TMD B9pres 11Oct05 CS Aspect Ed02

7/28/2019 TMD B9pres 11Oct05 CS Aspect Ed02

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All rights reserved 2005, Alcatel

B9 Parameter WorkshopPart 1: Circuit Switched (CS) Aspects

Presentation to T-Mobile, Bonn, 11 Oct 2005

Alcatel-PCS


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All rights reserved 2005, AlcatelTMD_B9_pres_CSpart / Oct 05

Page 2

Agenda

B9 features and related parameters:

Enhanced E-GSM band handling

Electromagnetic environment (EME) supervision

Radio Measurement Statistics (RMS) improvements

Voice Group Call Services (VGCS)

Features influencing the B9 channel allocation strategy forCS calls:



Intracell HO cause 30


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Enhanced E-GSM band handlingIntroduction (1/2)

Feature goals in B9: full support of the (E)GPRS service on the E-GSM TRXs of an E-GSM cell

signaling in G1 band

Limitations in B7.2 and B8: (E)GPRS service is not supported on G1 TRXs;

Signaling is not supported on G1 TRXs;

Only one GPRS MA;

The frequency hopping shall be applied only to a set of G1 frequencies or toa set of P-GSM frequencies.

Band ARFCNUplink Freq.

(MHz)Downlink Freq.

(MHz)

P-GSM 1 .. 124 890.2 to 915.0 935.2 to 960.0

G1-GSM 975 .. 1023, 0 880.2 to 890.0 925.2 to 935.0

G1-GSM

band

E-GSM uplink

E-GSM downlink

P-GSM band

G1-GSM

bandP-GSM band

880 890 915

935925 960


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Enhanced E-GSM band handlingIntroduction (2/2)

Characteristics of E-GSM in B9:The (E)GPRS service is supported, without any constraint, on E-GSM

TRXs;

Mixing frequencies of P-GSM band and G1 band in the same FHS issupported.

For Business cases 2, 3: all types of signaling channels (BCCH,CCCH, MPDCH, etc) are supported, without any constraint, on E-GSM TRXs;

For Business cases 1 only: the radio resource allocation strategyapplied for P-GSM capable only MSs is different than that applied forE-GSM capable MSs

Expected gains in B9Additional network capacityDecrease of the interference level in the P-GSM band by unloading

the P-GSM TRXs


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Enhanced E-GSM band handlingMarket View

Business Case 1: P-GSM network extension with the frequencies inG1 band

The operator has mainly the frequency in the P-GSM band. Some frequencies in G1

band are added to the cells for capacity extension purpose.

In this Business Case, the old Phase 1 MS may still be in use in the network.

In this presentation the Phase 1 MS is named as P-GSM capable only MS.

Business Case 2: DCS 1800 network extension with the frequencies in

E-GSM band (without frequencies in the P-GSM band)

In this Business Case, all MSs used are at least Phase 2 MSs, as a consequence, they

can decode G1 frequencies.

Business Case 3: : Full G1 network (without any frequency in the P-GSM band) or network with mainly the frequencies in G1 band

In this Business Case, all MSs used are at least Phase 2 MSs, as a consequence, they

can decode G1 frequencies.


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Enhanced E-GSM band handlingFunctional description (1/3)

The Enhanced E-GSM band handling" feature can work intwo different modes :

Mode 1 : P-GSM capable only MSs are not supported

The mode 1 covers the Business Case 2 and 3.

The allocation algorithm is linked to EGSM_RR_ALLOC_STRATEGY parameter set to

Same behaviour for E-GSM capable MS (1)

Mode 2 : P-GSM capable only MS are supported

The mode 2 covers the Business Case 1.

The allocation algorithm is linked to EGSM_RR_ALLOC_STRATEGY parameter setto Different behaviour for E-GSM capable MS (0)

The parameterEGSM_RR_ALLOC_STRATEGY is notmodifiable at the OMC-R : to be set in the BSC CDE Table


7/81All rights reserved 2005, AlcatelTMD_B9_pres_CSpart / Oct 05

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Mode 1: Support of E-GSM networks With this mode :

the E-GSM TRX is defined as follow:

frequencies in P-GSM band only

or frequencies in G1 band only

or mixing frequencies in P-GSM band and G1 band.

The (E)GPRS service is supported, without any constraint, on E-GSM TRXs.

All types of signaling channels (BCCH, CCCH, MPDCH, ) are supported, without any constraint,on E-GSM TRXs.

Resource allocation strategy:

As the P-GSM capable only MS is not supported, there is not specific radio resource allocation

strategy in the E-GSM cell. In particular, P-GSM capable only MS is not ensured to be allocated with P-GSM resources

G1 P-GSM

E-GSM

880 890 915

925 935 960

G1 P-GSM


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Mode 2: Support ofP-GSM only MS in E-GSM networks

The main characteristics of this mode is as follows :

The radio resource allocation strategy applied forP-GSM capable only MSs is

different than that applied forE-GSM capable MSs.

From the radio resource allocation point of view, the meaning of E-GSM TRX is

changed. An E-GSM TRX is re-defined as follow:

frequencies in G1 band only

or mixing frequencies in P-GSM band and G1 band.

BCCH, CCCH, SDCCH and CBCH cannot be defined on E-GSM TRX

E-GPRS services can be supported on E-GSM TRX

The new radio resource allocation strategy is based on the hypotheses that all

GSM900 (E)GPRS MSs are assumed E-GSM capable and compliant to Phase 2 of

3GPP standard.


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Enhanced E-GSM band handlingOMC-R parameters (1/2)

HMI name Definition Sub-system

Instance

OMC-Raccess

Type Defvalue

Range Unit

EGSM_RR_ALLOC_STRATEGY

Defines the radio resourceallocation strategy used in E-GSM cells.

0: Different behavior for E-GSMcapable MS: The BSS handlesdifferently E-GSM capable MS fromP-GSM only capable MS in E-GSMcells.

1: Same behavior forE-GSM

capable MS: The BSS handles inthe same way only P-GSM capableMS as E-GSM capable MS in E-GSM cells,

BSC BSS Displayed Number 0 [0,1] None


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Enhanced E-GSM band handlingOMC-R parameters (2/2)


Instance

OMC-Raccess

Type Defvalue

Range Unit

FREQUENCY_RANGE This parameter indicates thefrequency range of the cell.

0: PGSM (GSM 900),

1: DCS 1800,

2: EGSM,

3: DCS 1900,

4: PGSM-DCS1800,

5: EGSM-DCS1800,

6: GSM 850

BSC cell Changeable

Number 0 [0,6] None

PLMN_FREQUENCY_BANDS (BSC)

Frequency bands used inthe whole PLMN.

BSC BSS Virtualchangeable

Number 0 [0,3] None

PLMN_FREQUENCY_BANDS (MFS)

Frequency bands used inthe whole PLMN.

MFS BSS Virtualchangeable

Number 0 [0,3] None

HMI name Definition Sub-

system

Insta

nce

OMC-R

access

Type Def

value

Range Unit

EN_LOAD_EGSM Allows to take into account TCHresources of G1 TRXs for loadevaluation. When enabled, thevalues of the parametersFREElevel_1 to FREElevel_4need to be updated to numberof TRX considered in the loadcomputation.

