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clearcincom
2011-11-26, 12:22 AM
Hi there,

I'm performing some tests on a GSM900 network with NSN base stations. All sites have "normal" configurations of 3 cells and no use of any kind of repeater system.
Nevertheless, I'm recording a TA=1 when I use my drive test tools right next to the BTSE or like 50m away from the tower where the antennas are installed.

Anybody any idea why the TA=1 instead of 0?

Kind regards,
Martijn

zeezzoo
2011-11-26, 09:25 AM
you should check first the mapping table between TA & Distance .
the should be a set parameters that define this relation .
maybe you will find that TA=1 is not that big distance .

dacoder
2011-11-26, 07:31 PM
you should check first the mapping table between TA & Distance .
the should be a set parameters that define this relation .
maybe you will find that TA=1 is not that big distance .

How do we check this for Huawei system?

zeezzoo
2011-11-26, 11:38 PM
How do we check this for Huawei system?

i had worked with those parameter in NSN BR9.0
I'm not sure if Huawei has some similar parameters .

clearcincom
2011-11-27, 08:05 PM
you should check first the mapping table between TA & Distance .
the should be a set parameters that define this relation .
maybe you will find that TA=1 is not that big distance .

Where can I find this mapping in NSN BR10?
I only know about the parameter TAADJ

jayk
2011-11-27, 11:53 PM
Hi there,

I'm performing some tests on a GSM900 network with NSN base stations. All sites have "normal" configurations of 3 cells and no use of any kind of repeater system.
Nevertheless, I'm recording a TA=1 when I use my drive test tools right next to the BTSE or like 50m away from the tower where the antennas are installed.

Anybody any idea why the TA=1 instead of 0?

Kind regards,
Martijn

TEMS shows TA=0 when you are near to site. You seems to camped on far away site. TA is standard so there is no different mapping tables for different vendors.

zeezzoo
2011-11-28, 10:49 PM
Where can I find this mapping in NSN BR10?
I only know about the parameter TAADJ

the parameter name in BR9.0 is TIMADVR (Time Advance Ranges) .
Below is the description for this parameter :

========================================================================================================
TIMADVR

timingAdvanceRanges
This parameter requires 7 input values which define the 8 ranges of Timing Advance TAred (Input_value1, Input_value2, .. , Input_value7);

The input_values are related to the Timing Advance (TA) and Timing
Offset (TO) of the measurement report :

TA = TO_measurement_report + TA_measurement_report

The TA value is then related to steps of 550 meters . The allowed input values for TA are 0 to 550, defined by means of "range-Bound<n>" fields (<n>=1..7) .

The correspondence between the Input_values, TA_RED and TA is the following :

TA_RED_Range0: TA<= Inputvalue1
TA_RED_Range1: Input_value1 <TA<= Inputvalue2
TA_RED_Range2: Input_value2 <TA<= Inputvalue3
TA_RED_Range3: Input_value3 <TA<= Inputvalue4
TA_RED_Range4: Input_value4 <TA<= Inputvalue5
TA_RED_Range5: Input_value5 <TA<= Inputvalue6
TA_RED_Range6: Input_value6 <TA<= Inputvalue7
TA_RED_Range7: Input_value7 <TA

Validity Range
rangeBound1 0 - 216
rangeBound2 0 - 216
rangeBound3 0 - 216
rangeBound4 0 - 216
rangeBound5 0 - 216
rangeBound6 0 - 216
rangeBound7 0 - 216

Default Value
rangeBound1 1
rangeBound2 2
rangeBound3 3
rangeBound4 4
rangeBound5 5
rangeBound6 6
rangeBound7 7
========================================================================================================

jayk
2011-11-29, 01:33 AM
the parameter name in BR9.0 is TIMADVR (Time Advance Ranges) .
Below is the description for this parameter :

========================================================================================================
TIMADVR

timingAdvanceRanges
This parameter requires 7 input values which define the 8 ranges of Timing Advance TAred (Input_value1, Input_value2, .. , Input_value7);

The input_values are related to the Timing Advance (TA) and Timing
Offset (TO) of the measurement report :

TA = TO_measurement_report + TA_measurement_report

The TA value is then related to steps of 550 meters . The allowed input values for TA are 0 to 550, defined by means of "range-Bound<n>" fields (<n>=1..7) .

