Gps Rx Chain Checking - Nokia NPD-4 Series Troubleshooting - Gps

NPD-4
Troubleshooting — GPS
3 Next connect oscilloscope 10:1 probe into J011(GPS_B0), J012(GPS_B1),
J013(GPS_B2) or J014(GPS_B3) outputs of the N001 (pins E7, F7, G7 and G6)
4 Sampled signal going to GPS BB should look like in the following picture:

GPS RX Chain Checking

1 Connect 1575.520152 MHz CW signal generator at the level of –100dBm to GSP
antenna connector. NOTE: Cable loss or attenuator loss has to be taken into
account.
2 Connect spectrum analyzer through active probe with attenuator into filter Z001
output
3 If connector/switch X001 and filter Z001 are OK, the signal level should be simi-
lar to the following picture:
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Figure 19: Sampled signal going to GPS BB
Nokia Corporation
CCS Technical Documentation
Confidential Issue 1 02/2003