b12 Fsm Vamos Ed1rel

COPYRIGHT 2011 ALCATEL-LUCENT. ALL RIGHTS RESERVED. ALCATEL-LUCENT CONFIDENTIAL SOLELY FOR AUTHORIZED PERSONS HAVING A NEED TO KNOW PROPRIETARY USE PURSUANT TO COMPANY INSTRUCTION

VAMOS Feature introduction Strategy & Monitoring

VAMOS Program Core TeamMGR / TIPS / NEA

COPYRIGHT 2011 ALCATEL-LUCENT. ALL RIGHTS RESERVED. ALCATEL-LUCENT CONFIDENTIAL SOLELY FOR AUTHORIZED PERSONS HAVING A NEED TO KNOW PROPRIETARY USE PURSUANT TO COMPANY INSTRUCTION

PUBLICATION INFORMATION

AuthorRamez SOSS

Updates: Mrio BERNARDES / Alexandru PETRAN / Ruben CORREIA / Nenad MOMIR

Reference documentationVAMOS SFD 3BK 10204 0678 DTZZA

System Level Simulations MEMO 211157 (R&D/SYT/211157_v1)

3GPP TS 45.914 - Circuit switched voice capacity evolution for GERAN (Rel-9)

Publication history

July 2011 - Document creationMarch 2012 Document update (Ed1 Rel.)






6 | CONCLUSION


3 | TEST STRATEGY




1.1 | INTRODUCTION

1 | VAMOS TECHNICAL DESCRIPTION


VAMOS TECHNICAL DESCRIPTION WHAT IS VAMOS?

VAMOS (Voice services over Adaptive Multi-user channels on One Slot) is a 3GPP Rel-9 feature

MUROS (Multi-User Reusing-One-Slot) is the corresponding 3GPP study item described by Technical Report 3GPP 45.914

VAMOS allows multiplexing of two users simultaneously on the same radio resource in the CS mode both in DL & UL, using the same timeslot number, physical sub-channel, ARFCN and TDMA frame number

Accordingly, VAMOS allows assignment on a single GSM CS radio timeslot of: Two users in Full Rate (instead of one), Or four users in Half Rate (instead of two), Or three users in Half Rate (instead of two)

Benefits for the operator: Decrease Total Cost of Ownership (TCO) Increased hardware efficiency (more users per TRX) Increased spectral efficiency (then network capacity) in certain scenarios


VAMOS TECHNICAL DESCRIPTION VAMOS BENEFITS As voice service price gets cheaper, most operators face the challenge to

obtain efficient utilization of hardware and spectrum resources:VAMOS allows significant capacity gains: Multiplexing two users on the samecarrier/timeslot will also allow reducing the number of TRXs

Target average capacity gain around x1.5

Capacity gains are more important using VAMOS-HR channels, whereas VAMOS-FR(especially with AMR-WB) might be interesting for operators seeking high voice quality

HOWEVER, capacity increase due to VAMOS is performed to the detriment of the call quality performance

In VAMOS mode, each user generates strong additional co-channel interference to the paired user, thus increasing the overall interference level in the network

In case a network is quality-limited, there is no room for VAMOS gain

VAMOS allows to convert a quality margin to additional capacity Good C/I conditions: Up to 100% gains Poor C/I conditions: No gain


VAMOS TECHNICAL DESCRIPTION VAMOS INTRODUCTION SCENARIOS CS capacity increase in existing network with medium or good quality:

Instead of new TRX + reworked frequency planning

Or PS capacity increase, as an induced effect of voice efficiency Ex: for Operators w/o 3G/LTE

Less TRX to deploy in new networks (hardware saving)

CS capacity recovery in case of GSM re-farming, 2 possible scenarios: Both GSM spectrum reduction + GSM h/w capacity reduction

=> VAMOS allows recovering part of the lost capacity providedthat there is some quality margin after refarming

GSM HW capacity reduction only => VAMOS allows recoveringlost capacity

VAMOS shall not be interesting where the operator reduces its GSMspectrum with the same GSM HW capacity since the quality marginafter refarming will be low (due to the tighter frequency planning)

Hot spots, occasional events

GSM TRX 1 TRX 3

MHz

MHz

GSM TRX 1 TRX 2 + VAMOS UMTS


With VAMOS, two users are multiplexed on a given timeslot:

In Downlink

The BTS transmits simultaneously to 2 MSs on the same timeslot and frequency

Using two different Training Sequences (TSC)

