Training_Nortel_Feature_Evolution_V15.1.1_to_V17.pdf

November 29, 2017 | Author: ALEXEY | Category: General Packet Radio Service, Gsm, 3 G, Physical Layer Protocols, Electronics
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1

Features description from V15 1 1 to V17 V15.1.1

BUSINESS MADE SIMPLE

2

AMR Evolution E l ti since i V15.1.1 V15 1 1

3

AMR improvement V15.1.1 Benefits •

Extra flexibility for the AMR adaptation table selection



Reduce the need for updating “customized” adaptation table in BSC D t Config Data C fi which hi h require i B Build ild O On Li Line

Feature



amrAdapatationSet replaced by 4 new parameters

thresh olds

HR 4

th hreshold S

Provide parameters to select any of the 4 adaptation tables (optimistic, typical pessimistic and customized) independently for FR and HR mode typical, and for DL and UL

FR R



5,9 -> 4,75 6,7 -> 5,9 10,2 -> 6,7 12,2 -> 10,2 FR hysteresis 5,9 -> 4,75 6,7 -> 5,9 7,4 -> 6,7 HR h hysteresis t i

uplink p

slow MS no FH

fast MS no FH

4FH

ideal FH (>=8)

8 10 12,5 17,5 2,5 12,5 14 19 35 3,5

2,5 4 6,5 12,5 1,5 10 12 17 2

3,5 5 7,5 12,5 2 10,5 12,5 17,5 2

2,5 4 6,5 12,5 1,5 10 12 17 2

downlink SFH 900 TU3 4 5,5 7,5 13,5 2 11 12,5 16,5 3



HW support :

BSC3000/TCU3000 with S8K/S12K/BTS18K/eCell/ S2000 L&H

Extra flexibility for AMR tuning

AMR improvement V15.1.1 Parameters Parameter

Object

Range

Recommended Value

Class

amrDlFrAdaptationSet

bts

[0 to3] 0 ttypical 0: i l radio di condition diti 1: optimistic radio condition 2: pessimistic radio condition 3: personalize with the BSC data configuration table

3

3

amrDlHrAdaptationSet

bts

[0 to3]

3

3

amrUlFrAdaptationSet

bts

[0 to3]

3

3

amrUlHrAdaptationSet

bts

[0 to3]

3

3

AMR HR Based on Traffic V15.1.1 Feature •

AMR-HR is activated on a TDMA basis according to the cell load

• When AMR-HR is activated on a new TDMA, existing calls in FR in good d radio di conditions diti are repacked k d iin HR tto ffree T Traffic ffi channels h l ffor new calls • Risky calls in poor radio conditions are kept in FR to maintain the voice quality q y •

Cell load evaluated on busy TCH ratio (filtered)



N+1 Cell LoadState for a N TDMA cell



Cell Load State evaluated everyy 10 sec with 2 parameters AMR_HR_Begin and AMR_HR_End

Traffic (Erl) HR capacity

FR capacity

HR

FR 6

Time

AMR HR Based on Traffic V15.1.1 AbOT Algo The HR cell load state is evaluated by the BSC every 10 seconds, based on a filtered busy TCH ratio and a set of thresholds, based on following principles busy _ TCH _ TS Filtered _ TCH _ ration = α * available + (1 − α ) * Filtered _ TCH _ Ration −1 _ TCH _ TS

Cell load state

RxLev distribution

Smax

RxLev parameters, which manage SDCCH to HR direct TCH allocation for new calls, are changed based on load at cell level.

S4 S3 S2 S1 S0 -110

directHRRxlev RxLev4 RxLev3 OMC-R

RxLev2

RxLev1

-48 dBm

dBm

(n,p) voting parameters, which manage FR->HR handovers, are (de-)activated (de )activated on a DRX basis acording to the cell load.

PDTCH is not taken into account in the algo. E Example: l Cell C ll with ith 3 TRX TRX: 1BCCH 1BCCH, 1SDCCH 4 PDTCH => > 18 TCH available il bl HRCellLoadStart = 80% => 14 TS busy, HR is activated HRCellLaodEnd = 60% => Roughtly 10 TS busy, HR is deactivated 7

AMR HR Based on Traffic V15.1.1 Ab T Parameters AboT P t

HRCellLoadStart HRCellLoadEnd

Parameter

Object

Range

Recommended Value

Class

HRCellLoadStart

bts

Integer 0…100

80

3

HRCellLoadEnd

bts

Integer 0…100

60

3

filteredTrafficCoefficient

bts

Integer 0…1 step 0.001

0.5

3

8

AMR signaling evolutions – V16 Drivers > Problem formulation : • AMR signaling channels are not optimized to work in the radio conditions, where low codec in full rate are used: 1.E+00 AMR 12.2 AMR 5.9 FACCH SACCH

1.E-01

FE ER

AMR signaling g g “robustness gap” g p

1.E-02

1.E-03 0

1

2

3

4

5

6 Eb/No ((dB))

7

8

9

10

11

In a given environment (Eb/No), the error rates for AMR signaling channels are significantly higher than for traffic channels 9

Nortel Confidential Information

12

AMR signaling evolutions –V16 DL FACCH Repetition > Mechanism The Repeated Downlink FACCH functionality is applicable when sending LAPDm command frames on the TCH/F channel. The BSS uses the Repeated Downlink FACCH functionality when AMR FR codec used is less than enableRepeatedFacchFr, each time the AMNU entity needs to re-transmit an I-frame on FACCH due to T200 expiry, it sends this frame again to the SPU entity (with a flag related to the retransmission). retransmission) The SPU entity sends first the I-frame on FACCH in TDMA frame M as it does when the feature is disabled. And if the selected CODEC is lower than the threshold set to activate the feature, it stores the LAPDm frame to be repeated in TDMA frame M+ 8 or M+ 9

10

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AMR signaling evolutions - V16 Signaling Tx Offset > Mechanism In order to increase the signaling channels (FACCH and SACCH) robustness in downlink, BTS may use a power offset (above the Tx power applicable for speech) to transmit the signaling bursts. bursts The Tx Power Offset for Signaling Channels is applicable to: • The first transmission of HO COMMAND and ASSIGNMENT COMMAND for all AMR calls in order d to t maximize i i the th likelihood lik lih d off decoding d di these th messages from f th first the fi t instance, i t • Every re-transmission of I-frame on FACCH for all AMR calls (HR and FR) in order to maximise the likelihood of decoding these messages. • Every RR and REJect frame on FACCH corresponding to an uplink retransmission for all AMR calls (HR and FR) in order to improve the two-ways robustness. • Every UA (respectively DM) frame on FACCH corresponding to an uplink re-transmission of SABM (respectively DISC) frames for all AMR calls (HR and FR) in order to improve the twoways robustness. robustness • The transmission of all SACCH frames for AMR FR 4.75 kbps, 5.9 kbps and 6.7 kbps calls (tunable with an OMC-R parameter sacchPowerOffsetSelection ) in order to avoid radio link time-out (that leads to drop calls.

