Rohde & Schwarz 1094.0006.50, Руководство по эксплуатации

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CTS55 Test Sequence
1094.0006.55 4.11 E-6
4.9 8th Step - Sensitivity (RxLev and RxQual)
Every GSM mobile phone is capable of measuring the power level and quality of the signals it receives.
The result of these measurements are the RxLev and the RxQual values. During testing these values
reported back to the CTS continuously by the mobile.
The sensitivity measurement consists of sending a selected power level (the sensitivity level of the
mobile type) on the speech channel to the mobile. The measured RxLev and RxQual values are
displayed on the screen.
Transmit. level
(dBm) CTS
Level tolerance
(dBm) on mobile
(wide) RXQUAL (max. value) max. bit error rate (%)
-100
set level
-105 to <-94
(1)*
5 5.2
1)* set level -5 dB ... <set level +6 dB
→
Example: level = 100 dBm, tolerance = -105 ... <-94 dBm.
The test will be concluded with "pass" if all values lie within their tolerances. The tolerances have been
given a wide range to allow for attenuation inaccuracies when using an antenna coupler.
Possible causes for "fail":
•
The actual attenuation of the RF connection does not correspond to the attenuation set on
the CTS.
4.10 9th Step - Phase/Frequency Error and Power Ramp
These are the transmitter measurements of the of the mobile.
Phase error RMS
The phase error RMS is calculated by comparing the power burst received from the telephone with the
phase characteristic of an ideal modulator. The maximum error allowed is plus 5
°
(wide tolerances).
Phase error Peak
The peak phase error is calculated by comparing the phase of the power burst received from the mobile
with the phase characteristic of an ideal modulator. The maximum error allowed is plus or minus 20
°
(wide tolerances).
Frequency error
The frequency error of the mobile is measured at this step.
Tolerances:
±
90 Hz GSM/GSM850
(wide)
±
180 Hz PCN/PCS
Power Ramp
This measurement compares the burst received from the mobile with a predefined tolerance window.