BSC BSC changeable Flag 1 [0,1] None


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Agenda




Radio Measurement Statistics (RMS) improvementsVoice Group Call Services (VGCS)






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EME supervisionIntroduction (1/3)

Feature goals in B9:

detect situations where the emitted power is exceeding the maximumvalue pre-defined at commissioning per cell and per frequency band

record over time the average power emitted at the BTS antenna output

connector per cell and per frequency band (i.e. power evolution overtime for each cell and per band)

with the help of appropriate tools (e.g. A956 RNO) to:

provide warning report on the delta power between the average emittedpower per cell and per band (EME_PWR_GSM resp. EME_PWR_DCS) and apredefined threshold (EME_PWR_MAX_GSM resp. EME_PWR_MAX_DCS)

display evolution of EME_PWR_GSM and EME_PWR_DCS

display the absolute BCCH power at the BTS antenna output connector

provide statistics and tendencies on the emitted power for each cell (perband).


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Limitations in B8:

no information on the emitted power of the cell

Expected gains in B9:

secure the application of regulatory requirements

anticipate situations that may imply a revision of the accessrestrictions

collect raw data on the actual levels of emitted power

collect more accurate values at the BTS level taking into accountpower control and DTX

support dialogue with neighborhood and local authorities on sensitivesites with daily statistics


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EME i i


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EME supervisionFunctional description (1/4)

Characteristics of EME supervision feature in B9:

1.) new BSS PM type is defined for EME: Type 33

restriction in the PMC configuration (for the EME type only) :

start-time value is forced to 00:00 and stop-time value is forced to 24:00 (interm of OMC local time)

accumulation period is blocked to 1 hour

Storage of hourly indicators: during 1 month

Storage of daily maximum power indicators: during 13 months

EME i i


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2.) PM33 type data collection (description)

The mechanism is permanent in EVOLIUM TRE and between BSC/TCU andEVOLIUM BTS/TRE; it involves all EVOLIUM TREs and all TCUs connected to1 or more EVOLIUM TREs:

every EVOLIUM TRE collects DL power data

every TCU sends every 15 minutes (and in the same time) the messageEME_DATA_REQ to all EVOLIUM TRE connected to it.

after sending EME_DATA_REQ to a TRE, BSC/TCU starts a wait timer(EME_DATA_TIMER) to wait the EME_DATA_IND from this TRE.

after reception of the message EME_DATA_REQ, each EVOLIUM TRE resetscounters, prepares statistics and sends EME counters to the related TCU inthe message EME_DATA_IND.

if no EME_DATA_IND received from a given TRE by TCU before time out, the h counter value will be set to invalid.

if EME_DATA_IND is delayed i.e. received by BSC after time out, the countervalue is discarded by the BSC

EME i i


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2.) continued: PM33 type data collection (visualisation of EMEmessage flow between BSC and BTS)

EME i i


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3.) Calculation of TRX average power at the antenna connector (ANoutput) takes into account:

Static power contribution:

TRE maximum power

power leveling

loss due to stages (ANy, AN) and cables between TRE output and BTSantenna output connector

BS_TXPWR_MAX

Dynamic power contribution: Power control

No power

contribution: DTX

unused timeslots

EME i i


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EME supervisionOMC-R parameters


Instance

OMC-Raccess

Type Defvalue

Range Unit

EME_PWR_MAX_

GSM

= operationalparameters (no impacton the telecom part, buton O&M).

This threshold is themaximum power level than aBTS (cell) is permitted toemit at the BTS antennaoutput connector on theGSM bands (850 MHz and900 MHz). It is set accordingto the size of thecompliance boundary, i.e.the wider the complianceboundary, the higher thethreshold value can be.If thepower level exceeds thisthreshold, then there is somechance that the referencelevels are no morerespected beyond thecompliance boundary.

OMC cell changeable Threshold

9999 [1,9999]

None

EME_PWR_MAX_DCS

Same definition as abovebut for DCS bands(1800MHz and 1900MHz)

OMC cell changeable Threshold 9999 [1,9999] None

EME_DATA_TIMER Supervision timer for thereception of theEME_DATA_IND messageby the BSC

BSC BSC changeable timer 6 [0,255]

sec


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Agenda






Enhanced E-GSM band handlingVoice Group Call Services (VGCS)


RMS i t


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RMS improvementsIntroduction (1/2)

The B9 feature RMS improvements is composed of 3 sub-features.

Feature goals in B9:RMS improvements on AMR statistics (sub-feature RMS_I1, split into

the sub-features RMS_I12 and RMS_I13):providing measurement of AMR codec usage in RMS, for optimisation ofspeech quality through AMR

RMS improvements on TA statistics (sub-feature RMS_I2):providing statistic on RMS Timing advance, for optimisation of NWplanning, through identification of resurgences and hot spots

RMS improvements on TRX power statistics (sub-feature RFD55/138315 RMS indicators storage enhancement):providing the maximum GMSK power used by each TRE at BTSantenna connector

RMS i t


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RMS improvementsIntroduction (2/2)

Limitations in B8, B7.2:RMS on AMR (sub-feature RMS_I1): not supported in B7.2/B8

RMS on TA (sub-feature RMS_I2): only measurement reportstrespassing a TA threshold are available (counter name

PERC_TA_GT_TA_STAT), along with the max. measured TA (countername MAX_TA)

RMS on TRX power: not supported in B7.2/B8

Expected gains in B9:monitoring the proper operation of AMR and the voice quality in a cell

=> help tuning the AMR parameters (definition of the codec subset,thresholds and hysteresis)

monitoring the quality of the radio coverage and the geographical trafficdistribution in a cell (identifying hot spot and resurgences/interferencespots)

knowing the exact GMSK power of each TRE

RMS improvements


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RMS improvementsFunctional description (1/4)

General process for RMS (reminder): The BTS collects the RMS measurement results, formats them into

matrixes or vectors, and sends them to the BSC. The BSC forwards themto the OMC using the usual PM mechanism

Characteristics ofRMS improvements

feature in B9:

1.) RMS improvements on AMR statistics (sub-feature RMS_I1)

1.1) RMS_I12: Bad Frame Indication per AMR codec in UL

First, following 2 vectors are filled by each TRE of the BTS:

AMR FR UL BFI vector (TRX based)

AMR HR UL BFI vector (TRX based)

Next, for each vector listed above, there are 2 counters filled for RMSmeasurement reporting:

one counter contains the coded measurement values

the other counter contains the maximum value of all measurement values inthe vector

RMS improvements


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1.2) RMS_I13: AMR codec usage compared to RXLEV

First, following 4 matrices are filled by each TRE of the BTS:

AMR FR UL usage / UL_RXLEV (TRX based)

AMR HR UL usage / UL_RXLEV (TRX based)

AMR FR DL usage / DL_RXLEV (TRX based)AMR HR DL usage / DL_RXLEV (TRX based)

Next, for each matrix listed above, there are 2 counters filled for RMSmeasurement reporting:

one counter contains the coded measurement values,

the other counter is a vector which contains the maximum values in

each matrix row

RMS improvements


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2.) RMS improvements on TA statistics (sub-feature RMS_I2)

There are 3 groups of RMS improvements on TA statistics:

2.1)Timing advance distribution (TRX based)

2 counters are filled (TRX based):

one counter contains the coded measurement values for Timing advance

distribution per TA band the other counter contains the maximum value of all measurement value

2.2)Average Rxlev per TA band

2 counters are filled:

one with the coded measurement values for UL average Rxlev per TA band

the other with the coded measurement values for DL average Rxlev per TA band

2.3)Average Rxqual per TA band

2 counters are filled:

one with the coded measurement values for UL average Rxqual per TA band

the other with the coded measurement values for DL average Rxqual per TAband

RMS improvements


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3.) RMS improvements on TRX power statistics

One new counter (RMSpw3, TRX based) is defined, to get the maximumGMSK TRX power level applied at the BTS antenna output connector indBm.

