A GPS receiver, or GPS sensor, is able to determine its position and velocity ______ the earth’s surface by calculating the amount of time it takes for signals from different GPS satellites to reach the receiver.
A: on top of
B: next to
C: in spite of
D: relative to
A: on top of
B: next to
C: in spite of
D: relative to
举一反三
- GPS satellites send signal information, such as time, position of satellite, position of receiver, and traffic condition on the earth.
- The GPS receiver is able to receive signals that are transmitted by stars orbiting overhead.
- 6. GPS determines location by computing the difference between the time a signal is sent and the time is received. GPS satellites carry ______ that provide extremely accurate time. The time information is placed in the codes broadcast by the satellite so that a receiver can continuously determine the time the signal was broadcast.
- accuracy of GPS receiver
- It is possible to use satellites to predict earthquakes because satellites ________. A: take pictures of the Earth B: catch radio waves sent from the Earth’s surface C: are sensitive to Earth’s movements D: see almost the entire Earth