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eritelecom
2011-10-15, 12:15 AM
Hi Friends,

We are performing some automatic drive tests using SwissQual tool.
I noted that in many measurements we have RxQualFull = 4 and RxQualSub = 0 though DTX not activated (DTX = False) !!
Could anyone give me a simple explanation for this behavior ?
u find attached a screenshot for the radio parameter.
Thanks inn advance for ur collaboration.

Regards

echomoon
2011-10-15, 04:56 AM
In GSM , there r 2 types of valuse presented for RXQual,namely RXQual_full and RXQual_sub.
the full valuse r based upon all frames on SACCH multiframe,wether they have been transmitted from the base station or not.this means that if DTX DL has been used,the full valuse will be invalid for that period since they include bit-error measurments at periods when nothing has been sent resulting in very high BER.
intotal,100 bursts(25blocks) will be used for full valuse.
The SUB valuse r based on mandatory frames on the SACCH multifram.

so here is what u should do:
-Use SUB value when DTX enabled
-Use FULL value when DTX Disabled(Due to Higher confidence)

best regards

Runner
2011-10-15, 05:01 PM
#2 is right,i think RXQUAL_FULL is the value of sampling.

eritelecom
2011-10-17, 06:49 PM
Hi Friends,

Thank u for ur explanation, however I had this information before.
What i need to know is what happens if I use RxQualFull when DTX is enabled ?
I mean if DTX enabled, RXQualFull will not be significant for our investigation ? DTX is activated by Cell I think that I could not balance in the map between Full and Sub values according to Cell caracterisics.
Sometimes I see that RxQualSub is higher and sometimes not despite the constant values of DTX (True for example) , any explanation for this phenomena ?

thx

linhhy
2011-10-17, 11:21 PM
Hi Friends,

Thank u for ur explanation, however I had this information before.
What i need to know is what happens if I use RxQualFull when DTX is enabled ?
I mean if DTX enabled, RXQualFull will not be significant for our investigation ? DTX is activated by Cell I think that I could not balance in the map between Full and Sub values according to Cell caracterisics.
Sometimes I see that RxQualSub is higher and sometimes not despite the constant values of DTX (True for example) , any explanation for this phenomena ?

thx

Hi,

Basically RxQualFull based on measurement 100 timeslot (TS) in 1 SACCH frame, means all TS is measured and calculated. RxQualSub based on 12 fixed TS (8 SID TS + 4 SACCH TS).

For DTX network, RxQualFull isnt correct, because many silent TSs are measured and calculated --> RxQualSub is better.

For no DTX network, RxQualFull is correct. But it's not always equal to RxQualSub because of different TS what is measured and calculated.

cheers,

J_Ahmad
2011-10-19, 11:07 PM
RxQual Full measurements are performed over all timeslots of SACCH Multiframe while RxQual SUB measurements are performed over mandatory timeslots that is SID and SACCH block of 104 timeslots of SACCH multifram so its no surprise that those are different irrespective of the fact that DTX is enabled or not hence there are different values appearing in tool for both.

melkaiy
2011-10-20, 01:30 AM
for analysis we use RxQual _sub instead of full. Think of a juice.. if we want the juice we should drain the water.. juice is the sub and water is full. That's the simple analogy for it. hope it'll help.. please add repsss. thanks

rfnub
2011-10-22, 11:27 AM
so there is no need to monitor the rxqualfull during DT... can someone help me on this still noob in the world of cellular telecoms :confused:

J_Ahmad
2011-10-22, 12:31 PM
exactly no need to monitor Rxqual Full if DTX is activated!

Processor
2011-10-25, 07:11 AM
Excuse me if i'm wrong but i always thot Rx_QualFull referred to measurements on the BCCH TRX while the Rx_QualSub referred to measurements on your serving TRX.

Can someone kindly correct me if i am wrong?