EXPRESS DAS
Installation and Operations Manual
EXPRESS DAS Installation and Operations Manual – Version 2.2 November 2013
119
13
Appendix – Additional Functions
This chapter describes additional functions of the EXPRESS DAS.
13.1
Shutdown Function (Tx Output Shutdown)
The DAS has an automatic shutdown function to protect the headend and remote units when normal
operating conditions cannot be maintained. For example, the DAS shuts down automatically when the
composite downlink output power exceeds the values defined as average for the device for more than five
seconds. This time period can be adjusted in the management software.
After automatic shutdown, the DAS may automatically restart in order to assess whether the temporary
condition has changed. If the condition is still detected, the DAS will shutdown again. This cycle will be
repeated five times. After the fifth time, if the condition is still detected, the DAS will shutdown
permanently.
13.2
Total Power Limit Function (Tx Output ALC)
In order to protect the HPA and prevent spurious emissions, you can set maximum output power limits.
To do this, in the management software, turn on the ALC function and set the limit level. If the output
power exceeds the defined value, the output attenuator is adjusted to bring the output power back to
within the set limits. The output attenuator’s adjustment range is 25dB max. If output power decreases,
attenuation is decreased using the AGC function to return to the initial attenuation level.
NOTE:
This material is offered “for your information.” The system software automatically performs
many of the functions described here. Others are user-defined functions already covered in the
commissioning section.
NOTE:
A permanent shutdown will produce a fault alarm and will be reported to the Network
Operating Center (NOC) through the DMS-600.
Содержание EXPRESS Single-Carrier DAS
Страница 10: ......