Parallax VPN1513, Руководство пользователя

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The Specifications are subject to be changed without notice. Copyright © 2007, GlobalSat Technology. Page 9 of 27
2.
GPS POWER
VIN GPS_3V3
L1
Layout Rule
Do not routing the other signal or power trace under the engine board .
* RF:
This pin receives signal of GPS analog via external active antenna .It has to be a controlled impedance
trace at 50ohm. Do not have RF traces closed the other signal path and routing it on the top layer.Keep the
RF traces as short as possible.
* Antenna:
Keep the active antenna on the top of your system and confirm the antenna radiation pattern
、
axial ratio
、
power gain
、
noise figure
、
VSWR are correct when you Setup the antenna in you case.
GPS Passive (or Active )Antenna Specification(Recommendation)
Frequency: 1575.42±2 MHz
Axial Ratio: 3 dB Typical
output Impedance: 50
Ω
Polarization: RHCP
Output VSWR: 1.5 Max.
Active option
Low Noise Amplifier:
Amplifier Gain :18~22dB Typical
Output VSWR: 2.0 Max.
Noise Figure: 2.0 dB Max.
Antenna Input Voltage : 2.85V(Typ.)
Definition of Pin assignment
VCC
This is the main DC supply for a 3.3V ± 5% DC input power module board.
GND