Table of Contents
Advertisement
RH-10
Troubleshooting
RX_IF_AGC PDM value and, if needed, voltage. RSSI should be within +/- 2 dB of the
actual power in dBm on the RF connector. The AGC will try to keep the same amplitude
on Batman output; therefore, if the AGC value is larger than normal, this indicates that
the AGC is compensating for loss in the chain prior to the variable gain amplifier.
After checking RSSI and AGC value, if it is still necessary to probe to pinpoint the source
of the error, use the AMPS probing tables.
TN LNA AMPS (or Cell) LowGain (or HighGain) LO (or LM, ML, MD, MH, HM,
HI)
This tuning records RxdBCtr (which is automatically adjusted to produce the same ampli-
tude on the receiver output no matter what the input is) for the receiver with the LNA in
HighGain mode, and again with the LNA in LowGain mode. For AMPS, this is done only
on the center channel. For Cell and PCS, it is done over several channels.
The result is a value of RxdBCtr.
Manual Verification: Using Phoenix, choose this tuning in the RF Tuning dialog box.
Inject a CW signal that is 10 kHz offset from the center frequency of the channel that is
being tuned. For AMPS, set the amplitude to -65 dBm. For both Cell and PCS, set the
amplitude to -95 dBm. Record RxdBCtr, which is returned from Phoenix in the lowest
field in the RF Tuning dialog box.
Troubleshooting: Check Alfred and supporting components.
Final UI Test: Rho
Rho is a measure of CDMA transmit signal quality, which encompasses other transmitter
indicators such as phase error and magnitude error. Rho is measured with the phone in a
phone call, and is read directly from the call box. Rho is measured with the sector power
= -75 dBm. If Rho fails, check the signal purity of the LOs. Check synthesizer components
and power supply decoupling.
Final UI Test: Frame Error Rate (FER)
This measurement—also made while in a phone call—measures the frame errors of the
receiver in CDMA mode. A low amplitude signal (typically at a receiver sensitivity level of
-104 dBm), is injected into the receiver, and the FER is recorded. FER is measured in per-
centage (0.5% or lower is considered passing). Failures are most often caused by excess
loss/insufficient gain in the receiver chain. Failures may also be the result of excess noise
in the receiver. Check for correct signal levels and AGC values/voltages.
Final UI Test: SINAD
SINAD (Signal-to-Noise-and-Distortion) is similar to a sensitivity/FER measurement for
CDMA, but it is used in AMPS. A low-level signal (typically at sensitivity level of -116.0
dBm) is injected into the receiver, and SINAD is read off the call box. The passing limit is
12 dB.
Page 20
Nokia Corporation
CCS Technical Documentation
Confidential
Issue 1 09/2002
Advertisement
Table of Contents
Troubleshooting