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Nortel Confidential Information

AMR signaling evolutions - V16 Signaling Tx Offset > Mechanism When applying the power offset, > First case: IF PWR + facchPowerOffset ≤ Pnominal THEN SPU modifies the dynamic y p power control in accordance with PWR + facchPowerOffset > Second case: IF PWR + facchPowerOffset f hP Off t > Pnominal P i l THEN SPU set the dynamic power control to: 0 BTS transmits the frame at Pnominal

Same algo for SACCH transmission but the parameter sacchPowerOffset is used

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Nortel Confidential Information

AMR signaling evolutions – V16 > DL FACCH repetition • increase FACCH DL robustness in bad radio conditions by proactively retransmitting the LAPDM frame after 40 ms instead of waiting for T200 expiry ( 180 ) (~180ms) • Benefits both legacy mobiles (~2 dB) and Release 6 mobiles performing soft combining (~4 dB) • Feature restricted to eDRX (on S8000/12000) & RM (BTS18000) > Signaling Tx Offset • Apply a Transmit power offset to SACCH (up to 6 dB) and FACCH (up to 10 dB) messages, messages compared with traffic channels • Allow setting of aggressive AMR target mode power controls • Feature restricted to eDRX (on S8000/12000) & RM (S18000)

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Nortel Confidential Information

AMR signaling evolutions – V16 Parameters Parameter

Object

Range

Recommended Value

Class

FR 6.7 and lower

2

enableRepeatedFacchFr

bts

Disable / FR 4.75 / FR 5.9 and l lower / FR 6.7 6 7 and d llower

facchPowerOffset

bts

[0 to 10] dB (with 2 dB step)

6

2

sacchPowerOffset

bts

[0 to 6] dB (with 2 dB step)

2

2

sacchPowerOffsetSelection

bts

Disable / FR 4.75 / FR 5.9 and lower / FR 6.7 and lower

FR 6.7 and lower

2

Other AMR evolutions – V16 > ENHANCEMENT OF AMR POWER CONTROL MECHANISM Since this feature improves the downlink robustness, new parameters are introduced to define dedicated target g for uplink p and downlink AMR CODEC. The existing parameters (hrPowerControlTargetMode and frPowerControlTargetMode) still apply on uplink and two new parameters are introduced for downlink targets: • hrPowerControlTargetModeDl: downlink AMR codec target to define the downlink power control threshold for HR AMR calls, • frPowerControlTargetModeDl: downlink AMR codec target to define the downlink power control threshold for FR AMR calls, With setting a lower codec as a Downlink Power control target: • A more protected AMR speech codec is used in downlink, • Overall BS attenuation is higher and the overall interference level is decreased accordingly.

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Nortel Confidential Information

Other AMR evolutions – V16 > RATSCCH activation amrReserved1 This parameters is now available at MMI which allows the activation of RATSCCH procedure for AMR FR calls In v16, an improvement of the L1M has been implemented which consists in the BTS repeating the RATSCCH command until it receives an acknowledgment from the mobile. In v17, a further improvement has been implemented. It consists in improving the robustness of the detection of the acknowledgement message received from the mobile : this increases the probability of correctly decoding this message when it is first received. Thanks to these 2 improvements, amrReserved1 should be set to "0" in V16 and V17. Warning: pessimistic Codec Set 10,2 / 6,7 / 5,9 /4,75 (amRreserved1 = 2) must not be chosen because it would inhibit capacity HO i.e. handover from AMR FR to AMR HR (as 12.2 cannot be used). 16

Nortel Confidential Information

Other AMR evolutions – V16 Parameters Parameter

Object

Range

Recommended Value

Class

hrPowerControlTargetModeDl

bts

[4k75, 5k9, 6k7, 7k4]

7k4

3

frPowerControlTargetModeDl

bts

[4k75, 5k9, 6k7, 10k2, 12k2]

12k2

23

amrReserved1

bts

[0 to 2] 0: RATSCCH procedure enabled (default value) 1: RATSCCH procedure disabled initial Full Rate ACS if optimistic therefore; ACS is [12.2k, 10.2k, 6.7k, and 5.9k] 2 RATSCCH procedure 2: d di disabled bl d initial Full Rate ACS if pessimistic therefore; ACS is [10.2k, 6.7k, 5.9k and 4.75]

0

3

PDTCH preemption for voice HR channel – V17 Introduction: GSM/GPRS TS dynamic sharing

> Restriction: • HR voice calls cannot be allocated on preempted PDTCH. • call is forced in FR if a PDTCH must be preempted, even if radio conditions would have led to an HR allocation on a “normal” TCH.

> GSM/GPRS TS Dynamic sharing (introduced in V12.4) increases the efficiency of the Air interface > 3 types of TS are defined: • fixed GPRS radio TS : used in order to guarantee a minimal number of radio di TS allocated ll t d to t GPRS in i this thi option, ti settable tt bl att OMC-R OMC R • fixed GSM radio TS : used only in GSM mode. • radio TS shared between GSM and GPRS : by default used in GPRS • mode, preempted by GSM in case of lack of fixed GSM radio TS. > Feature benefit: radio interface efficiency (TS usage rate) increased by up to 20% vs GSM only TDMA 18

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PDTCH preemption for voice HR channel –V17 Technical overview > Restriction of GSM/GPRS TS dynamic sharing removed: PDTCH can be preempted by HR channel > In case of voice congestion and high HR penetration, more PDTCH will be preempted, up to the maximum number of preemptable PDTCH > Feature also helps reducing call queuing q g as queued q calls can be directly allocated to HR channel (RFF 32278)

FR c channel a e o or HR channel

> Feature activation through a new parameter: gprsPreemptionForHR on bsc j Values: disabled ((default)) / enabled object. > HR channel allocation upon TCH assignment or HO as per the following priority: • free HR channel of a TCH with the other HR already allocated • free HR channel preempted p PDTCH with the other HR already y allocated • free HR channel of a p • HR channel of a new preempted PDTCH: in this case, PDTCH preemption procedure is the same as for a FR PDTCH 19

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PDTCH preemption for voice HR channel - V17 Benefits > Increase c ease ce cell voice o ce capac capacity ty for o more than 50% HR usage > Preserve GPRS/EDGE g p during g voice busy y throughput hours > Performance: • Significant increase in Erlang capacity, especially for high HR penetration rate • simulations show gain up to 36% (14TCH 6 pre (14TCH, pre-emptable emptable PDTCH, 2% blocking rate)

Terminals & BSS HW dependencies > DRX Egal I, DRX Egal II, DRX ND3, eDRX, RM > Not supported on S2000/S4000

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Nortel Confidential Information

E h Enhanced d Measurement M t Report R t (EMR)

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Enhanced Measurement Report (EMR) Introduction: legacy measurement report (phase 1)

RXLEV_DL RXQUAL_DL

Serving BTS

RXLEV_NCELL(n) Neighbour g BTS Neighbour BTS

Measurement Report (SACCH)

Neighbour > MS measurement (DL): BTS • downlink RXLEV (RXLEV_DL) • downlink RXQUAL (RXQUAL_DL) • received level from 6 best neighbour cells (RXLEV_NCELL(n)) + cell identifiers (frequency + BSIC) MS TXPWR CONF: current MS transmission power (UL) • MS_TXPWR_CONF:

> BTS measurements (UL): • uplink RXLEV (RXLEV_UL) • uplink RXQUAL (RXQUAL_UL) • current BTS TX power (BS_TXPWR) • MS_BS_distance 22

Nortel Confidential Information

Enhanced Measurement Report (EMR) Introduction: legacy measurement report > RXLEV • Measurement of the MS received signal level: C+I+N • 6-bit coding, 64 levels from 0 to 63 • Received p power = -110 + RXLEV dBM • Sample logarithmic averaging during 0.5s, corresponding to the transmission period (480 ms = 1 every 4 26-frame) • Measured on the serving cell and the list of neighbour cells > RXQUAL • Measurement of the MS received signal quality: BER • 3-bit coding, 8 levels • averaging during 0.5s • Measurement before channel decoding > 2 types of measurements: • Full measurement: performed on all slots of the reporting period (possibly including unused slots in case of DTX) • Sub measurements: performed only on mandatory sent blocks (12TS instead of 100 TS) • L1M decides on the measurement type to be used depending on DTX use indication 23

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Enhanced Measurement Report (EMR) Improvements vs legacy measurement report > EMR is more accurate than legacy measurement report: • Current cell RXLEV is computed on all valid blocks, instead of either full values or sub values ( RXLEV_VAL) • MS S reports epo ts Mean ea _BEP a and dC CV_BEP instead stead o of sy synthetic t et c indicator d cato RXQUAL QU • Neighboring cell identification: neighboring cells are identified through cell identifier instead of ARFCN+BSIC • 15 neighbour cells can be reported in the EMR message, instead of 6 in l legacy MR > EMR includes a new counters at TDMA level: • Total number of DL transmitted frames • Estimated number of DL bad frames • Measurement made: • per period of 480 ms • for each codec type: AMR AMR-FR FR (4 counters) counters), AMR-HR AMR HR (3 counters) counters), EFR/FR (1 counter)

