Page 177 - Intro to Space Sciences Spacecraft Applications

164 Zntmduction to Space Sciences and Spacecraft Applications
REFERENCEWADDITIONAL READING

Logsdon, T., The Navstar Global Positioning System. New York: Van
Nostrand Reinhold, 1992.
Dutton, L., Military Space. Great Britain: Brassey’s, 1990.
McElroy, J., Space Science and Applications. New York IEEE Press,
1986.
Cochran, C., Space Handbook. Alabama: Air University Press, 1985.

1. List and expound upon some of the benefits achieved by using naviga-
tion satellites.
2. Assuming a slant range to a GPS satellite of 20,000 km and a speed of
light of 3 x lo8 dsec, determine the range inaccuracy associated with
a 1 % error in time measurement between transmit and receive of a tim-
ing signal.
3. Using the parameters above, determine the time measurement accuracy
(percentage and number of seconds) required to achieve a 50-meter
slant range measurement capability.