Installation Instructions

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COMPANY CONFIDENTIAL CENG0336_XE_nanoBTS_Installation_and_Test_Manual.doc
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• whether it is supported on the nanoBTS unit in question
• whether it is currently available (ie. whether a clock source is present)
• whether it is currently the active clock source (ie. the one that the unit is taking
its timing from)
On nanoBTS models that are not multi-TRX capable, the Internal OCXO is always
supported, available and active, and neither TIB Clock Input nor 10 MHz Input are
supported. On other nanoBTS models, all three sources are supported.
The Status group box indicates, for the currently active clock source:
• whether GSM frame pulses are being received (these are only expected if the
active clock source is TIB Clock Input)
• whether GSM frame numbers are being received (again, only expected if the
active clock source is TIB Clock Input)
• whether the external clock input is valid (this applies only if the active clock
source is either TIB Clock Input or 10 MHz Input)
The Status group box also indicates whether timing bus output control is supported.
On nanoBTS models that are not multi-TRX capable, it is never supported. On other
nanoBTS models, it is supported on a master, but not on a slave.
The TIB Output group box contains a set of three radio buttons that allow the user to
choose between automatic, enabled and disabled. These buttons are only enabled if
timing bus output control is supported.
Clicking the spin controls (the buttons with up and down arrows) on this dialog box
adjusts the OCXO frequency up or down by 100, 10 or 1 ppb. These spin controls are
only enabled if the TIB Output is set to enabled. Each change is sent to the nanoBTS
immediately, so the user can see the effect on the nanoBTS’ frequency immediately
using the external frequency measuring equipment. When the desired frequency has
been reached press the Close button; a note of the starting and ending values of the
Frequency Control is made in the log.
A nanoBTS’s frequency can only be adjusted manually if Internal OCXO is the active
clock source. If the Internal OCXO is not the active clock source and the nanoBTS
being adjusted is a master, remove its 10 MHz input.
If the active clock source shown in the Clock Sources group box is not Internal OCXO,
BTS Installer disables the Frequency Control spin controls. However, since this display
is only refreshed by user action, it can be out of date. If the user attempts to use the
spin controls to adjust the frequency of a nanoBTS that has an active external clock
source, the nanoBTS rejects the update and BTS Installer displays an error message
indicating “resource not available” in the progress bar on the Frequency Control dialog
box.
In order to be able to monitor the frequency of a master’s TIB Out signal while making
adjustments, the user may have to change the TIB Output setting to Enabled. It is the
user’s responsibility to ensure that the TIB Output setting is restored to the previous
value (if that is what is required) when adjustment is complete. If when the user closes
the Frequency Control dialog box, the TIB Output setting is different from when the
dialog box was opened, BTS Installer displays a warning to that effect and gives the
user the option to confirm or cancel.