> EMR includes measurements on 3G neighbour cell: • RSCP (Received Signal Code Power), equivalent to RXLEV RXLEV_NCELL NCELL • 15 neighbour cells max. can be reported (GSM & UMTS) 24

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Enhanced Measurement Report (EMR) Terminals & BSS HW dependencies p • Dual mode MS & GSM Rel-4 MS • BSC3000. Not supported on S4000, S2000E, S2000, S8000-BCF

Parameters Parameter

Object

Range

Recommended Value

Class

reportTypeMeasurement tT M t

bt bts

0:M Measurementt reportt 1 : Enhanced Measurement Report

1

3

servingBandReporting

bts

0 : “no inband cell is favoured” 1: “1 strongest inband cell is favoured” 2: “2 2 strongest inband cells are favoured” 3: “3 strongest inband cells are favoured”

3

3

servingBandReportingOffset

bts

0, 1, ... 7, 0xFF : 0 dB, 6 dB, …, 42 g dB,, “not significant”

0

3

Enhanced Measurement Report (EMR) Downlink voice quality monitoring > Evolution of Radio Measurement Distribution (V15.1.1) includes UL FER counter > New DL counters included in Enhanced Measurement Report allow to compute FER DL and provide DL FER distribution per TDMA: • FER DL = number of bad frames / total number off speech h frames f

EMR DL transmitted frames DL bad frames

FER = number of DL bad frames / total number of DL transmitted frames

> Distribution based on same parameters as FER UL, settable at OMC-R: • 4 thresholds (FERThreshold) defining FER ranges • number of frames used to compute FER (250 to 3000) • FER monitoring for EFR/FR, EFR/FR AMR/HR AMR/HR, AMR/FR

> DVQI (DL voice quality indicator): • Equivalent to UL TEPMOS • distribution for DL based on weighted FER with codec usage 26

Nortel Confidential Information

DL voice quality indicator DVQI

H d Handover 2G 3G

27

Nortel Confidential Information

2G – 3G service continuity CS HO GSM-UTRANFDD GSM UTRANFDD technologie: Introduction > Objective: allow 3G capable handsets that are connected on 2G llayer to move to 3G layer l when h necessary > UE performs radio measurements on UMTS neighboring thanks to EMR. > The network controls what the UE shall measure and sends the system information data concerning the neighboring cell.

UMTS S stem System

GSM System 28

2G – 3G service continuity CS HO GSM-UTRANFDD GSM UTRANFDD technologie: UMTS Adjacent cells Parameter

Object

Range

Recommended Value

Class

MobileCountryCode

AdjacentcellUtran

String

N/A

3

MobileNetworkCode

AdjacentcellUtran

String

N/A

3

Adj AdjacentcellUtran t llUt

St i String

N/A

3

Rnc-id

AdjacentcellUtran

Integer (dB)

[0 … 4095]

N/A

3

Cid

AdjacentcellUtran

Integer

[0 … 16383]

N/A

3

FDD_ARFCN

AdjacentcellUtran

Integer

[0 … 16383]

N/A

3

AdjacentcellUtran

Integer

[0 … 511]

N/A

3

AdjacentcellUtran

0~ No diversity 1~Diversity

N/A

3

locationAreaCodeUTRAN

scramblingCode Diversity

32 UMTS neighbours i hb additional dditi l to t the th 32 GSM neighbours i hb 29

2G – 3G service continuity CS HO GSM GSM-UTRANFDD UTRANFDD technologie: Measurement process(1/2) MS gives information on neighboring cells in EMR or legacy MR if: earlyClassmarkSendingUTRAN is enabled

Rxlev > qsearchC

CPICH_Ec/No > fDDReportingThreshold2

MS reports 3G best cells

CPICH_RSCP > fDDReportingThreshold + fDDMultiratReporting

Parameter

30

Object

Range

earlyClassmarkSendingUTRAN

bts

Integer disabled/enabled

qsearchC

handovercontrol

fDDReportingThreshold2

Recommended Class Value enabled

3

Integer 0…15

7

3

handovercontrol

Integer 0…63

28 (Ec/N0 =10)

3

fDDReportingThreshold

handovercontrol

Integer 0…6 (step of 6)

3 (RSCP =-97)

3

fDDMultiratReporting

handovercontrol

Integer 0…3

2

3

2G – 3G service continuity CS HO GSM-UTRANFDD GSM UTRANFDD technologie: Measurement process (2/2)

Nei 2G

Nei 2G

Serving Cell

Dual Mode MS measures: •on the serving g cell: RXLEV & RXQUAL •on neighbour GSM cells: RXLEV (n) (measured on BCCH, BSIC) CPICH RSCP of the best 3G + CPICH_RSCP

cells 31

Nei 3 G

MS sent in an Enhanced Measurement report p to BTS

2G – 3G service continuity CS HO GSM-UTRANFDD GSM UTRANFDD technologie: Handover service For dual mode MS, the BSC sends the service handover value to the BTS on beginning of communication

“service handover” value

Handover to UMTS impact No UMTS neighbouring cell shall be present

Shall not

in the candidate cells list. UMTS neighbouring cells can be present

Should not

present in the candidate cells list only if handover cause is traffic or alarm reason. For PBGT, no UMTS neighbouring cell shall be present in the candidate cells list.

Should

The impact Th i t off this thi Parameter P t is i Core Network dependent

UMTS neighbouring cells can always be present in the candidate cells list.

Parameter gsmToUMTSServiceHO

32

Object bsc

Range 0:Should; 1:Should not; 2:shall not; 3: gsmToUMTSDisabled

Recommended Value

Class

0

3

2G – 3G service continuity CS HO GSM-UTRANFDD GSM UTRANFDD technologie: Handover Algo 2G expression EXP1(n) = RxLevNCell(n) ave - [ rxLevMinCell(n) + Max(0, msTxPwrMaxCell(n) msTxPwrCapability(n) ) ]

PBGT(n) = Min [msTxPwrCapability(Band0), msTxPwrMax] – Min [msTxPwrCapabilityCell(n) [msTxPwrCapabilityCell(n), msTxPwrMaxCell(n)] + (RxLevNCell(n)ave - RxLevDLave))

3G expression EXP1(n) = CPICH_RSCP(n) – rxLevMinCellUTRAN(n)

PBGT(n) = (CPICH_RSCP(n) (CPICH RSCP(n) - RxLevDLave)

Maximum transmission power level the MS is allowed to use in traffic channel is not taken into account in EXP1 and PBGT for 2G -3G HO decision 33

2G – 3G service continuity CS HO GSM GSM-UTRANFDD UTRANFDD technologie: t h l i Handover H d Algo Al CPICH_RSCP(A) CPICH_RSCP

< rxLevMinCellUTRAN(A)

or < rxLevDLPbgtUTRAN(A)

3G layer: Cell A

3G layer: Cell B

L1M algorithms l ith can be b reused for HO to a UMTS cell, except capture HO and directed retry

Neighboring cell Cell ID Cell A Cell B … 34

CPICH_RSCP(B) – rxLevMinCellUTRAN(B)>0 and d (CPICH_RSCP(B) - RxLevDLave) – hoMarginXX >0

2G layer

2G – 3G service continuity CS HO GSM-UTRANFDD GSM UTRANFDD technologie: Handover Parameters Parameter

Object

Range

Recommended Value (W/0 ETP)

