GPS

Question 1

How many satellites orbiting earth?

Answer 1

24

Question 2

What type of signal does it send?

Answer 2

Time signal

Question 3

What are some similar systems launched by Russia and Europe?

Answer 3

GLONASS (Russia) and Galileo (Europe)

Question 4

What does GPS technology provide?

Answer 4

Accurate location information

Question 5

What does GPS rely on?

Answer 5

It relies on a space-based network of satellites

Question 6

How is accuracy maintained?

Answer 6

By the control system

Question 7

GPS systems (3)

Answer 7

1. Space System
2. Control system
3. User system

Question 8

Space system:

Answer 8

24 satellites, 6 orbital tracks so at least 4 satellites per track. Provides a minimum of 5 to 8 satellites anywhere on earth.

Question 9

Orbit time of a satellite?

Answer 9

11 hours and 58 min

Question 10

What do GPS receivers convert satellite signals into?

Answer 10

It converts it into position, velocity, and time estimates. XYZ (position, location and velocity) and time.

Question 11

Control systems: What is the main purpose of control systems?

Answer 11

Is to maintain and update satellites

Question 12

What is selective availability?

Answer 12

is a system the government can use to degrade public accuracy.

Question 13

What are the 2 signals produced by the control systems?

Answer 13

SPS: Standard positioning service
and
PPS: Precise positioning service.

Question 14

User System:

Answer 14

Consists of GPS signal receivers.

Question 15

How can you improve accuracy?

Answer 15

Removal of selective availability and the use of different GPS receivers.

Question 16

What signal can consumer receivers not receive.

Answer 16

Consumer receivers cannot detect PPS.

Question 17

What is the equation the satellites use?

Answer 17

Trilateration

Question 18

What are some sources of errors of GPS?

Answer 18

1. Atmosphere/ionosphere
2. Atomic clock deviation on SV’s (small)
3. Non-direct signal path between SV and receiver
4. Receiver math
5. Geometry
6. Blocked line of sight (buildings)

Question 19

Geo-reference:

Answer 19

The act of coordinating collective data to a common global reference, other related topics included Geo-coding and address matching.

Question 20

Geographic Information Science:

Answer 20

The science related to examining and studying the technology associated with collecting, storing and processing spatial data. Research expands the technology.

Question 21

Geographic Information Studies:

Answer 21

Studies related to the societial cobntect of geographic information systems.

Question 22

Geographic information system?

Answer 22

The integrated hardware and software to collect, store and process spatial data.