The power takes into account the different BTS internal losses (cables,internal combiners) and the internal/ external leveling but it does not takeinto account the BS_TXPWR_MAX, attenuation required by the OMC_R.

RMS improvements


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RMS improvementsOMC-R parameters (1/2)

There are no new B9 parameters related to the sub-features:

RMS improvements on AMR statistics (sub-features RMS_I12 andRMS_I13)

RMS improvements on TRX power statistics

There are new B9 parameters related to the sub-feature:

RMS improvements on TA statistics (sub-feature RMS_I2)

RMS improvements


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RMS improvementsOMC-R parameters (2/2)


system

Insta

nce

OMC-R

access

Type Def

value

Range Unit

MEAS_STAT_TA_1 Upper limit of the first TAband, lower limit of thesecond TA band (for theRMS TA measurements)

BSC BSS Changeable

number 7 [1, 62] bper

MEAS_STAT_TA_2 Upper limit of the 2nd TAband, lower limit of the 3rdTA band

BSC BSS Changeable


MEAS_STAT_TA_3 BSC BSS Changeable








MEAS_STAT_TA_7 BSC BSS Changeabl

e




MEAS_STAT_TA_9 Upper limit of the 9th TAband, lower limit of the 10thTA band

BSC BSS Changeable


RMS improvements


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RMS improvementsRMS indicators (1/2)

Ref. name Mnemonic Definition Formula

RMAMUFBV RMS_AMR_FR_UL_BAD Number of bad speech frames using any

AMR FR codec in uplink

RMS44

RMAMUHBV RMS_AMR_HR_UL_BAD Number of bad speech frames using anyAMR HR codec in uplink

RMS45

RMAMUFSM RMS_AMR_FR_UL_RXLEV_UL Number of speech frames using oneAMR FR codec in uplink per Rxlev on

the uplink path

RMS46

RMAMUHSM RMS_AMR_HR_UL_RXLEV_UL Number of speech frames using oneAMR HR codec in uplink per Rxlev on

the uplink path

RMS48

RMAMDFSM RMS_AMR_FR_DL_RXLEV_UL Number of speech frames using oneAMR FR codec in downlink per Rxlev on

the downlink path

RMS47

RMAMDHSM RMS_AMR_HR_DL_RXLEV_UL Number of speech frames using oneAMR HR codec in downlink per Rxlev on

the downlink path

RMS49

As standards RMS indicators they are not agregatedday/week/month. They all are defined at TRX level andagregated on cell only

RMS improvements


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RMS improvementsRMS indicators (2/2)

Ref. name Mnemonic Definition Formula

RMAXTAV RMS_RXLEVEL_TA_THRESHOLD

10 TA bands: 9 thresholds + min + max TAB_PAR_MEAS_STAT__TA + min + max

RMTADIV RMS_TPR_TIMING_ADVANCE The distribution of number ofmeasurement reports for which the valueof timing advance is in TA band

RMS50

RMTAULVV RMS_TPR_UL_RXLEV_TA_BAND

The average value of RXLEV per TAband in uplink.

RMS51

RMTADLVV RMS_TPR_DL_RXLEV_TA_BAND The average value of RXLEV per TAband in downlink. RMS52

RMTAUQUV RMS_TPR_UL_RXQUAL_TA_BAND

The average value of RXQUAL per TAband in uplink.

RMS53

RMTADQUV RMS_TPR_DL_RXQUAL_TA_BAND

The average value of RXQUAL per TAband in downlink

RMS54

RMTIBPWMN MAX_POWER_PER_TRX Maximum GMSK TRX power level

applied at the BTS antenna outputconnector in dBm.

The power takes into account thedifferent losses (cables, internalcombiners) and the internal/externalleveling but it does not take into accountthe BS-TXPWR-MAX, attenuationrequired by the OMC_R..

RMSPw3


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Agenda









VGCS


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VGCSIntroduction (1/2) - ASCI overview

Advanced Speech Call Items (ASCI) are defined as additionalsupplementary services by GSM Phase 2+

ASCI features provide voice group and priority functionality

1.) Voice group services:

Voice Broadcast Service (VBS) - not implemented in B9

Typical trunked radio communication, point to multipoint, 1 speaker (MOC or MTC), manylistener.

Voice Group Call Services (VGCS) - implemented in B9 as a pure SW feature

Typical trunked radio communication, point to multipoint, several dispatcher (MOC or MTC),many listener, subsequent talker.

2.) enhanced Multi-Level Precedence and Pre-emption service (eMLPP): Precedence involves assigning a priority level to a call in combination with fast call set-up.

Pre-emption involves the seizing of resources, which are in use by a call of a lowerprecedence, by a higher level precedence call in the absence of idle resources. Pre-emption can also involve the disconnection of an on-going call of lower precedence toaccept an incoming call of higher precedence

VGCS


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VGCSIntroduction (2/2)- General concept of VGCS usage

BTS BSC

BTS

BSC

BTS

BTS BSC

Group callarea A

GMSC

Relay MSC

Distribution function

Anchor MSC

Conference bridge

Group callarea B

Group ID 1

Group ID 1

Group ID 1

Group ID 2

Group ID 2

External dispatchera

VGCS I:

Group call area A

Group ID 1

Dispatcher (external)a

One broadcast channel percell and per group call

One VGCH channel (TCH/SACCH/FACCH)may be allocated per cell and group calll

GCR

Group Call Register (GCR)

contains group call related data:

- Group ID

- Priority (network, subscriber)

- Call setup class (fast, normal)

Group ID 1

New calling subscriber (first period dedicated

channel)

VGCS


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VGCSOverview VGCS procedure involved O&M parameter

VGCS Procedure Name of involved new B9 parameters

Notification for mobile stations in idle mode NOTIF_PCH_THR

Notifications for mobile stations in GroupReceive Mode or (Dedicated) Group TransmitMode

EN_INBAND_NOTIF

NOTIF_FACCH_OTHER_VGCS_CALL_THR

Notifications for mobile stations in DedicatedMode

EN_INBAND_NOTIF

NOTIF_FACCH_PTP_CALL_THR

Paging into on-going VGCS call EN_INBAND_PAGING

INBAND_PAGING_THR

Notification Response Procedure T_NOTIF_RESPONSE_DELAY

Uplink Access Procedure T3115

NY2

Uplink Allocation Procedure (SubsequentTalker Procedure)

T_WAIT_UPLINK_REQUEST_ACK

Uplink Reply Procedure (listener detection) START_UPLINK_REPLY

T_REPETITION_UPLINK_FREE

T_WAIT_UPLINK_ACCESS

WAIT_UPLINK_ACCESS

The VGCS Call Termination Procedures(when VGCS call is released by the callingsubscriber)

T_REPETITION_CHANNEL_RELEASE

VGCS


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VGCSOMC-R parameters (1/6)


system

Insta

nce

OMC-R

access

Type Def

value

Range Unit

CS_VGCS_CHAR(0,n) This parameter allows tocharacterise an handoveradjacency, meaning to beused as for normal CircuitSwitched transaction only, orfor VGCS call only, or forboth.