Class

hoMarginUTRAN

adjacentCellUTRAN

-63 to 63

-12

3

hoMarginAMRUTRAN

adjacentCellUTRAN

-63 to 63

63

3

hoMarginRxLevTRAN

adjacentCellUTRAN

-63 to 63

63

3

hoMarginRxQualTRAN

adjacentCellUTRAN

-63 to 63

63

3

hoMarginDistTRAN

adjacentCellUTRAN

-63 to 63

63

3

rxLevDLPbgtUTRAN L DLPb tUTRAN

adjacentCellUTRAN dj tC llUTRAN

-63 63 tto 63

- 48db

3

hoMarginTrafficOffsetUTRAN

adjacentCellUTRAN

-63 to 63

63

3

hoPingPongCombinationUTRAN g g

adjacentCellUTRAN j

List of cause GSM to UMTS

See eng g

3

hoPingPongTimeRejectionUTRAN

adjacentCellUTRAN

0…60s

30

3

offsetPriorityUTRAN

adjacentCellUTRAN

1…5

1

3

rxLevMinCellUTRAN

adjacentCellUTRAN

-63 to 63

-97

3

T3121

bts

2 to 255s

12

3

35

2G – 3G service continuity 2G to 3G Handover Execution ((CS)) UE

BTS

2G-MSC

BSC

Handover

BSSMAP: Handover Required

Indication

T7 Started

MAP: Prepare Handover

3G-MSC

RNC

RANAP: Relocation request (Source RNC to target RNC Transparent container) Q 2630 1 ERQ Q.2630.1 Q.2630.1 ECF RANAP: Relocation request Ack

BSSMAP: Handover Handover command command RR: Intersystem to UTRAN (Handover to UTRAN T7 Stopped Command) T8 +T3121 Started Handover command (handover to UTRAN command

MAP / Prepare

(RRC: handover to UTRAN command)

H d Handover ack k

RRC: Handover to UTRAN Complete MAP: Process access RANAP: Relocation detect signalling RANAP: Relocation complete (relocation detect) RF Chan rel RF Chan rel ack

36

BSSMAP: Clear command T8 +T3121 Stopped BSSMAP: Clear complete

MAP: send end signal

2G – 3G service continuity CS HO GSM GSM-UTRANFDD UTRANFDD ttechnologie: h l i T Traffic ffi di distribution t ib ti Strategy St t

eligible 3G layer: Cell A

3G layer: Cell B Tunning HO traffic parameters

PBGT pseudo capture by using negative HoMarginUtran & tu tuning g RxlevMincellUtran

eligible 2G layer

2G layer

2G layer is favor for accessibility Tuning of uMTSAccessMinLevel…

HO 2G -3G tuning will be applied according to several strategy scenario 37

M lti Zone Multi Z

38

Multi Zone Single BCCH Description >The main principle is to define two zones in a cell: inner zone (band1) and outer zone (band0). >The outer zone contains the TRXs that cover the whole cell area. >The inner zone TRXs may or may not match the outer zone coverage area. >Outer Zone manages BCCH, Signaling (SDCCH), and traffic (TCH) channels, while Inner Zone only manages the traffic (TCH) channels. Band1 layer carries only TCH

Band0 layer carries BCCH, SDCCH and TCH 39

Multi Zone Single BCCH: Direct TCH Allocation (Call Set Up) RxlevDL > ConcentAlgoExtRxLev + hoMarginBeg or for AMR HR direct allocation in small zone

RxlevDL > AMRDirectAllocIntRxLevDL + hoMarginBeg & g g RxlevUL > AMRDirectAllocIntRxLevUL + hoMarginBeg

The time spent on SDCCH is not long enough to compute a weighted average on d downlink li k Rxlev R l measurement before reception of the Abis connection state request. Therefore in V17, L1M compensates by adding hoMarginBeg

Innerzone 40

concentAlgoExtRxLev

Outerzone

Multi Zone Single BCCH: Interzone Handover principle Ms call is allocated in Outerzone : if g RxlevDL > ConcentAlgoExtRxLev Then MS moves to Innerzone

Ms call is allocated in Innerzone : if RxlevDL < ConcentAlgoIntRxLev Or RxQualDL < lRxQualDL Or RxQualUL < lRxQualUL Then MS moves to Outerzone

41

Innerzone

concentAlgoExtRxLev

concentAlgoIntRxLev

Outerzone

MutiZone HO Types I t (I t (Intracell ll Interband) I t b d) HO: HO •Interzone band1 --> band0 •Intercell intraband HO: band1 --> band1 •Interzone (Intracell Interband) HO: band0 --> band1 :

•Intracell intraband HO: band0 --> band0 OR band1--> band1

•Intercell intraband HO: band0 --> band0:

42

•Intercell interband HO: band1 --> band0

•Intercell interband HO: band0 --> band1

V17- Multi Zone Enhancement Interzone Handover: BS & MS Power compensation (1/2)

interZone handover

RxLev DL

biZonePowerOffset

SACCH

2

BS Pwr Att

In V17.0, the enhancement is to compensate the difference of propagation between the 2 zones thanks to power control

SACCH

2

Band 0

Band 1

There is no power compensation during the handover: the initial power after a handover doesn’t take into account the difference of radio propagation p p g between the two bands => There is signal drop leading to problem of assignment or bad voice quality 43

V17- Multi Zone Enhancement Interzone Handover: BS & MS Power compensation (2/2)

Delta_RxLev_DL_oz_to_iz= ZoneTxPwrMaxReduction [oz] - ZoneTxPwrMaxReduction [iz] - biZonePowerOffset

Delta_RxLev_UL_oz_to_iz= - biZonePowerOffset

biZonePowerOffset = 0 in case of concentric cell & dual coupling system Of course, on a handover from the inner to the outer zone, we have: Delta_RxLev_DL_iz_to_oz = - Delta_RxLev_DL_oz_to_iz Delta_RxLev_UL_iz_to_oz = - Delta_RxLev_UL_oz_to_iz

When initiating an inter-zone handover, the BSC shall adapt the BS and the MS power control attenuations depending either on the difference of radio propagation according to the frequency band or on the difference of nominal output TX power between both zones. 44

V17- Multi Zone Enhancement Interzone Handover: Power adapatation (1/2)

MS power management: No power adaptation is required on the uplink for a Concentric cell or a Dualcoupling cell. For dual band: If (Delta_RxLev_UL_xz_to_yz < 0) then new_MS_power (dBm) = Min(old_MS_power (dBm) - Delta_RxLev_UL_xz_to_yz ; M T P M C MsTxPwrMaxCnx_new_band b d) Else new_MS_power (dBm)= old_MS_power (dBm)

MS power control shall be enabled

45

V17- Multi Zone Enhancement Interzone Handover: Power adapatation (2/2) BS power management: if Delta_RxLev_DL_xz_to_yz D lt R L DL t is i less l than th zero, a power loss l shall h ll be b compensated thanks to a power increase (i.e. BS attenuation decrease) else the latter MS power is kept unchanged. If (Delta_RxLev_UL_xz_to_yz < 0) then new_BS_power (attenuation in dB) = Ma (0 old_BS_power Max(0, old BS po er (attenuation (atten ation in dB) + Delta_RxLev_DL_xz_to_yz Delta R Le DL to ) Else new_BS_power (attenuation in power level) = old_BS_power (attenuation in power level)

If the BS power control is disabled or on BCCH TDMA, there is no real power adaptation as the BTS shall emit at the maximum power allowed in the zone 46

Multi Zone Single BCCH: parameters Overview

biZonePowerOffset

47

zoneTxPowerMaxreduction

Multi Zone: Parameters involved (1/3) Early ClassMark Sending (class 3) (bts) • It indicates if a multiband MS is authorized to send the early Classmark change message to the BSC via the BTS. • The Classmark change indicates the frequency bands supported by the MS and MS power classes to perform HO procedures in the best conditions • If Enabled, this allows the MSC to receive the multiband information from MS and to pass it on to the target BSC. It will speed up call set-ups, set ups, Handovers and Directed retries. • Currently all Dual band cells are set to Allowed. However, all the cells that have a Dual Band neighbor should have this parameter set to allowed to access direct inner zone handovers in dual band cells ((Used in EXP3 discussed later) • Recommended value – [Allowed] for multi band networks