The correspondence between the Input_values, TA_RED and TA is the following :

TA_RED_Range0: TA<= Inputvalue1
TA_RED_Range1: Input_value1 <TA<= Inputvalue2
TA_RED_Range2: Input_value2 <TA<= Inputvalue3
TA_RED_Range3: Input_value3 <TA<= Inputvalue4
TA_RED_Range4: Input_value4 <TA<= Inputvalue5
TA_RED_Range5: Input_value5 <TA<= Inputvalue6
TA_RED_Range6: Input_value6 <TA<= Inputvalue7
TA_RED_Range7: Input_value7 <TA

Validity Range
rangeBound1 0 - 216
rangeBound2 0 - 216
rangeBound3 0 - 216
rangeBound4 0 - 216
rangeBound5 0 - 216
rangeBound6 0 - 216
rangeBound7 0 - 216

Default Value
rangeBound1 1
rangeBound2 2
rangeBound3 3
rangeBound4 4
rangeBound5 5
rangeBound6 6
rangeBound7 7
========================================================================================================

This parameter is specifying seven ranges of TA RED based on actual measurement value of TA. Parameter seems to be used for counter pegging. It is not mentioned anywhere that actual TA values will be changed and reported to MS. TA value measurement is standard procedure in 3GPP, its not vendor specific. There is no such parameter in Huawei. I did not find TIMADVR in BR9.0 documents with me. I request you to share document here, I wanted to have a look on the feature supporting this parameters.

zeezzoo
2011-11-29, 06:26 AM
This parameter is specifying seven ranges of TA RED based on actual measurement value of TA. Parameter seems to be used for counter pegging. It is not mentioned anywhere that actual TA values will be changed and reported to MS. TA value measurement is standard procedure in 3GPP, its not vendor specific. There is no such parameter in Huawei. I did not find TIMADVR in BR9.0 documents with me. I request you to share document here, I wanted to have a look on the feature supporting this parameters.

you are right . this parameter only affects the counters not the DT .
the BR9.0 doc you want is on the below link :
http://hotfile.com/dl/136233081/873ff71/bsccml.rar.html
Password : iwanttolearn

anyone tried to attach something after upgrading the forum , I'm not able to do so if thee file size was more than 1 MB .
BR,

EngSoft
2011-11-30, 07:44 PM
Hi there,

I'm performing some tests on a GSM900 network with NSN base stations. All sites have "normal" configurations of 3 cells and no use of any kind of repeater system.
Nevertheless, I'm recording a TA=1 when I use my drive test tools right next to the BTSE or like 50m away from the tower where the antennas are installed.

Anybody any idea why the TA=1 instead of 0?

Kind regards,
Martijn

its a usual thing , you can see TA=1 even if you are at the site ( on in the shelter) its came due to the face the signal have multiple path and when calculating the TA the mulitpath is consider . so usually TA=1 and TA=0 are any thing less than 500m

mohyedeen_alkousy
2011-11-30, 10:38 PM
This Parameter TIMADVR is used in collecting statistics related to timing advance on TRX level its not used to map any distance to any TA
also TA is GSM standard 550m step so u cannot change it
if u have TA=1 near the site and you are camping on the site it means that the signal is reflected to you from some neighboring building so the signal will take longer path and give TA=1 or TA=2
also if you have synchronization problems in the site it will give u wrong TA



the parameter name in BR9.0 is TIMADVR (Time Advance Ranges) .
Below is the description for this parameter :

========================================================================================================
TIMADVR

timingAdvanceRanges
This parameter requires 7 input values which define the 8 ranges of Timing Advance TAred (Input_value1, Input_value2, .. , Input_value7);

The input_values are related to the Timing Advance (TA) and Timing
Offset (TO) of the measurement report :

TA = TO_measurement_report + TA_measurement_report

The TA value is then related to steps of 550 meters . The allowed input values for TA are 0 to 550, defined by means of "range-Bound<n>" fields (<n>=1..7) .

The correspondence between the Input_values, TA_RED and TA is the following :

TA_RED_Range0: TA<= Inputvalue1
TA_RED_Range1: Input_value1 <TA<= Inputvalue2
TA_RED_Range2: Input_value2 <TA<= Inputvalue3
TA_RED_Range3: Input_value3 <TA<= Inputvalue4
TA_RED_Range4: Input_value4 <TA<= Inputvalue5
TA_RED_Range5: Input_value5 <TA<= Inputvalue6
TA_RED_Range6: Input_value6 <TA<= Inputvalue7
TA_RED_Range7: Input_value7 <TA

Validity Range
rangeBound1 0 - 216
rangeBound2 0 - 216
rangeBound3 0 - 216
rangeBound4 0 - 216
rangeBound5 0 - 216
rangeBound6 0 - 216
rangeBound7 0 - 216

Default Value
rangeBound1 1
rangeBound2 2
rangeBound3 3
rangeBound4 4
rangeBound5 5
rangeBound6 6
rangeBound7 7
========================================================================================================