With adaptive-QPSK modulation

One adaptive-QPSK symbol is a pair of bits,where each bit belongs to a different sub-channel

Allows to double the throughput comparedto legacy GMSK

Variant of QPSK allowing for independentpower control for the two users

In Uplink

2 MSs transmit simultaneously on the same timeslot and frequency, using GMSK and different TSC

The BTS uses the different TSC to separate the signals from the two MSs

VAMOS TECHNICAL DESCRIPTION RADIO TRANSMISSION IN VAMOS MODE

BTSARFCN : 160TS: 3TSC : 0

ARFCN: 160TS: 3TSC: 5

ARFCN : 160TS : 3TSC : 0

ARFCN : 160TS: 3TSC : 5

MS2MS1

10

COPYRIGHT 2011 ALCATEL-LUCENT. ALL RIGHTS RESERVED. ALCATEL-LUCENT INTERNAL PROPRIETARY USE PURSUANT TO COMPANY INSTRUCTION

VAMOS TECHNICAL DESCRIPTION VAMOS PAIRING TDMA MULTIFRAME

T T T T T T TTTTTTt t t t t t t t t t tt A aT = TCH user 1 t = TCH user 2 A = SACCH user 1 a = SACCH user 2

T T T T T T TTTTTTT T T T T T T T T T TT A iT = TCH A = SACCH i = idle frame

26-Multiframe for a FR channel: 26 bursts in 120 ms

26-Multiframe for two HR channels: 13 bursts for each user in 120 ms

T = TCH user #1 A = SACCH user #1

T T T T T T TTTTTTT T T T T T T T T T TT A iT T T T T T TTTTTTT T T T T T T T T T TT A i

T = TCH user #2 A = SACCH user #2

26-Multiframe for two VAMOS FR subchannels

T = TCH user #1 t = TCH user #3A = SACCH user #1 a = SACCH user #3

26-Multiframe for four VAMOS HR subchannels

T T T T T T TTTTTTt t t t t t t t t t tt A aT T T T T T TTTTTTt t t t t t t t t t tt A a

T = TCH user #2 t = TCH user #4A = SACCH user #2 a = SACCH user #4

Non-VAMOS

VAMOS

11


VAMOS TECHNICAL DESCRIPTION TRAINING SEQUENCE CODES Training sequence: a fixed bit sequence (26 bits) known by the receiver for

synchronization and channel estimation purposes

A TSC is assigned to a MS during channel allocation and transmitted in each UL/DL burst

With VAMOS, 2 different TSCs must be assigned to the paired VAMOS subchannels: On the UL, the BTS uses the different TSCs to separate the received signals

On the DL, the MS uses its own TSC knowledge (and, in some cases, also the knowledge of the TSC associated to the paired user) to detect the desired signal

A new set of TSCs (TSC Set 2 including 8 TSC) - with improved cross correlation properties compared to the legacy TSC set 1 - has been proposed for VAMOS

12


VAMOS TECHNICAL DESCRIPTION VAMOS IMPACT ON MOBILE TERMINALS

Due to the high co-channel interference created by the paired user, VAMOS needs powerful interference cancellation techniques and requires advanced receivers able to operate at SIR close to 0dB with acceptable performance

This is the case of SAIC (DARP Phase 1) receivers as well as new VAMOS-aware receivers that will be specifically designed for VAMOS

Two levels of VAMOS-aware MSs are introduced in Rel-9, supporting TSC set 2: VAMOS Level 1: SAIC MSs that in addition understand and can use the new training

sequences

VAMOS Level 2: Advanced VAMOS-specific algorithms for interference cancellation instead of SAIC

Nevertheless, legacy non-SAIC terminals could also support VAMOS operations but only if coupled to VAMOS-aware terminals with advanced receiver architectures specifically designed for VAMOS (VAMOS L2)

13


VAMOS TECHNICAL DESCRIPTION VAMOS CONCEPTS - AQPSK MODULATION A new modulation technique used only in Downlink transmission in VAMOS mode

AQPSK modulation shall only be used when 2-bits symbols (one bit for each paired VAMOS user) must be transmitted during a burst

When DL DTX is enabled, during a speech pause of one of the paired users, legacy GMSK must be used for the other user if he is in a speech period

The radio transmission will be cut when both users have entered a speech pause and they have no SID frames to transmit

The AQPSK symbol rate is equal to GMSK symbol rate (around 270,833 ksymb/s)

The power ratio between Q & I channels is defined as the SubChannel Power Imbalance Ratio (SCPIR):

SCPIR = 20 x log10 (tan()) dB is dynamically chosen by the BSS - according to the radio conditions & the MS capabilities - such that |SCPIR| 10 dB

A constant AQPSK backoff value is applied by the BTS (estimated at = 45). A 3 dB backoff is expected, to avoid any distortion to the transmitted signal in AQPSK modulation

14


VAMOS TECHNICAL DESCRIPTION VAMOS CONCEPTS SCPIR (1/3)Why power balancing is needed between the 2 VAMOS subchannels?