48

Multi Zone: Parameters involved (2/3) > Following parameters are used in the Dual band Mono-BCCH implementation: - concentAlgoIntRxLev : minimum signal strength below which a HO is triggered from band1 (inner zone) to band0 (outer zone). - concentAlgoExtRxLev : maximum signal strength beyond which a HO is triggered from band0 (outer zone) to band1 (inner zone) zone). - biZonePowerOffset (in HandOverControl): an offset in the serving cell which is used to estimate the virtual RxLev of band0 (outer zone). Only used when the MS leaves the current bizone cell out of its band1 (inner zone). (rxLev_band0 = rxLev_band1+ biZonePowerOffset); it is actually the difference in the signal strength between GSM and DCS bands (typically 8-12 db). It has to be calculated because all handover thresholds are defined according to the outerzone/band0 signal level. - biZonePowerOffset (n) (in adjacentCellHandover): an offset in neighboring cell which is used to estimate the virtual RxLev of band1 signal to determine if the MS can directly access the inner band in the neighboring cell. biZonePowerOffset(n) >= concentAlgoExtRxLev – rxLevMinCell (n)

49

Multi Zone: Parameters involved (3/3) > Following parameters are used in the Dual band Mono-BCCH implementation: - ZoneTxPowerMaxReduction Class 2 (transceiverZone) : Attenuation with respect to bsTxPowerMax, which defines the maximum TRX transmission power in the zone (Used in creating two different coverage areas for two zones in monozone Concentric Cells). Dual band Concentric cell recommended value: large zone = [0] dB, small zone = [0] dB

- TransceiverEquipmentClass (class 2) (transceiverEquipment) When dual Wh d lb band d ((concentric t i cell) ll) iis used, d th the class l off a TRX/DRX enables bl tto di distinguish ti i h which DRX and which TDMA are used in the outer or inner zone. Class 1 corresponds to a TDMA in 900 band carrying BCCH so belonging to transceiverZone = 0 (large/outer zone). Cl Class 2 corresponds d tto a TDMA iin 1800 band b d nott carrying i BCCH so b belonging l i tto transceiverZone = 1 (small/inner zone) - TransceiverEquipmentClass (class 2) (transceiverZone) Class of the TRX/DRXs partnered with the TDMA frames of the zone zone. The class of a TRX/DRX sets its maximum transmission power. Class 1 corresponds to a TDMA in 900 band carrying BCCH so belonging to transceiverZone = 0 (large/outer zone). Class 2 corresponds to a TDMA in 1800 band not carrying BCCH so belonging to transceiverZone = 1 (small/inner zone). 50

Multi Zone Enhancement Inter one Handover: Interzone Hando er Parameters(1/2) Parameter

Object

Range

Class

TBD

2

concentricCell

bts

ConcentAlgoExtRxLev

handovercontrol

-63 to 63

TBD

3

ConcentAlgoIntRxLev

handovercontrol

-63 to 63

TBD

3

ConcentAlgoExtMsRange

handovercontrol

-63 to 63

TBD

3

ConcentAlgoIntMsRange

handovercontrol

-63 to 63

TBD

3

biZonePowerOffset

handovercontrol

-63 to 63

TBD

3

biZonePowerOffset

AdjacentCellHandover

-63 to 63

TBD

3

rxLevMinCell

AdjacentCellHandover j

-110 to 48

TBD

3

zoneFrequencyHopping

TransceiverZone

TBD

2

zoneTxPowerMaxreduction

TransceiverZone

Large zone [0] Small zone[1 zone[1…55] 55] dB

TBD

2

0…3

TBD

2

Transceiver equipment class TransceiverEquipment

51

0:monozone; 1:concentric 2:dualband; 3:dualcoupling

Recommended Value

0: hopping 1:not hopping

Multi Zone Enhancement Interzone Handover: Parameters(2/2) Parameter

Object

Range

Recommended Value

Class

Transceiver equipment class TransceiverZone

1 or 2

TBD

2

0: large; 1small

TBD

2

TransceiverZone

TransceiverZone

StandardIndicator

bts

0…9

TBD

2

msTxPwrMax2ndBand

bts

According to GSM band

TBD

2

Early callsmark sending

bts

Not allowed Allowed

Allowed

3

btsTxPowerMax

bts

0..47

43

3

52

P i Process Paging P Evolution E l ti

53

UI Multi paging Multi p paging g g Principle p The multipaging command message is a Nortel Specificity. The principle of this implementation is to form group of paging on the Abis interface. Before BSS V14.3.1, for each paging message receives from the MSC; one paging message is sent on Abis interface to a target cell.

The aim of this feature is to reduce the congestion and overload messages on Abis interface. In order to achieve this goal, a new BSC timer Called T_Paging_Group was introduced, to define the minimum of time between two occurrences of multi paging command messages on Abis interface.

MSC SC

BTS

BSC Paging MS1 Paging MS2 Paging MS3

T_Paging_group Multi ppaging g g command MS1, MS2, MS3 T_Paging_group

Paging MS4

Multi paging command MS4

UI Multi paging UI Multipaging Principle Each E h time ti a data d t requestt message (I frame f on LapD) L D) is i used d to t convey a multipaging lti i message to the BTS, the BSC has to wait for an acknowledgement before sending the next Multipaging message. Therefore, the paging process is RTD dependent. Using the Unit Data q message g ((UI frame on the LapD), p ) no acknowledgement g is required q before sending g Request the next frame, which decreases the lapd bandwidth associated to the BCCH TRX for paging messages. .

BTS

I frame number N (paging) Ack frame number N

BSC

BTS

RTD dependency

I frame number N+1 (paging)

Using a Data Request Message (I frame on LapD) to send paging message to the BTS follows this principle (the lapd window is 1):

UI frame number N (paging) UI frame number N+1 (paging)

BSC Line throughput dependency No need to wait for the acknowledgement of the frame nnumber mber N

UI Multi paging Feature Activation The feature is deactivated by default and can be activated thanks to a build on line. Recommended upgrade steps are the following: Upgrade of the BSC without activation of the UI MultiPaging feature (type 4) Upgrade of the BTS supported by the BSC Activation of the UI Multipaging feature in the BSC (via a build on line).

Extended CCCH FS

B

C - -

FS B

C C

BCCH + CCCH downlink

C - -

FS C

C

C - -

FS C

C C

C - -

FS C

C C

C - -

C

C

-

Extended CCCH downlink SDCCH

Beacon frequency

C

TS0 TS1 TS2 TS3 TS4 TS5 TS6 TS7

This feature consists of allowing the configuration of extended CCCH on TS 2, 4 and 6 of the BCCH TDMA. This feature allows to increase the rate of Paging and Immediate Assignment messages related to the cell

8 TDMA

Extended CCCH is mandatory from: mono-layer layer - 7 TRXs in mono - 5 TRXs in multi-layer (micro or dual-band)

P i Capacity Paging C it Evolution E l ti

58

Abis CS paging mode PS paging mode

V14.3.²0/1, V15.0 1

Grouping capacity CS paging Send method Send periodicity Send rate PS paging i Send rate

V14.3.2, V15.1

mult²ipaging I (RSL) single paging I (GSL)

V15.1.1

multipaging I (RSL) single paging I (GSL)

multipaging UI (RSL) multipaging UI (GSL)

4 10 pages/group wait until timer expiry 200ms (fixed) max 50 paging/s/LAC 1 page/message / limited by Abis RTD

12 pages/group wait until timer expiry 200ms (fixed) max 60 paging/s/LAC 1 page/message / limited by Abis RTD

12 pages/group do not wait for timer expiry 200 ms (max) > 60 paging/s/LAC combined bi d with i h CS combined with CS

