Gps Rf General Checking - Nokia NPD-4 Series Troubleshooting - Gps

NPD-4
Troubleshooting — GPS
GPS Antenna Spring Clips

GPS RF General Checking

The fastest way to get an overview of GPS RF status is to run GPS QUICK TEST. This can
be done by using a CW signal generator and Phoenix. When running Galvanic testing, set
signal generator frequency to 1575.520152 MHz and adjust level to -110 dBm at GPS
antenna port. In radiated testing CW level has to be higher, because of the attenuation in
pad + cable + coupler. With -20 dB pad signal level in signal generator is ~ -110 dBm +
cable attenuation + 20 dB + 18 dB.
The CW analysis is functionality has been added to the GPS to allow end-to-end spectral
purity to be assessed during manufacturing and development.
1 Power cycle transceiver under test
2 Connect CW signal as stated above via GPS RF connector
3 Connect DAU-9T cable to Tomahawk connector
4 On Phoenix, choose connection as FBUS and select File/Scan Product
5 Select Troubleshooting/GPS Testing/GPS Quick Test/Test Mode Galvanic
in Phoenix
Page 18
Figure 11: GPS Component Placement (PWB top side)
Nokia Corporation
CCS Technical Documentation
Confidential Issue 1 02/2003