SCPIR is the ratio between the DL power transmitted by the BTS for thesubchannel#1 and the DL power transmitted by the BTS for the subchannel#2:

SCPIR [dB] = BS_TXPWR_1 BS_TXPWR_2, both in dBm

AQPSK power: BS_TXPWR [dBm] = 10 log(BS_TXPWR_1 [mW] + BS_TXPWR_2 [mW]) There is physically ONE transmitted power: the symbol power (AQPSK power)

Too high SCPIR => sub-channel#2 signal could be severely disturbed Too low SCPIR => sub-channel#1 signal could be severely disturbedSCPIR should be kept within a range defined by SCPIRlow & SCPIRhigh,

function of MS capabilities

i. Due to different terminal capabilities: Both terminals of a VAMOS pair do not necessarily have the same reception capabilities => the signal for the MS with the lower capabilities can be favored

ii. Since the 2 paired users do not necessarily experience the same path loss and/or radio conditions, power balancing is needed to allow independent power control on both sub-channels

BTS power for subchannel #1 BTS power for subchannel #2

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VAMOS TECHNICAL DESCRIPTION VAMOS CONCEPTS SCPIR (2/3)

SCPIRlow of a VAMOS pair is the minimum SCPIR value allowing correct signal decoding for the MS allocated to subchannel#1 of that pair (independently of the MS capabilities of the MS allocated into subchannel#2)

A negative SCPIRlow value means that the MS is capable of correctly decoding its VAMOS signal even when the paired sub-channel is transmitted with a higher power

SCPIRhigh of a VAMOS pair is the maximum SCPIR value allowing correct signal decoding for the MS allocated to subchannel#2 of that pair (independently of the MS capabilities of the MS allocated into subchannel#1)

If MS_1 is on VAMOS subchannel#1 and MS_2 is on VAMOS subchannel#2, then SCPIRlow & SCPIRhigh for any VAMOS couple (MS_1, MS_2) are computed as follows:

SCPIRlow(MS_1, MS_2) = SCPIRlow(MS_1, x), SCPIRhigh(MS_1, MS_2) = - SCPIRlow(MS_2, x)

Condition for MS_1 & MS_2 pairing:

SCPIRlow(MS_1, MS_2) SCPIRhigh(MS_1, MS_2)=> SCPIRlow(MS_1, x) + SCPIRlow(MS_2, x) 0

16


VAMOS TECHNICAL DESCRIPTION VAMOS CONCEPTS SCPIR (3/3) Recommended SCPIRlow value @ VAMOS allocation per MS type:

For correct decoding of both DL signals:SCPIRlow (MS_1, MS_2) < SCPIR (MS_1, MS_2) < SCPIRhigh (MS_1, MS_2)

Ex: From a given BS_TXPWR_2 value of a VAMOS pair, assuming SCPIRlow < 0 , BS_TXPWR_1 shall be in the range [BS_TXPWR_2+SCPIRlow, BS_TXPWR_2+SCPIRhigh]

The BTS cannot compute UL SCPIR because the UL signal level measured at the antenna connector is the sum of the UL signals of both VAMOS subchannels

MS capability of the MS on subchannel#1 SCPIRlow (MS_1, x)

legacy non-SAIC +8

legacy SAIC -2

VAMOS-1 -4

VAMOS-2 -10

These values are configurable at OMC-R level through the

parameters: SCPIR_LOW_MS_ALLOC_xxx

17


The operator can configure the allowed MS pairings via a set of 8 parameters:

EN_PAIRING_xxx_yyy: to activate/deactivate MS pairings depending on the MS capabilities xxx and yyy

Mandatory rules exist between the EN_PAIRING_xxx_yyy flag and the related SCPIR_LOW_MS_ALLOC_xxx and SCPIR_LOW_MS_ALLOC_yyy parameters

