User Guide

Receiver troubleshooting

Introduction to Rx troubleshooting

Rx can be tested by making a phone call or in the local mode. For the local mode testing, use Phoenix service

software.

The primary Rx troubleshooting parameter RSSI (Receiving Signal Strength Indicator). For GSM RSSI

measurement, see GSM Rx chain activation for manual measurements / GSM RSSI measurement

(page 7–12), and for the same measurement in WCDMA, see WCDMA RSSI measurement (page 7–14).

In GSM, the input signal can be either a real GSM signal or a CW (Continuous Wave) signal, which is 67.771

kHz above the carrier frequency.

In WCDMA, the input signal can be either a real WCDMA signal or a CW signal, which is 1 MHz above the carrier

frequency.

For service tool usage instructions, refer to section Service Tools and Service Concepts.

Related information

• WCDMA Rx chain activation for manual measurement (page 7–13)

GSM Rx chain activation for manual measurements / GSM RSSI measurement

Context

RSSI signal measurement is the main Rx troubleshooting measurement. The test measures the strength of

the received signal.

I and Q branches can be measured separately. In GSM, the input signal can be either real GSM signal or a CW

(Continuous Wave) signal that is 67.771 kHz above the carrier frequency.

Steps

1. Start

Phoenix

service software.

2. Choose Testing→GSM→RSSI Reading .

3. Set the RF signal generator for channel frequency +67.771 kHz CW mode with –80 dBm signal.

Alternatively set the cellular tester downlink channel to the appropriate channel. Make sure that the tester

is set to continuous mode, not to burst mode.

RM-10;RM-24

Nokia Customer Care RF Troubleshooting and Manual Tuning Guide

Page 7 –12 COMPANY CONFIDENTIAL Issue 1