A i/f filter CS paging

45 paging/s/BSC

105 paging/s/BSC

BSC filter

N/A

120 paging/s/BSC (12 msg / 100 ms) N/A

31 p paging/s/BSC g g 31 paging/s/LAC 22-24 paging/s/RAC 10 paging/s/RAC

64 p paging/s/BSC g g 32 paging/s/LAC 35 paging/s/RAC * 14 paging/s/RAC *

100 p paging/s/BSC g g 100 paging/s/LAC combined with CS 30 paging/s/RAC

15-80 paging/s/cell

15-80 paging/s/cell

Network Engineering limits paging g g CS p PS paging (config A) PS paging (config B) Radio limit (f (function ti off BTS parameters) t )

15-80 paging/s/cell

2 3

* V15.1 only

Config A = 2-phase access and CCCH@BTS Config B = 1-phase access (only after V15.0) or No CCCH@BTS

LAC

V14.3.0 FN 25604 (multipaging command) V15.1 FN 26257 (Paging load distribution on Agprs LAPD) V15.1 FN 26306 (RTD LAPD) V15.1.1 FN 29479 (Paging capacity increase – UI)

A Agprs

A i/f filter

BSC filter

Lapd

1 2 3 4

105 paging/s/BSC (CS + PS)

Abis

LAC RAC

59

RAC

S Security it

60

A5/3 Introduction

RAND

RAND

Ki

A3

A8

SRES

Authentication

Kc

A5

> Authentication: A th ti ti • A3 provides SRES from RAND and Ki, A8 provides Kc from the same arguments • Triplets (RAND, SRES, Kc) allow the network to authenticate end-users

> Encryption: • A5 allows data encryption/decryption from Kc • Encryption prevents intercept and decoding of user’s data and signalling transiting on the air interface, in particular IMSI, IMEI, and calling/called numbers • A5 embedded in the MS and BTS 61

Nortel Confidential Information

A5/3 Risks on A5/1 & A5/2

> Several attacks published on A5/2 since 1997 led GSM Association to prohibit the use of A5/2 from all GSM networks from end 2006 > A5/1 security more and more challenged as it uses the same ciphering key as A5/2 > GSMA may impose i A5/3 in i case off increasing i i risk i k on A5/1 62

Nortel Confidential Information

A5/3 Technical description > Principle • Converts 64-bit blocks under the control of a 128-bit key (Kc) • Based on KASUMI algorithm specified in 3GPP TS 35.202

> DRX • Due to the hardware constraints, A5/3 algorithm designed only on DRX ND3, eDRX and RM; older DRX do not support A5/3 • New N algorithm l ith available il bl b by software ft upgrade d ffrom th the BSC via i Abi Abis iinterface t f

> OMC / BSC • Normally supports all encryption algorithms • Enabled through parameter “encryptionAlgoSupported” settable at OMC level; class-3 parameter, can be modified on line • BSC applies A5/3 to a communication provided that it is activated, supported by DRX type and MS; otherwise otherwise, fallback to A5/1 or no encryption

> MS • All MS launched currently support A5/3 but penetration still low as first A5/3 capable MS launched 4Q05

63

Nortel Confidential Information

A5/3 Feature summary > Technical overview > Based on KASUMI algorithm specified in 3GPP TS 35.202 > Converts 64-bit blocks under the control of a 128-bit key (Kc)

> Dependencies > BTS: DRX ND3, eDRX, RM. Not supported on ND & old design DRX > BSC 3000 3000. Not supported on BSC12000 > MS: A5/3 capable > MSC: must support phase II OAM parameters (cypherModeReject, encryptAlgoAssComp…)

64

Nortel Confidential Information

Smart power management Features description This feature permits to reduce BTS power consumption by automatically switching the PA off when no communication is in progress on the TRX for some time. PA is automatically switched on as a communication establishment begins. The PA can be switched OFF or ON thanks to an electronic switch. This switch can be set to ON or OFF byy software,, thanks to a dedicated new TX firmware function. Parameter

SmartPowerManagement

65

Object

btsSiteManager

Range

Enable/disable the smart power management feature

Nortel Confidential Information

Recommended Value Class

Enable

2

Smart power management Field results Power consumption (dual band site)

• Market drivers & Benefits

• HW dependencies • BTS 18000/6000/9000 • S8000/S12000 V18 PoI

1800 1600

Watts DC W

• Dynamically adjust BTS power consumption to the actual cell traffic • TDMA are switched off if still inactive after a certain timer period,, settable at OMC-R p

1400 1200 1000

900

800

1800

600 400 200 0 Time

900 1468 1370 7% 97

W/o SPM (Watt DC) W/ SPM (Watt DC) Saving (%) Saving (Watt DC)

Environmentally friendly BTS power bill reduction 66

Nortel Confidential Information

1800 791 642 19% 149

900+1800 2259 2013 11% 246

- 2155 kWh/year y - 172 €/year

Based on VO field results in EMEA Tier 1 customer

RF F Feature t

67

Interferer cancellation Overview noise

X

f1 interferer f1

f1

WANTED

WANTED

Signal received= f1 wanted + f1 interferer + noise

INPUT 68

f1 wanted

DSP

(useful signal) noise

OUTPUT

f1 interferer

Interferer cancellation Principle 1/2 • Combination of signal processing and space diversity techniques q to cancel interference according g to p propagation p g conditions • Signal processing: On each antenna antenna, at reception level level, the training sequence is used to estimate the impulse response, so deduce usefull signal and noise and interferences Not accurate when there are no interferers • space diversity technique (Maximum Ratio Combining algorithm) f find a linear combination off the antenna signals so that the interferer signal is nulled (=antenna diagram with a zero value on the interferer direction)

69

Interferer cancellation Principle (2/2) • The Maximum Ratio Combining algorithm points the main lobe on the useful signal g • Interferer cancellation acts as if an antenna null was pointed on the strongest interfering mobile. • Without interferer the algorithm acts as a pure diversity algorithm (MRC) • P Parameter t sett att OMC-R: OMC R ρ parameter: t t d ff the trade-off th pure noise performances against the dominant interferer case

70

Interferer cancellation Antenna radiation patterns

No Interferer

One Interferer

71

Interferer cancellation Parameter Parameter interferer cancel algo usage

Object bts

Range

Recommended Value

Class

[0 to100]% - 0%: Maximum Ratio Combining (best pure thermal noise sensitivity): no interference cancellation, minimum speed correction. - 50%: MRC when no interferers (same p pure re thermal noise sensitivity as 0%): interference cancellation, medium speed correction. - 100%: Approximate MRC when no interferers: interference cancellation, best speed correction.

50%

2

• signification : weight of the interferer in the network • Values : • 0% : no interference; input signal = useful signal + white noise • 50% : half interference, half white noise; input signal = useful signal + white noise i + iinterfering t f i signal i l • 100% : no white noise; input signal = useful signal + interfering signal 72

Interference cancellation Parameter settings g • ρ = 50% is a good compromise between interference cancellation and pure thermal noise sensitivity: • does not degrade the sensitivity • gives almost the same interference cancellation performance as ρ = 100% 0.5 dB cancellation loss in the range I/N = 0 t o 20dB (compared to 100%) • medium trafic area (where isolated interferers will be removed with no coverage degradation)

• ρ = 100%achieves best interference cancellation, when pure thermal noise sensitivity is not an issue (not coverage, but interference limited)

73

Interferer cancellation Synchronous interferer - Simulations Interference Cancellation - Several Synchronous Interferers S8000 - Typical Urban Environment - Rxqual 6 (ber=9.05 percent)

(dB)

loss of 1.5 dB du to the non white noise

1.0 0

8dB Gain

-1.0 C/(n.I+N)

no degradation of sensitivity -2.0

Legend 1 Interferer 2 Interferers 3 Interferers 4 Interferers 5 Interferers

-3.0 -4.0

feature OFF feature ON

-5.0 -6.0

Thermal noise dominant -7.0 -30

-25

-20

-15

-10

Interference dominant -5

0

5 n.I/N

74

10

15

20

25

30

(dB)

