Manual operation

Making measurements

Making measurements

Once a call is established, you can make measurements as before—see the HP/Agilent 8922 User’s Guide for more details. Note however that there are two new factors which you need to consider: choosing which timeslot to perform measurements on, and performing BER on the two- unit system.

Choosing which timeslot to measure

Any HSCSD instrument can measure the master or the slave timeslot. This selection is made on the HSCSD control screen, and the measurements on this screen include a reminder of which slot is currently being analysed. On other screens, where this reminder is not present, you must be aware of which slot you are measuring.

Measuring BER

To perform BER, one instrument starts a measurement, while the other makes the measurement. Specifically, to perform BER on the slave timeslot, you must start the BER measurement on the master unit because it is the master unit which performs the signalling to place the mobile in loopback mode. Once this is done, the BER measurement must be started on the slave unit, where it will then run as normal. After the measurement is complete, and the master unit is returned to a different screen, the HP/Agilent 8922 signals the mobile and takes it back out of loopback mode.

Changing band and making measurements in the E-GSM900 and DCS 1800 bands

Changing band and making measurements in the E-GSM900 and DCS1800 bands are performed in the same way as for the HP/Agilent 8922 Multi-Band System. See the HP/Agilent8922 Multi-Band Test System Supplementary User’s Guide for details.

Chapter 3

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Agilent Technologies 8922 P manual Making measurements, Choosing which timeslot to measure, Measuring BER