IES-5000/5005/6000 Support Notes

IES-5000/5005/6000 Support Notes

Upstream Power Back-Off (UPBO)

What is UPBO?

Upstream Power back-of (UPBO) helps to run services over loops with different length co-located in the same cable binder (“mixed length” deployments), especially in FEXT-dominated noise environment.

Strong FEXT generated by short loops can significantly degrade the performance of long loops if UPBO is not applied. On the other hand, UPBO reduces the transmit power of short loops and thus degrades their performance as well.

PSD

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PSD

What is UPBO? f

PSD

PSD f

Enable UPBO to allow the system to adjust the transmit PSD of all lines based on a reference line length so that the PSD at the receiving end is the same.

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PSD

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PSD

 

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PSD

 

 

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All contents copyright (c) 2008 ZyXEL Communications Corporation.

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ZyXEL Communications IES-5005 IES-5000/5005/6000 Support Notes Upstream Power Back-Off UPBO, PSD f PSD f, What is UPBO?