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khaledkhoudi
2012-02-26, 01:57 AM
Hello experts,

I need your help about these questions:

What's the difference between the NodeB Channel element and the cell channel element?
What's the parameter to use to determine if the cell is congested or not?
What's the OSVF codes ? how can we judge the code congestion in a cell ?

Thanks

agenov
2012-02-26, 06:41 AM
it depends on your vendor but in brief is like this



I need your help about these questions:

What's the difference between the NodeB Channel element and the cell channel element? - All CEs are defined per NodeB pool, of course you can have cell level consumption statistic. Generally speaking when you do comparison there shouldn't be any difference between both consumption at cell and NodeB level.
What's the parameter to use to determine if the cell is congested or not? - you may use your vendor specific counters for RRC/RAB blocking due to different causes.
What's the OSVF codes ? how can we judge the code congestion in a cell ? - http://en.wikipedia.org/wiki/Chip_(CDMA). You (http://en.wikipedia.org/wiki/Chip_(CDMA). You) may use your vendor specific counters for RRC/RAB blocking due to code congestion cause.


BR
Alex

khaledkhoudi
2012-02-26, 09:44 PM
Dear Alex

What's the practical use of the OVSF codes in 3G Network ? can you give me exemples ?

Thanks

ritgail
2012-02-27, 01:34 AM
Dear Alex

What's the practical use of the OVSF codes in 3G Network ? can you give me exemples ?

Thanks

okey, OVSF(orthogonal variable spreading factor) codes or sometimes called Wales codes are orthogonal in nature. each information bit is multiplied by this codes so that each information tunnel has its own identity...
or in case of 3G(UMTS) which is a Wideband CDMA. use these codes to differentiate the different channels.. generally it separates users in downlink.

If want more try searching code tree in UMTS in google or you will find many documents in this forum. Go for the basic material..there you will find..
http://en.wikipedia.org/wiki/Chip_(CDMA)
if you dont..i will provide just let me know..

firstmaxim
2012-02-28, 04:36 AM
Dear Alex

What's the practical use of the OVSF codes in 3G Network ? can you give me exemples ?

Thanks

OVSF codes are used to spread the narrow band user data, to a wideband signal. A wideband signal has a better performance, in the face of frequency selective fading. Another function, which is achieved is orthogonality between the different services, so that different users/services can share the same 5 MHz band over the air interface.