Interferer cancellation Asynchronous interferer • The determination of the main lobe and the nulls of the antenna is computed during the training sequence at the center of the useful burst (26 bits) • The accuracy of the computations depends on the time frame when interferences occur: • Interferer during the training sequence time frame • Interferer outside the training sequence time frame. Training sequence Useful signal interferer White noise

75

Interferer cancellation Asynchronous interferer : simulations Influence of Interferer Delay - 1 Interferer-Noise - S8000 - TU50 - C and I independent - C/N=10dB - I/N=15dB

Legend 1 ant. 2 ant. feature OFF 2 ant. feature ON

BER

1e-1

Interferer in the window: it is eliminated

1e-2

Interferer outside the window : same performances as MRC

1e-3

Information Bits (useful burst) 0

76

10

20

30

40

50

Training Seq. (useful burst) 60

70 80 time shift

Information Bits (useful burst) 90

100

110

120

130

140 (bit Period)

Interferer cancellation Asynchronous interferer : Assumptions • Ass.: during the useful signal burst, there are 2*n asynchronous interferers from same energy • interferer ’s synchronisation have been randomly picked up • results have been averaged over all synchronisation values Useful burst

TSC interf. te 1 TSC

interf. 3

interf. 2

TSC interf. 4 time

77

Interferer cancellation Asynchronous y interferer : Simulations Interference Cancellation - Several Asynchronous Interferers S8000 - Typical Urban Environment - Rxqual 6 (ber=9.05 percent)

(dB)

2.0

C/(n.I+N)

1.0

0

-1.0

Legend 2x1 Consecutive Interferers 2x2 Consecutive Interferers 3x2 Consecutive Interferers

-2.0

-3.0 -30

feature OFF feature ON

-25

-20

-15

-10

-5

0

5 n.I/N

78

10

15

20

25

30

(dB)

What is NW synchronisation y ? Principles of the feature with an engineering view.

Network synchronisation general overview Non synchronised NW

Cell x1 TDMA y1 FN z1 Cell x2 TDMA y2 FN z2

TSC : centre of the burst

z1

z1 + 1

z2

z2 + 1





Cells time base = from PCM time. y the cells of the same site ((on the same PCM)) can be aligned. g Only All FN in the network are random 80

Network synchronisation general overview Synchronised NW TSC : centre of the burst

Cell x1 TDMA y1 FN z Cell x2 TDMA y2 FN z + offset

z

z+o

z+1



z+o + 1



Bursts are aligned FNs can be determined 81

Network synchronisation general overview Burst synchronisation and time synchronisation

Cell x1 TDMA y1 FN z1

TSC : centre of the burst

z1

Cell x2 TDMA y2 FN z2

z1 + 1

z2

Time synchronisation

z2 + 1





Burst synchronisation

Burst synchronisation : for PCM clock differences Time synchronisation : for FN differences 82

Network synchronisation new parameters Nortel’s implementation of NW synchronisation Nortel parameter name

Definition

Range

btsSMSynchroMode y

0: normal 1: master 2: slave Activation of the Synchronization y feature 3: gpsBurstSync 4: gpsTimeSync 5: masterGpsBurstSync 6: masterGpsTimeSync

masterBtsSmId

Identity of the master BTS

fnOffset

tnOffset

Allows to specify and control FN difference between BTS. FNOffset parameter is on a per site basis. Allows to specify and control TN difference between BTS

Default value Recommended value

0: normal

Depends p on context

Master BTS id or empty

empty

Depends on context

0 … 84863

0

Set by NW planning

0…7

0

Set by NW planning

Apparently, only few parameters

83

Network synchronisation other parameters Besides the specific NW synchronisation parameters > Direct interaction • BSIC (BCC/TSC + NCC) • FN Offsets (SACCH, SCH)

> Hopping law • HSN Nb And list of Frequencies (MA list) • Nb. • MAIO

> Others • May require HO tuning, PW control tuning … • May require specific planning solutions Besides the feature specific parameters, numerous engineering planning actions must be taken 84

What is NW synchronisation ? Synthesis > From random to deterministic situation • Bursts are synchronised (position in the burst is no longer random) g random • FN are no longer • Pseudo-random aspects remains (RNTABLE)

> Requires engineering • New parameters planning • Planning has to be rethought (BSIC plan, SACCH plan …) • Further tuning actions compare to synchronised situation The reduction of random aspects allow more precise planning, on another hand,, synchronizing y g a NW is a different story y and p previous knowledge (rules) have to be updated accordingly (studies). 85

What is expected p with NW synchronisation y ?

Overview of the areas of change Clarify advantage vs. considerations +

Collision probability : FNs are deterministic. Optimal Interferences quantity

solution improving performances ? Non recoverable collisions probability : Is collision probability the best ? Less interferences Interferers are "burst synchronized"

Interferences impact

Features of interference and noise cancellation work better.

Variability, range and number of the parameters : feasibility of the best solution. Gain limitations : tends to 1/Nb. Frequencies Maybe already optimal Not that easy y to achieve TSCs collisions are worse, TSC range is only 8, TSC (BSIC) planning : precision of IM, feasibility Areas needing improvement may not be the ones with benefits

Less interferences impact Optimal scheduling of SACCH : optimal DTX Optimal BSIC (SCH) reading by MS : optimal HO Others

-

procedure Evenly spread channels could induce better performances

SAIC mobiles performances incertitude Requires a careful TSC planning More pertinent in some areas FN planning in 3 dimensions (SACCH, SCH, Pb Collision) Evaluation (measurements) of impact on HO and on DTX Feasibility, real quantity of impact ?

A potential for improvement if engineered with care. care

87

Detailed areas of change: Quantity of interferences Questions

> Planning : Could some associations (MA lists, HSN, MAIO, FN, TN) be better than others ? > Variability : Does the complexity of planning limit the feasibility of the solutions ? > Limitations : What is the range of impact on interferences quantity ? We try here to answer the question “can a deterministic planning reduce the interferences quantity better than the pseudo-random one of non synchronised h i d NW ?” 88

Detailed areas of change: Quantity of interferences Quantity of interferences = Collisions probability. Cell x1, HSN1= 9 MAIO1= 0 FN1 = 150 MA list = 38 Freq

F24

F30

F4

F33

F25

F26

F26

F19

collision Cell x2, HSN2= 10 MAIO2= 26 FN2 = 1450 MA list = 38 Freq

F22

F16

F22

F5

Duration : d Depends on 9 parameters

89

F2

F26

F37

F36

Detailed areas of change: Quantity of interferences Collision probability : depends on 9 parameters > Example of calculation times for fractional reuse (only 7 parameters) : • With 31 31, 37 and 40 frequencies • Even after algorithm optimizations (84864 vs. 2715648 frames …) Processing systematic calculations nb Delta nb of Calculation duration duration nb HSN nb MAIO FN calculations sec days years 84864 63 31 84864 82869696 60391324,65 698,973665 1,91 84864 63 37 84864 98908992 66446276,29 769,0541238 2,11 84864 63 40 84864 106928640 71439219,03 826,8428129 2,27

Calculation time

90

The limiting factor

Detailed areas of change: Quantity of interferences Distribution of Co-channel probability of collisions for 38 frequencies 10000 8000 6000 4000 2000 0

1/38

0, 00 % 0, 90 % 1, 20 % 1, 40 % 1, 60 % 1, 80 % 2, 00 % 2, 20 % 2, 40 % 2, 60 % 2, 80 % 3, 00 % 3, 20 % 3, 40 % 3, 60 % 3, 80 % 4, 00 % 4, 30 % 4, 80 10 % 0, 00 %

Nb of com mbinations (HSN1, HSN2, MA AIO1, MAIO2, FN N1 FN2)

Gains limitations : fractional reuse

Collision Pb (%)

Planning has to find the right MAIO combinations

NbFreq 31

Min Pb 0,20%

Max Pb 44,94%

Avg Pb 3,23%

StD Pb 0,57%

Potential of gain within the limit of 1/ Nb. Freq (here 3.23%) 91

1/31

Detailed areas of change: Quantity of interferences Can a deterministic planning reduce the interferences quantity better than the pseudo-random one of non synchronised NW ? > High variability. Complexity vs. feasibility : calculation times despite optimizations. times, optimizations > Magic combinations : low collisions probabilities mostly go with high g g ones. > Non recoverable collisions probability : a better potential than Collisions probability. > With ad hoc, collisions probabilities are constant, and reduces complexity.