BSC adj virtualchangeable

number 2 [0, 2] none

EN_INBAND_NOTIF Flag to disable/enable the in-band notification

BSC BSC changeable flag 0 [0, 1] none

EN_INBAND_PAGING Flag to disable/enable the in-band paging


EN_UPLINK_REPLY Flag to disable/enableuplink reply procedure


EN_VGCS Flag to disable or enableVGCS in the cell

BSC cell changeable flag 0 [0, 1] none

VGCS


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system

Insta

nce

OMC-R

access

Type Def

value

Range Unit

INBAND_PAGING_

THR

If the eMLPP priorityincluded in the Pagingmessage from the MSC ishigher than or equal to thisparameter, then the BSSshall trigger in-band pagingwithin cells, that areidentified to be paged fromthe PAGING message, and

that have existing VGCactive.

BSC cell changeable threshold

4 [0, 7] none

MAX_VGCS_TS Maximum number of radiotimeslots that can be usedby the VGCS calls in thecell.

BSC cell changeable number 0 [0,127]

none

MIN_VGCS_TS Minimum number of radiotimeslots that are reservedfor the VGCS calls in the cellin normal situation (point-to-

point CS call can NOT usethese timeslots).

BSC cell changeable number 0 [0, 31] none

NOTIF_FACCH_OTHER_VGCS_CALL_THR

If the eMLPP priority ishigher than or equal to thisparameter, the Notificationsmessage shall be sent onFACCH of all other on-goingVGCS call.


0 [0, 7] none

VGCS


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Instance

OMC-Raccess

Type Defvalue

Range Unit

NOTIF_FACCH_PTP_

CALL_THR

If the eMLPP priority ishigher than or equal to thisparameter, the Notificationsmessage shall be sent onFACCH of all on-going pointto point call whose MS isVGCS capable.


0 [0, 7] none

NOTIF_PCH_THR The priority threshold fornotification over PCH. The

BSS shall consider, forNotification/PCH, onlyVGCS-Calls which have apriority (eMLPP priority) notbelow this parameter. Ifmore than one is selected,all these voice group callsshall be notified on PCH andall with the same frequencyof occurrence.


0 [0, 7] none

NUMBER_NCH_

BLOCKS

This parameter defines the

maximum number of blocksusable for NCH.

BSC cell changeable number 2 [1,7] none

NY2 Maximum number ofrepetitions for the VGCSUPLINK GRANT messageduring an uplink accessprocedure

BSC cell changeable number 3 [1,7] none

VGCS


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Instance

OMC-Raccess

Type Defvalue

Range Unit

START_UPLINK_REPLY

Maximum number ofrepetitions for the UPLINKFREE message (with theUplink Access Request bitset to L) during the initial partof the uplink accessprocedure (i.e. beforesending the first UPLINKFREE message with theUplink Access Request bit

set to H)

BSC cell changeable number 256 [1,1024]

none

T14 Maximum queuing time forthe VGCS AssignmentRequests

BSC BSC changeable Timer 6 [1,19] sec

T3115 This timer is used for therepetition of the VGCSUPLINK GRANT messageduring the uplink accessprocedure.

BSC cell changeable Timer 200 [100,480]

msec

VGCS


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Instance

OMC-Raccess

Type Defvalue

Range Unit

T_NOTIF_RESPONSE_

DELAY

Timer to delay the MultipleSACCH Info Modify and theVGCS_ADD_INFO to givethe MS a chance to receivethe immediately transmittedVGCS_ADD_INFO/FACCHand SI 6 messages

BSC BSC changeable Timer 200 [100,1000]

ms

T_REPETITION_

CHANNEL_RELEASE

This parameter defines therepetition period ofCHANNEL RELEASEmessage sent on FACCH


ms

T_REPETITION_UPLINK_FREE

The UPLINK FREEmessages shall be repeatedas long as no uplink isgranted to a mobile station.This parameter defines therepetition period.


ms

T_WAIT_UPLINK_

ACCESS

Guard timer to wait forUplink Access. If no uplinkaccess bursts are receivedat this timer expiry, the BSCreleases (if EN_Uplink_Reply is set to enabled) thevoice group call channel inthat cell and then providesnotifications containing nochannel description.


sec

VGCS


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Instance

OMC-Raccess

Type Defvalu

e

Range Unit

T_WAIT_UPLINK_REQUEST_ACK

Guard timer to wait forUPLINK REQUEST ACK orUPLINK REQUESTREJECT message from theMSC.


sec

VGCS_FIX_AMR_HR_CODEC

The type AMR-HR codecused in the network

BSC BSC changeable number 2 [0,3] nonoe

VGCS_FIX_AMR_FR_

CODEC

The type AMR-FR codec

used in the network.

BSC BSC changeable number 1 [0,7] nono

e

WAIT_UPLINK_ACCESS

Maximum number ofrepetitions for the UPLINKFREE message (with theUplink Access Request bitset to L) per cycle, during thenon-initial part of the uplinkaccess procedure (i.e. aftersending the first UPLINKFREE message with theUplink Access Request bitset to H). Each time thevalue of this counterbecomes zero, the BTSsend one UPLINK FREEmessage with the UplinkAccess Request bit set to H.


