Agilent Technologies 8922M, S GSM

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Making Measurements

Advanced Features

•SMSCell Broadcast - the SMS CB screen allows you to test whether the mobile

phoneis capable of correctly receiving and displaying a message sent from a base

station using the Short Message Service (SMS) Cell Broadcast protocol. This

screen can be accessed by highlighting theMore field in any main screen and

selectingSMS CB.

Using RF Rise

Triggering When using RF Rise triggering of measurements, the Trigger Delay should be

adjustedso that the wanted data is captured during the sampling process. The actual

measurement is made at the Trigger Delay time after the RF Rise. When changing

from RF Rise triggering to another trigger mode, the Trigger Delay should be

adjusted to the appropriate value as the default Trigger Delay is not automatically

restored.

Example: In the Agilent 8922M/S, when using the RF Rise, a Trig-ger Delay of 0 is recommended. When changing from RFRise to Ext Demod trigger mode, the default value of473.4T should be re-entered for Trigger Delay.The value473.4T is derived from the 468.75 bits of delaybetween downlink and uplink plus the 4.7 bits of modula-tion delay inside the Agilent 8922M/S. All timing is refer-enced to the beginning of bit zero on the downlink TCHtimeslot, (DCH or BCCH timeslot if TCH is not active.)

Effect of the RF

Generator on RF

Analyzer

Measurements

Whenthe RF Generator is set to a high level relative to the analyzer RF input, some

errormay be introduced in the analyzer’s power detector. This is due to the isolation

limits between generator and analyzer on the RF IN/OUT port. This only occurs

when the RF Generator and RF Analyzer share the RF IN/OUT port. If the

RFGenerator uses the AUX RF OUT port, no error occurs.

RFin is the amplitude in dBm of the signal into the RF IN/OUT port. Normally the

setting in dBm of the RF Analyzer Amplitude.RFgen is the setting in dBm of the

RF Generator.

Because the two components are not always in phase, the actual error will often be

slightly less.

Error 10LOG 10

RFin 20–

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

RFgen 14+

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

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RFin 20–()–dBm=