Geely EC715 2009, Workshop Manual

Page: 1524 / 2181

11.3.3 System Working Principle
11.3.3.1 Navigation System Principle Diagram
Antenna
Amplifier
Frequency Modifier
Vehicle Speed Sensor
Vehicle Speed Signal
Measure Calculate
Check Confirm
Calculate Vehicle
Current Position
Sensor
Calculate Direction Change
Map Matching
Map Database
Microprocessor
Display
Voice Output
Receiver
FE11-5202b
11.3.3.2 GPS System Positioning Principle
GPS system is used to determine the user's exact location on
Earth. each satellite rotate around the Earth two laps every day,
so at any location on Earth, four or more satellites signals can
be received at the same time. the computer can calculate the
user current location in Earth coordinates (longitude, latitude).
After the receiver receives these signals, it calculates the
current three-dimensional position, three-dimensional direction
and velocity and time information. GPS receivers are usually
used for pseudo-range measurements, carrier phase
measurements, satellite radio interferometry, Doppler
measurements and other measurements.
x
y
z
(x1
、
y1
、
z1)
(x2
、
y2
、
z2)
(x3 、 y3 、 z3)
(x4 、 y4 、 z4)
FE11-5203b
11-40 Navigation Body Electric
EC718/EC718RV EC715/EC715RV 10/2009