VGCS


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VGCSOther parameters


Instance

OMC-Raccess

Type Defvalu

e

Range Unit

N201_BTER_D Length of information fieldon FACCH (Format Bter)

BTS BTS None (notin DLS)

number 23 [23,23] bytes

N201_BTER_S Length of information fieldon SACCH (Format Bter)

BTS BTS None (notin DLS)

number 21 [21,21] bytes

VGCS


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VGCSBSC counters (1/2)

New PM type VGCS (type 34); measured object=cellcounter

Mnemonic Definition

V01 NB_PTP_CALL_PREEMPTED_VGCS

Number of CS-calls (point-to-point) pre-empted for VGC-

Channels per cell duringobservation period

V021 AV_PARALLEL_TCH_VGCS Average number of parallel TCHin use for VGCS per cell duringobservation period

V022 MAX_PARALLEL_TCH_VGCS

Maximum number of parallelTCH in use for VGCS per cellduring observation period

V03 NB_VGC_ATTEMPTS_VGCS

Number of VGC establishmentattempts per cell duringobservation period

V04 NB_VGC_SUCCESS_VGCS

Number of VGC successfullyestablished VGC per cell duringobservation period

V05 NB_CM_SERV_REQ_VGCS

Number of receivedCM_SERV_REQ for VGC percell during observation period

V06 NB_VGC_RELEASED_VGCS

Number of released VGC percell during observation period

counter

Mnemonic Definition

V07 NB_HO_ATTEMPTS_VGCS

Number of handover attemptsfor VGC-talker per cell duringobservation period

V08 NB_HO_SUCCESS_VGCS

Number of successful handoverfor VGC-talker per cell during

observation period

V09 NB_INCOMMING_HO_VGCS

Number of incoming handoverfor VGC-talker per cell duringobservation period

V10 NB_OUTGOING_HO_VGCS

Number of outgoing handoverfor VGC-talker per cell duringobservation period

V11 NB_TALKER_CHANGE_VGCS

Number of talker change perestablished VGC in this BSS

during observation periodV12 NB_VGC_BLOCKE

D_VGCSNumber of blocked VGC due tolack of resources per cell duringobservation period

V13 NB_VGCS_NOTIFIFICATION_FACCH

Number of VGC notificationssent over FACCH per cell,differentiated for paging andnotification for VGCS.

VGCS


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VGCSBSC counters (2/2)

New PM type VGCS (type 34); measured object=cellcounter

Mnemonic Definition

V14 NB_ASS_REQ_ABLE_PREEMT_VGCS

Number ofASSIGNMENT_REQUEST ableto pre-empt per cell duringobservation period.Note: The existing counter

NB_TCH_NOR_ASS_HO_REQ_ABLE_TO_PREMPT can notbe used. As a consequence,new counter is needed: only theAssignment Request for thetalker (contains the Talker Flag)message will be counted.

V15 NB_VGCS_ASS_REQ_ABLE_PREEMPT

Number ofVBS/VGCS_ASSIGNMENT_REQUEST able to pre-empt per cellduring observation period

V16 NB_VGCS_QUEUED

VGCs queuing

V17 NB_VGCS_ESTABLISHED

Number of VGCs establishedper cell

A d


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Agenda









B9 channel allocation strategy for CS calls


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B9 channel allocation strategy for CS callsInfluence ofEnhanced E-GSM band handling (1/4)

Radio Resource allocation strategyCS allocation for E-GSM capable MS

1.Firstly select a radio timeslot which is E-GSM capable but NOT PS capable;

2.Secondly select a radio timeslot which is neither E-GSM capable nor PS capable;

3.Thirdly select a radio timeslot which is NOT E-GSM capable but PS capable;

4.Finally select a radio timeslot which is E-GSM capable and PS capable.

CS allocation for P-GSM capable only MS

1.Firstly select a radio timeslot which is neither E-GSM capable nor PS capable.

2.Finally select a radio timeslot which is NOT E-GSM capable but PS capable.

PS allocation

High

Low

E-GSM TRX, non-PS capable

Non E-GSM TRX, non-PS capable

Non E-GSM TRX, PS capable

E-GSM TRX, PS capable

CS allocation

High

Low

Non E-GSM TRX, non-PS capable

Non E-GSM TRX, PS capableCS allocation

High

Low



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TCH allocation criteria for PS capable TRXs(TRX_PREF_MARK =0) is as follows :

PS_PREF_BCCH_TRX (Highest priority to non-BCCH TRX ifPS_Pref_BCCH_TRX = Enable)

HW TRE capability (G3-> G4 MP-> G4 HP)

DR TRE capability (DR TRX ->FR TRX)

E-GSM TRX preference (new in B9, P-GSM TRX ->E-GSM TRX )

PDCH group (smallest PDCH group -> highest PDCH group)

TRX index (high TRX index -> low TRX index) TS index (high TS index -> low TS index)



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The TCH allocation criteria for non-PS capable TRXs(TRX_PREF_MARK 0) is as follows :

E-GSM TRX preference (new in B9, E-GSM TRX -> P-GSM TRX)

TRX_PREF_MARK (highest TRX_PREF_MARK -> lowestTRX_PREF_MARK)

Mobile allocation (biggest MA -> lowest MA)

Interference band (TS with best interference band-> TS with worstinterference band)

TRX index (highest index -> lowest index)

TS index (highest index -> lowest index)



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G3 - DR- P-GSM

G3 - DR- E-GSM

G3 - FR- P-GSM

G3 - FR- E-GSM

G4 - MP - DR - P-GSM

G4 - MP - DR - E-GSM

G4 - MP - FR- P-GSM

G4 - MP - FR- E-GSM

G4 - HP - DR - P-GSM

G4 - HP - DR - E-GSM

G4 - HP - FR- P-GSM

G4 - HP - FR- E-GSM

TRX with

TRX_PREF_MARK< >

0

TS 0 TS7

allocation for

CS traffic

RX's with

RX_PREF_MARK= 0

highest priority

lowest priority

allocation for

PS traffic

highest priority

lowest priority

highest prioritylowest priority

highest priority lowest priorityallocation for PS traffic

allocation for CS traffic

Agenda


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Agenda











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gyInfluence ofVGCS (1/5)

In order to have the impacts as small as possible on the currentimplemented CS and (E)GPRS radio resource management, thefollowing principles applies on the VGCS radio resource management:

1. No new radio channel type from O&M point of view: A timeslotconfigured as TCH timeslot by O&M can be used as PDCH or as

VGCS channel or standard CS TCH channel.2. The current radio resource management for CS and (E)GPRS on TRX

basis is kept.

3. No impact on (E)GPRS radio resource management: from the MFSpoint of view, there is NO difference between VGCS traffic andstandard point-to-point CS traffic.

4. The BSC CS radio resource management is modified to take intoaccount the VGCS: a timeslot configured as TCH timeslot by O&M isconsidered by the BSC as a TCH timeslot reserved for VGCS and CStraffic when it is identified neither as MPDCH timeslot nor asTCH/SPDCH/VGCH timeslot



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From BSC RAM (Radio resource allocation and Management) point of view, thefollowing types of service oriented timeslots are supported:

Pure BCCH timeslot: timeslot configured as BCC by O&M; carries common CS signalling.

Pure SDCCH timeslot: timeslot configured as a CBC or SDC by O&M; can carry SDCCHtraffic.

Pure TCH timeslot: timeslot configured as TCH by O&M; carries only TCH traffic (appliesonly to inner zone of contentric cells).

TCH/VGCH timeslot: timeslot configured as TCH by O&M; carries TCH or VGCH traffic.

TCH/SPDCH/VGCH timeslot: timeslot configured as TCH by O&M; is dynamicallyallocated as TCH or as SPDCH depending on the usage of the timeslot; can carry TCHtraffic, VGCH traffic or PS traffic.

TCH/SDCCH timeslot: configured as SDD by O&M; is dynamically allocated as TCH or asSDCCH depending on the usage of the timeslot; can carry TCH traffic or SDCCH traffic.