92

Detailed areas of change: Impact of interferences Various levels of impact > Uplink p : some features interaction with synchronisation y • Nortel feature of interference cancellation • Noise cancellation feature • From V16 : Adaptative receiver feature

> Downlink : SAIC MS interactions with synchronisation • Blind vs. not blind architecture : mostly blind (sensitive to TSC) • 3GPP : gain, with 1 interferer, shall be at least 8 dB. • Penetration and performances Both : Gain sensitive to nb. of interferers and TSC collisions. Downlink : Penetration, performances of SAIC mobiles to be assessed. Uplink : features (ICA, noise cancellation) already active, only the additional gain of synchronisation s nchronisation 93

Detailed areas of change: Impact of interferences Uplink and downlink : Sensitivity to TSC collisions

With NW synchronisation, different TSCs

Before NW synchronisation

Cumulation With NW synchronisation, same TSCs

2 (center of) bursts : red one = main signal, interfered, blue one = interferer. Critical interferers should not be allocated the same TSC.

94

Detailed areas of change: Impact of interferences Uplink and downlink : Impact of TSC TSC collisions impact vary according to the various TSC couples (TSC1, TSC2) :

Impact of TSC in synchronised situation, without interference cancellation

95

Detailed areas of change: Impact of interferences Uplink and downlink : Impact of TSC TSC collisions impact vary according to the various TSC couples (TSC1, TSC2) :

Impact of TSC in synchronised situation, with interference cancellation

96

Detailed areas of change: Impact of interferences Uplink (and downlink ?) : sensitivity to number of interferers Interference Cancellation - Several Asynchronous Interferers S8000 - Typical Urban Environment - Rxqual 6 (ber=9.05 percent)

(dB)

2.0

Interference Cancellation - Several Synchronous Interferers S8000 - Typical Urban Environment - Rxqual 6 (ber=9.05 percent)

(dB)

C/(n.I+N)

1.0

4.5dB Gain

loss of 1.5 dB du to the non white noise

1.0

0

0

8dB Gain -1.0 -1.0

no degradation of sensitivity C/(n.I+N N)

Legend 2x1 Consecutive Interferers 2x2 Consecutive Interferers 3x2 Consecutive Interferers

-2.0

feature OFF feature ON

-2 0 -2.0

Legend 1 Interferer 2 Interferers 3 Interferers 4 Interferers 5 Interferers

-3.0 -4.0

-3.0 -30

-25

-20

-15

-10

-5

0

5 n.I/N

10

15

20

25

30

feature OFF feature ON

(dB) -5.0 -6.0

Thermal noise dominant -7.0 -30

-25

-20

-15

-10

Interference dominant -5

0

5

10

15

20

25

30

(dB)

n.I/N

97

Higher gain when interferers are synchronized and fewer (reducing overlapping). Uplink : gain is the «remaining» part

Detailed areas of change: Impact of interferences Conclusions > Gain expected : • DL : SAIC mobiles (penetration, Architecture) • UL : ICA/Noise cancellation features features.

> Maximum gain implies : • Optimal p TSC p planning g • As less overlap between cells as possible

98

Detailed areas of change: Others Other impacts of network synchronisation > What is the FN offset impact on SACCH transmission ? > What is the FN offset impact on BSIC reading and HO efficiency ffi i (SCH ttransmission) i i )?

And, “should FN offset be modified and how ?”

99

Detailed areas of change: Others SACCH > N Non synchronised h i d NW : FN offsets ff t between b t cells ll are random : • SACCH transmission random : ~ spread. • No way to control it, anyway.

> Synchronised NW : • FN offset ff t between b t 2 cells ll = 0 : the th coincidence i id off th the various i SACCH channels, could lead to additional RLT expiries. • Need to plan FN Offset to avoid, as much as possible, collisions of SACCH. SACCH Multiples p of 26 (FR) ( ) or 13 (HR) ( ) are to be avoided

100

Detailed areas of change: Others BSIC reading : MS has a limited time (10 sec) to identify and synchronize with neighbor cells > Non synchronised NW : FN offsets between cells are random : • SCH transmission random : ~ spread. • No way to control it, anyway.

> Synchronised NW : • FN offsets between 2 cells could be set for each neighbor cell to improve the efficiency of the mobiles to identify and synchronize with neighbor cells. • Need to plan FN Offset to allow, as much as possible, spreading of SCH of the 6 strongest neighbors of each cell. Planning of FN offset concerns the neighboring 101

What is expected with NW synchronisation ? Synthesis > Quantity of interferences • Fractional reuse : Complex planning, involving many parameters. • With ad hoc, collisions probabilities are constant, and reduces complexity.

> Impact of interferences • Gains according to limitation of the NW (UL, DL) • Requires tight TSC planning (and abacus of gains). gains) Reduced effects in highly overlapped areas.

> Others • FN Offset have also to be planned according to SACCH and SCH Planning solutions will be the key to improvement. Will require background information and preparation : abacus (TSC), IM … 102

What has to be done to implement NW synchronisation y ?

Overview of the planning steps General steps of planning and their schedule Planning of SACCH color

Ad hoc

Planning of SCH color

Global color

Others

Calculation of HSNs, MA lists, MAIOs and FN Global color = mod(FN, 26*51)

Use existing Frequency plan Global color = FN

TSC SC (BCC) ( CC) plan F(IM*PbColl*Traffic, abacus)

(*)

NCC plan (BSIC) (*) For ad hoc, as PbColl=constant, TSC plan can be done in parallel with previous steps 104

SAIC capable MS management DRIVERS /BENEFITS Capacity Increase (Erl)/MHz spectrum Voice quality / Data throughput FER/BLER reduced in DL thanks to interferer cancellation

TERMINAL DEPENDENCIES

105

Maximum gain is obtained with Release 99 Terminals (1Q2005) supporting DARP capability Optional Feature : Single Antenna Interference Cancellation or Downlink Advanced Receiver Performance (GERAN R6)

TECHNICAL OVERVIEW New Classmark 3 information element is used to inform the BSS about the MS capability Several dB rejection on the g interferer in DL for DARP strongest capable MS Specific allocation rules : One TDMA priority field for SAIC MS : high, low, forbidden Increase frequency reuse on SAIC dedicated TDMA

HW dependencies d d i Capacity gain is obtained with Network Synchronization

SAIC capable MS management >

Capacity gain can evaluated to 50% (better downlink performance in GMSK) 1. Allocator enhancement allows defining g specific TDMA pool with high g priority allocation rles for SAIC capable MS allowing increasing frequency reuse according to SAIC MS penetration : •

30% SAIC penetration allows for 15 % capacity gain

2 When no specific allocation rules are used 2. used, SAIC MS will require less BTS transmitted power (Itf reduction) and will use more often HR channel (BTS capacity increase). Moreover DL signalling blocks will be better received decreasing the call drop ratio. •

R Require i hi high hh handset d t penetration t ti tto h have capacity it b benefit fit Site traffic gain with SAIC capable handset 250

Traffic in erlang

200

46 % gain

16% gain 150

100

50

Baseline

106

With net Sync

With SAIC 100%

0

Baseline

With net Sync

With SAIC 100%

107

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