User`s guide

28
Screens
Dual Band Control Screen
5. Downlink Amplitudes
These 3 fields control the amplitudes of the downlink channels. These fields
operate differently depending on which band is being used.
E-GSM900 Band When the traffic channel is in E-GSM900 band, the GSM BCH & TCH field will
have an immediate effect. This field is identical to the RF Gen Amplitude field on
the Cell Configuration screen.
The
GSM BCH Atten. and DCS TCH fields have no effect until the traffic channel
moves to the DCS1800 band.
DCS1800 Band When the traffic channel is in the DCS1800 band, the GSM BCH & TCH field has
no effect until the traffic channel moves back to the E-GSM900 band.
The GSM BCH Atten. field controls the attenuation of the E-GSM900 BCH. The
DCS TCH field controls the amplitude of the downlink traffic channel. Both these
fields have an immediate effect.
GSM BCH Atten.
and
Nominal Ampl.
When the TCH is in the DCS1800 band, the BCH remains in the E-GSM900 band.
The amplitude of this BCH is nominally -60 dBm. This level can be changed by
introducing increasing levels of attenuation. For example, selecting
GSM BCH Atten. will reduce the BCH amplitude to -90 dBm nominal.
NOTE: Although the absolute BCH level is a typical specification, the relative changes in
amplitude are more accurate. To determine an accurate absolute level, refer to
‘Appendix A - Establishing Absolute GSM BCH Power Level’ on page 81 for
more information.
GSM BCH
& TCH
Default -85 dBm
Range -6.0 dBm to -127.0 dBm (no electronic attenuation)
-7.0 dBm to -127.0 dBm (with electronic attenuation)
GSM BCH Atten. Default 20 dB
Range 0, 10, 20, 30, 40, 50, 60, 70 dB
DCS TCH Default -85.0 dBm
Range -127.0 dBm to -12.0 dBm
30 dB