MPDCH timeslot: configured as TCH by O&M;can only carry common PS signalling.

From O&M side it is not possible to fix the localisation of these serviceoriented timeslots. Only the number of these timeslots can be configured.



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gyInfluence of VGCS (3/5)

GPRS

CS

GPRS/CSVGCS

VGCS/CS

VGCS/CS/GPRS

GSM 900 or DCS 1800

GSM 900GSM 900

Without VGCS

1. TRX

not installed

not installed

With VGCS

2. TRX

3. TRX

4. TRX

5. TRX

Additionalcapacityfor

VGCS

(optiona

l)

Min_PDCH

Max_PDCH

TRX_PREF_MARK=0

TRX_PREF_MARK 0 TRX_PREF_MARK 0 TRX_PREF_MARK 0

Min_VGCS_TS

Max_VGCS_TSthese TS are

point-to-

point

CS only

these TS areCS/VGCS switch-ablebut the VGCS

has priority

Legend: the colours show

the type of traffic handled

by the timeslot



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For the radio TCH allocation on TCH/VGCH timeslots (I.e.TRX_PREF_MARK0) due to a VGCS request:

=>the same principles and criteria are used as for the radio TCHallocation on TCH/VGCH timeslots due to a TCH request

For the radio TCH allocation on TCH/SPDCH/VGCHtimeslots (I.e. TRX_PREF_MARK=0) due to a VGCSrequest:

=>the same principles and criteria are used as for the radio TCHallocation on TCH/SPDCH/VGCH timeslots due to a TCH request



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Parameters in B9


Instance

OMC-Raccess

Type Defvalu

e

Range Unit

MAX_VGCS_TS Maximum number of radio

timeslots that can be usedby the VGCS calls in thecell.


MIN_VGCS_TS Minimum number of radiotimeslots that are reservedfor the VGCS calls in the cellin normal situation (point-to-point CS call can NOT usethese timeslots).




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gyOverview on next slides

The following slides show how VGCS is taken into accountby the Radio resource updating function in the Radio

Allocation and Management (RAM) process for:

the evaluation of the cell load

the evaluation of the number of TCH/SPDCH/VGCH timeslots thancan be allocated to the MFS, the substeps being:

MAX_SPDCH_LIMIT calculation

MAX_SPDCH_LIMIT TS selection

Consideration of VGCS for the PS Load


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evaluation (1/5)

The BSC takes every TCH_INFO_PERIODs a sample of the currentusage on TCH/VGCH, TCH/SDCCH and TCH/SPDCH/VGCH TS

At the expiry of the TCH_INFO_PERIOD timer, the timer is re-startedand the following load samples are calculated:

NB_USED_CS_TS(k)

NB_USED_PS_TS(k) NB_USED_VGCS_TS(k)

NB_USED_TS(k) = NB_USED_CS_TS(k) + NB_USED_PS_TS(k) +NB_USED_VGCS_TS(k)

NB_UNUSED_TS(k)

TCH_INFO_PERIOD = 5s

NB_USED_CS_TS(k)

NB_USED_PS_TS(k)

NB_USED_VGCS_TS(k)

NB_USED_TS(k)

NB_UNUSED_TS(k)



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evaluation (2/5)

NB_USED_CS_TS(k): number of available timeslots handled by the BSC andcarrying CS traffic in the cell at sampling instant tk

a TS is taken into account in the evaluation of NB_USED_CS_TS(k) if:

SPDCH allocation state = not allocated

Occupancy state = used (i.e. the TS is currently carrying CS traffic or is allocated asSDCCH)

NB_USED_PS_TS(k): number of available timeslots used for PS traffic in thecell at sampling instant tk

a TS is taken into account in the evaluation of NB_USED_PS_TS(k) if:

SPDCH allocation state = allocated or de-allocating

Occupancy state = used

NB_USED_VGCS_TS(k): number of available timeslots handled by the BSC

and carrying VGCS traffic in the cell at sampling instant tk a TS is taken into account in the evaluation of NB_USED_VGCS_TS(k) if:


Occupancy state = used



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evaluation (3/5)

NB_UNUSED_TS(k): at the expiry of TCH_INFO_PERIOD timer, theBSC computes the number of unused timeslots at sampling instant tk NB_UNUSED_TS(k) = NB_TS(k) NB_USED_CS_TS(k)

max(NB_USED_VGCS_TS(k), MIN_VGCS_TS) max(MIN_SPDCH(k),NB_USED_PS_TS(k))

NB_TS(k): total number of TCH/VGCH, TCH/SDCCH orTCH/SPDCH/VGCH timeslots available in the cell. This parameter is re-computed every RR_ALLOC_PERIOD * TCH_INFO_PERIOD to take intoaccount possible TRX failure

MIN_SPDCH(k): minimum number of SPDCHs that are always allocated tothe MFS. This parameter is re-computed every RR_ALLOC_PERIOD *TCH_INFO_PERIOD to take into account possible TRX failure

Consideration of VGCS for the PS Loadl i (4/ )


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evaluation (4/5)

Load evaluation: for each cell, every RR_ALLOC_PERIOD * TCH_INFO_PERIOD, the BSC

computes four averaged values through a sliding window of sizeLOAD_EV_PERIOD_GPRS (default value = 3):

AV_USED_CS_TS(k) =

(1/LOAD_EV_PERIOD_GPRS)*i=0 to LOAD_EV_PERIOD_GPRS -1 NB_USED_CS_TS(k-i)

AV_USED_PS_TS(k) =

(1/LOAD_EV_PERIOD_GPRS)*i=0 to LOAD_EV_PERIOD_GPRS -1 NB_USED_PS_TS(k-i)

AV_USED_VGCS_TS(k) =

(1/LOAD_EV_PERIOD_GPRS)*i=0 to LOAD_EV_PERIOD_GPRS -1 NB_USED_VGCS_TS(k-i)

AV_UNUSED_TS(k) = (1/LOAD_EV_PERIOD_GPRS)*i=0 to LOAD_EV_PERIOD_GPRS -1 NB_UNUSED_TS(k-i)

Consideration of VGCS for the PS Loadl ti (5/5)


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evaluation (5/5)

TCH_INFO_PERIOD = 5s

AV_USED_CS_TS(k)

AV_USED_PS_TS(k)

AV_USED_VGCS_TS(k)

AV_UNUSED_TS(k)

NB_USED_CS_TS(k)

NB_USED_PS_TS(k)NB_USED_VGCS_TS(k)

NB_USED_TS(k)

NB_UNUSED_TS(k)

kk-1k-2

LOAD_EV_PERIOD = 3

k+1 k+2

AV_USED_CS_TS(k+2)

AV_USED_PS_TS(k+2)

AV_USED_VGCS_TS(k+2)

AV_UNUSED_TS(k+2)

RR_ALLOC_PERIOD * TCH_INFO_PERIOD

Consideration of VGCS for theMAX SPDCH LIMIT l l ti (1/7)


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MAX_SPDCH_LIMIT calculation (1/7)

