prevent excessive signal attenuation and noise in the atmosphere, satellite angles of elevation of less than _____ degrees should be avoided.
8. A satellite that rotates around the equator 22,300 mi from the earth is said to be in _____ orbit.
9. Small jet thrusters on a satellite are fired to correct the satelIite's _____.
10. Name two ways satellites are stabilized in space.
11. The three axes of a satellite are _____.
12. The point on the earth directly below a satellite is called the _____.
13. Satellites are located by earth coordinates expressed in terms of _____.
14. The two angles used to point a ground station antenna are _____.
15. A satellite is put into final geosynchronous orbit from its transfer orbit by firing the _____.
16. The most common use of a satellite is _____.
17. A communications satellite is basically a radio _____.
18. A(n) _____ transmits an up-link signal to the satellite.
19. The signal path from a satellite to a ground station is called the _____.
20. The basic communications electronics unit on a satellite is known as a(n) _____.
21. Most communications satellites operate in the _____ frequency range.
22. The most popular satellite frequency range is 4 to 6 GHz and is called the _____ band.
23. Military satellites often operate in the _____ band.
24. The Ku band extends from _____ to _____ GHz.
25. The bandwidth of a typical satellite is _____ MHz.
26. A typical C band transponder can carry _____ channels, each with a bandwidth of _____ MHz.
27. The term used to refer to the technique of using antenna polarization to separate signals on the same frequency to double the number of channels is _____.
28. Using very narrow beam width antennas to isolate signals on the same frequency is known as _____.
29. The most common baseband signals handled by a satellite are _____.
30. The input circuit to a transponder is the _____.
31. List the three main functions of a transponder.
32. A(n) _____ circuit in the transponder performs the frequency conversion.
33. Power amplification in a transponder is usually provided by a(n) _____.
34. A(n) _____ transponder provides amplification at an IF of 70 or 150 MHz.
35. A transponder that demodulates the baseband signals and then remodulates a carrier is known as a(n) _____ transponder.
36. The circuit that provides channelization in a transponder is the _____.
37. The two basic architectures for multichannel transponders are _____.
38. The main power supplies in a satellite are the _____.
39. During an eclipse, the satellite is powered by _____.
40. The TTC subsystem is used to _____ operations on a satellite.
41. Attitude correction is made by firing _____.
42. The signals to be communicated by' the earth station to the satellite are known as _____ signals.
43. The receive or up-link subsystem uses a _____ to translate the satellite signal to an IF before demodulation and demultiplexing.
44. A common IF in an earth station receiver is _____ MHz.
45. The functions performed by the receive GCE section are _____.
46. The functions performed by the transmit GCE section are _____.
47. The two types of modulation used in the transmit GeE are _____.
48. A(n) _____ in the transmit subsection translates the modulated signal to the final transmission frequency.
49. _____ are often used to replace Los for channel selection in earth station transmitters and receivers.
50. List the three main types of power amplifiers used in earth stations.
51. Most earth stations operate from the ac power line but have built-in _____ for emergency operation.
52. True or false. All earth stations contain telemetry, control, and instrumentation subsystems.
53. The main use of satellites is for _____.
54. Name four types of surveillance sensors.
55. What are the name and the purpose of the 24-satellite system developed by the military?
56. Name three uses for surveillance satellites.
Consumers use satellites for _____.
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