midterm questions Flashcards
which of the following is not an example of a NAVigation system with Time and Ranging
Japan - Himawari
which of the following is an example of an absolute coordinate system
Geographic Coordinate System
advantages of using GPS do not include
can be used underground
which of the following is the master control station for gps
colorado spring
a gps satellite has three key pieces of hardware
computer, atomic clock, and radio transmitter
each satellite passes over at least one monitoring station _______ a day
twice
which of the following vector data structure was developed by USGS
DLG - digital line graph
which of the following values would you use for elevation mask on a gps receiver
15
north carolina state plane coordinate system uses
lambert confirmal conic projection
which of the following errors could not be eliminated using post-processing methods (such as differential correction)?
multipath
which of the following accurately describes the timekeeping mechanism aboard GPS satellites
each GPS satellite possesses four atomic clocks to maintain precise synchronization and reliability
which of the following values can be used for your PDOP mask setting on your gps receiver
6
thinking about GPS error sources, which of the following sources is not considered as random error
satellite clock
about the role GPS base station, which statement is correct
it provides correction signals to rovers
about Circular Error Probable (CEP), which of the following statements is correct?
75% of the fixes will fall within the CEP circle, and 25% outside
about 2DRMS (similar to CEP), which statement below is correct
with 2DRMS, 95% of the fixes will lie within a circle with this radius
DOP stands for
dilution of precision
____________ can achieve centimeter or millimeter level accuracy
Only C
C. Survey Grade GPS
____________ are used to control gps movements and maintain accurate system setting (such as removing clock errors)
GPS ground stations
Which of the following best describes the relationship between the distance from a gps receiver to a base station and the resulting error in fix accuracy
the error increases linearly with the distance between the receiver and the base station
which type of orbit is frequently utilized for navigation systems such as the US GPS?
Medium Earth Orbit (MEO)
in which order were the following navigation system with time and ranging (NAVSTAR) constellations established, earliest to latest
GPS, Glonass, Galileo, Beidou, Qzss, Navic
which organization is responsible for creating the most popular topographic maps for use within the US
USGS United States Geological Survey
please explain the role of gps upload stations
what are almanac and ephemeris? what is the difference between them
describe the mechanism by which GPS receivers are able to simultaneously receive signals from multiple satellites
design a GPS project to compare accuracies of different types of GPS receivers such as mapping vs recreational grade receivers.
what method does the GPS receiver employ to estimate the travel time of GPS signals? can you determine the distance between the satellite and receiver when the signal is sent at 4:00:00 and received at 4:00:07
describe the major factors that contribute to error of GPS measurements, and how would you avoid them
what is differential correction, how would you select base stations, and how would you set up your own base station