MAX_SPDCH_LIMIT calculation:

the BSC periodically (every RR_ALLOC_PERIOD *TCH_INFO_PERIOD) computes the number of Slave PDCHs that itcan provide to the MFS: MAX_SPDCH_LIMIT

MAX_SPDCH_HIGH_LOAD

Computation of CS/PS

Margin

AV_USED_CS_TSAV_USED_PS_TSAV_UNUSED_TS

NB_TS_DEFINEDNB_TS_SPDCH

Computation of

Thresholds

THR_MARGIN_PRIORITY_CSTHR_MARGIN_PRIORITY_PS

NB_TS

MARGIN_PRIORITY_CSMARGIN_PRIORITY_PS

Computation of

MAX_SPDCH_LIMIT

MAX_PDCH_HIGH_LOADMAX_PDCHMIN_PDCH

NB_TS_MPDCH

MAX_SPDCH_LIMIT

MIN_SPDCHMAX_SPDCH

O&M parameters

O&M parameter= 100 HIGH_TRAFFIC_LOAD_GPRS



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Calculation of MIN_SPDCH, MAX_SPDCH andMAX_SPDCH_HIGH_LOAD:

re-evaluated every RR_ALLOC_PERIOD * TCH_INFO_PERIOD totake into account TRX failures

introduction of a ratio named AVAILABILITY_TS_RATIO(k), evaluatedperiodically every RR_ALLOC_PERIOD * TCH_INFO_PERIOD atinstant tk:

= (NB_TS(k) MIN_VGCS_TS) / (NB_TS_DEFINED MIN_VGCS_TS)

NB_TS_DEFINED: total number of TCH/VGCH, TCH/SDCCH or

TCH/SPDCH/VGCH timeslots available in the cell if there is no TRX failure.This parameter is retrieved from the O&M configuration of the cell



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Calculation of MIN_SPDCH, MAX_SPDCH andMAX_SPDCH_HIGH_LOAD:

MAX_SPDCH(k) = RoundUp[ min(MAX_PDCH NB_TS_MPDCH,NB_TS_SPDCH) *AVAILABILITY_TS_RATIO(k) ]

NB_TS_SPDCH: total number of TCH/SPDCH/VGCH timeslots available inthe cell if there is no TRX failure. This parameter is retrieved from the O&Mconfiguration of the cell

MAX_SPDCH_HIGH_LOAD(k) = RoundUp[ min(MAX_PDCH_HIGH_LOAD NB_TS_MPDCH, NB_TS_SPDCH) *

AVAILABILITY_TS_RATIO(k) ]

MIN_SPDCH(k) = RoundUp[ (MIN_PDCH NB_TS_MPDCH) *AVAILABILITY_TS_RATIO(k) ]



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Margins for CS and PS traffics: two new margins, one for CS traffic and one for PS traffic are

introduced to guarantee that a certain number of timeslots are keptavailable for the arrival of new calls between two transmissions of theRR Allocation Indication message:

the first margin, named MARGIN_PRIORITY_CS, is dedicated to CS traffic

the second margin, named MARGIN_PRIORITY_PS, is dedicated to PStraffic

these two margins are re-evaluated every RR_ALLOC_PERIOD *TCH_INFO_PERIOD, before the computation of MAX_SPDCH_LIMIT

MARGIN_PRIORITY_CS(k) = (THR_MARGIN_PRIO_CS *(NB_TS(k) MAX_SPDCH_HIGH_LOAD(k)) / 100

MARGIN_PRIORITY_PS(k) = (THR_MARGIN_PRIO_PS *MAX_SPDCH_HIGH_LOAD(k)) / 100



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the basic idea to evaluate MAX_SPDCH_LIMIT is to estimate thenumber of unused TS and to share them between CS and PS traffic,taking into account both margins (for CS and PS traffics) defined to

guarantee a certain number of TS available to serve incoming calls

Computation of

MAX_SPDCH_LIMIT_CS

MARGIN_PRIORITY_CS

AV_USED_CS_TS(k)AV_UNUSED_TS(k)

MAX_SPDCH_LIMIT_CS(k)

Computation of

MAX_SPDCH_LIMIT_PSAV_USED_PS_TS(k)

MAX_SPDCH_LIMIT_PS(k)

MIN_SPDCHMARGIN_PRIORITY_PS

Computation of

MAX_SPDCH_LIMIT

MAX_SPDCHMAX_SPDCH_HIGH_LOAD

MAX_SPDCH_LIMIT(k)



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MAX_SPDCH_LIMIT_CS:

determines the maximum number of SPDCHs that can be allocated to the MFS inorder to ensure that a certain number of timeslots (margin) is kept in the BSC to servepossible incoming CS requests received between two sendings of the RR AllocationIndication message

MAX_SPDCH_LIMIT_CS(k) = RoundDown [ NB_TS(k) max (MIN_VGCS_TS(k) ;AV_USED_VGCS_TS(k)) AV_USED_CS(k) - MARGIN_CS(k) ]

MARGIN_CS(k) = max(MARGIN_PRIORITY_CS(k), AV_UNUSED_TS(k) / 2)

MAX_SPDCH_LIMIT_PS:

determines the minimum number of SPDCHs that should be allocated to the MFS inorder to ensure that a certain number of timeslots (margin) is kept in the MFS to

possibly serve incoming PS requests if AV_USED_PS_TS(k) is lower or equal than MIN_SPDCH then

MAX_SPDCH_LIMIT_PS(k) = MIN_SPDCH(k)

else MAX_SPDCH_LIMIT_PS(k) = RoundUp (AV_USED_PS_TS(k) +MARGIN_PRIORITY_PS(k))

Consideration of VGCS for theMAX SPDCH LIMIT calc lation (7/7)


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it can be in the range of [MIN_SPDCH, MAX_SPDCH]

its value can be either MAX_SPDCH_LIMIT_CS orMAX_SPDCH_LIMIT_PS

Zone whereMAX_SPDCH_LIMIT = MIN( MAX_SPDCH,

MAX_SPDCH_LIMIT_CS)

Zone whereMAX_SPDCH_LIMIT = MIN(MAX_SPDCH_LIMIT_PS,

MAX_SPDCH_HIGH_LOAD)

0

MAX_SPDCH

MAX_SPDCH_HIGH_LOAD

MIN_SPDCH

MIN_SPDCH

MAX_SPDCH_LIMIT_CS

MAX_SPDCH_HIGH_LOAD MAX_SPDCH

MAX_SPDCH_LIMIT_PS

Consideration of VGCS for theMAX SPDCH LIMIT TS selection (1/8)


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MAX_SPDCH_LIMIT TS selection (1/8)

PS TS and TRX ordering:

the first step consists in ordering the PS timeslots and the PS TRX soas to obtain an ordered list of TCH/SPDCH/VGCH timeslots

the ordering of the timeslots is based on the following criteria:

selection of the TRX: the TRX having the lowest rank in the TRX rankingtable (refer to the slide on TRX priority) is selected first

selection of the TS: once the TRX has been selected, theTCH/SPDCH/VGCH timeslots having the lowest timeslot index, i.e. locatedat the most left side of the TRX, is selected first



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Different PS TS zones:MAX_SPDCH_HIGH_LOAD zone:

this zone corresponds to the MAX_SPDCH_HIGH_LOAD consecutive PScapable TS that are preferred for PS allocation

in this zone, allocated TBFs cannot be pre-empted

Non pre-emptable PS zone:

this zone is always inside the MAX_SPDCH_HIGH_LOAD zone

in this latter zone, we search for the rightest TS allocated to the MFS andused. Then, all the TS located at its left define the non pre-emptable PSzone

inside this zone, a TS: remains allocated to the MFS if already allocated to the MFS

is allocated to the MFS if previously allocated to the BSC and unused

remains allocated to the BSC if already allocated to the BSC and used



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Different PS TS zones:

MAX_SPDCH_LIMIT zone:

this zone corresponds to the MAX_SPDCH_LIMIT consecutive PS capableTS that are preferred for PS allocation

inside this zone, a TS:

remains allocated to the MFS if already allocated to the MFS

is allocated to the MFS if previously allocated to the BSC and unused

remains allocated to the BSC if already allocated to the BSC and used

PS traffic zone:

this zone corresponds to the larger zone between the non pre-emptable PSzone and the MAX_SPDCH_LIMIT zone



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Different PS TS zones:

example: MAX_SPDCH_HIGH_LOAD = 8, MAX_SPDCH_LIMIT = 10

example: MAX_SPDCH_HIGH_LOAD = 8, MAX_SPDCH_LIMIT = 3

TRX2 TRX1

1 3 42 5 6 7 8 9 10 1211 13 14 15 16

MAX_SPDCH_LIMIT zone

PS CSPS CS CSCS CS

MAX_SPDCH_HIGH_LOAD zone

PS PS PS PS

Non pre-emptable PS zone

PS traffic zone

TRX2 TRX1

1 3 42 5 6 7 8 9 10 1211 13 14 15 16


PS CSPS CS CSCS CS


PS CS CS


PS traffic zone

CS



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Selection of the TCH/SPDCH/VGCH TS:

to be selected, the states of a TCH/SPDCH/VGCH timeslot must havethe following values:

SPDCH allocation state = allocated: the timeslot is already allocated to the

MFS SPDCH allocation state = not allocated and occupancy state = unused:

the timeslot is allocated to the BSC but there is no CS traffic on it



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Selection of the TCH/SPDCH/VGCH TS:

the process begins with the non pre-emptable PS zone:

all the TS in this zone that can be or are allocated to the MFS are allocated to theMFS. The verification in terms of number of TS allocated to the MFS is done onlywhen all the TS inside this zone have been handled

if at the end of the non pre-emptable PS zone, the number of selected TS forthe MFS is strictly lower than MAX_SPDCH_LIMIT then the process ofselection continues in the MAX_SPDCH_LIMIT zone

if at the end of the MAX_SPDCH_LIMIT zone, the number of selected TS forthe MFS is still lower than MAX_SPDCH_LIMIT, the process continuesoutside this zone until this number reaches MAX_SPDCH_LIMIT

once MAX_SPDCH_LIMIT TS have been selected, all the remaining

TCH/SPDCH/VGCH TS are now allocated to the BSC, even if they werepreviously allocated to the MFS. This means that a TS with a SPDCHallocation state set to allocated that is no more allocated to the MFS, has itsSPDCH allocation state set to de-allocating



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Pre-reservation mechanism in the PS traffic zone:

in order to increase the PS capacity and limit the occurrence of holesin the SPDCHs_Allocation bitmap, each TCH/SPDCH/VGCH capableTS carrying CS traffic and located inside the PS traffic zone, has its

pre-reservation state set to pre-reserved for PS. No new incomingCS call can be served on this TS, if it becomes unused once it is pre-reserved for PS. This is valid until the TS becomes not pre-reservedfor PS again and of course still handled by the BSC

the modification of the value of the pre-reservation state can onlyoccur when the SPDCHs_Allocation bitmap is built, every

TCH_INFO_PERIOD * RR_ALLOC_PERIOD seconds



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Pre-reservation mechanism in the PS traffic zone:

the following transition can be foreseen for a timeslot inside the PS trafficzone:

it goes from not pre-reserved for PS to pre-reserved for PS or remains in pre-reserved for PS if it is in one of the two following situations:

SPDCH allocation state = not allocated and occupancy state = used SPDCH allocation state = de-allocating

it goes from pre-reserved for PS to not pre-reserved for PS or remains in not pre-reserved for PS if it is in the following situation:

SPDCH allocation state = allocated

the following transition can be foreseen for a timeslot outside the PS trafficzone:

it goes from pre-reserved for PS to not pre-reserved for PS or remains in not pre-reserved for PS if it is in one of the following situations:


SPDCH allocation state = allocated

SPDCH allocation state = de-allocating

Agenda


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g









B9 channel allocation strategy for CS callsInfluence of Intracell HO cause 30 (1/4)


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Influence of Intracell HO cause 30 (1/4)

Intracell HO cause 30 =>applies for CS calls in the Non pre-emptable PSzone, independent of VGCS usage:

to speed up the release of a TS carrying a CS call inside both the non pre-emptable PS zone and the MAX_SPDCH_LIMIT zone, the concerned CS calls inthe CS zone are reallocated using an intra-cell handover (cause 30)

if EN_RETURN_CS_ZONE_HO = enabled, each time MAX_SPDCH_LIMIT iscalculated, the BSC shall check whether TCHs are allocated in both theMAX_SPDCH_LIMIT zone and the non pre-emptable PS zone.In this case, it shall send a Start HO (cause 30) message to the HO Preparationentity, to trigger an intracell handover, to move these TCHs into the CS zone

if for any reason, the handover fails, the TCH will remain in the PS zone, until thenext calculation of MAX_SPDCH_LIMIT, where a new HO could be triggered, if

still needed the TS will be considered as unused only once the handover will have been

successfully performed. As the pre-reservation state of such a TS is set to pre-reserved for PS, no new incoming CS call can be allocated on it



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This CS call is not candidate for theintra cell HO as it is outside the nonpre-emptable PS zone

TRX1

MAX_SPDCH zone

PS PSPS PS CSCS CS

TRX2


PS CS CS PS

MAX_SPDCH_LIMITzone

MIN_SPDCH zone

PS

PS traffic zone CS traffic zone

1 3 42 5 6 7 8 9 10 1211 13 14 15 16BC SD


Intra cell HO to move thisCS call to the CS traffic zone



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BCC SDC PS PS PS PS PS CS PS CS PS CS CS CS

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

TRX 1 TRX 2

MIN_SPDCH zone



MAX_SPDCH zone

non pre-emptable PS zone

PS traffic zone CS traffic zone

this call is not a candidate for HO cause 30



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Instance

OMC-Raccess

Type Defvalu

e

Range Unit

EN_RETURN_CS_

ZONE_HO

Flag enabling the intracellhandovers allowing to move

TCH from the PS zone to theCS zone of PDCH/TCHallocation

BSC cell changeable flag 1 [0,1] none

Parameter in B9

End of presentation


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