Recommended pairing combinations:

Note: Non-SAIC MSs can never be paired to Non-SAIC or SAIC MSs

VAMOS TECHNICAL DESCRIPTION VAMOS PAIRING COMBINATIONS

SubCh#2SubCh#1 legacy non-SAIC legacy SAIC VAMOS-1 VAMOS-2

legacy non-SAIC No No No Yes

legacy SAIC No Yes Yes Yes

VAMOS-1 No No Yes Yes

VAMOS-2 No No Yes Yes

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VAMOS TECHNICAL DESCRIPTION HOW THE BSS DERIVES THE MS CAPABILITY

The BSS derives the MS capabilities from the VAMOS Level and the Downlink Advanced Receiver Performance (DARP) fields of MS CLASSMARK 3:

VAMOS Level = 01: the MS capability shall be set to VAMOS-1 MS

VAMOS Level = 10 or 11: the MS capability shall be set to VAMOS-2 MS

VAMOS Level = 00 and DARP = 01, 10 or 11: the MS capability set to legacy SAIC

VAMOS Level = 00 and DARP = 00 then: the MS capability shall be set to "to be tested" (see section 1.6) if the EN_TEST_FOR_NON_SAIC parameter = 1, otherwise the MS capability is set to legacy non-SAIC

VAMOS LevelDARP 00 01 10 11

00 Depending on EN_TEST_FOR_NON_SAIC

01

10

11

SAICVAMOS-1 VAMOS-2

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VAMOS TECHNICAL DESCRIPTION TSC ALLOCATION RULES 3GPP rule: the TSCs for the 2 VAMOS subchannels are selected either from

different TSC Sets or both from TSC Set 1 in case of SAIC-SAIC pairs, but cannot be both from TSC Set 2

If at least one MS of a VAMOS pair is VAMOS capable, then the BSS shall assign: A training sequence chosen from TSC Set 1 for VAMOS subchannel#1 in the VAMOS pair And the training sequence with the same training sequence code and selected from TSC

Set 2 for the VAMOS subchannel#2 in the VAMOS pair

Supported TSC pairs used for traffic channels in VAMOS mode:

For common control channels, BCCH and packet channels TSC is the same as B11 (TSCparameter).

No notifications from BSC to MFS will be needed when VAMOS is enabled/disabled in the cell.

In cells where VAMOS is not enabled, the TSC parameter shall be used as in B11 TSC_1 & TSC_2 are defined according to the telecom parameter TSC_1_2

VAMOS subchannel#1 VAMOS subchannel#2 UsageTSC_1 (Set 1) TSC_1 (Set 2) (legacy, VAMOS) or (VAMOS, VAMOS) pairs

TSC_1 (Set 1) TSC_2 (Set 1) Only (legacy SAIC, legacy SAIC) pairs

TSC_2 (Set 1) TSC_2 (Set 2) (legacy, VAMOS) or (VAMOS, VAMOS) pairs

20


VAMOS TECHNICAL DESCRIPTION SIGNALING CHANNELS IN VAMOS MODE

According to 3GPP simulation results, the SACCH performance of a VAMOS user may not meet the requirements in some scenarios:

As the SACCH frames of both users are transmitted simultaneously, SACCH decoding might be impacted by the increased interference

SACCH performance can be improved using: The repeated SACCH technique (standardized since Rel-6, available since B11) or The shifted SACCH mapping (introduced in Rel-9)

The objective is to enhance SACCH performance both in UL & DL by rearranging the TDMA frame mapping of 2nd VAMOS subchannel so that the allocation of the SACCH frames does not collide with the SACCH frames of 1st VAMOS subchannel where the legacy TDMA frame mapping is applied

Consequently, SACCH performance is enhanced taking profit of the GMSK transmission during speech pauses of the paired user entering DTX or even during AQPSK modulation by applying power increase to favor the SACCH frame over the paired TCH frame

3GPP rule: Shifted SACCH shall always/only be used with a VAMOS Level 2 MS using a TSC from the Set 2 even if it is allocated in Non-VAMOS mode

Example: TDMA multiframeorganization with 2 FR users:

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

u1 T T T T T T T T T T T T S T T T T T T T T T T T T Iu2 T T T T T T T T T T T T T S T T T T T T T T T T T I

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VAMOS TECHNICAL DESCRIPTION VAMOS IN ALU VAMOS is supported in IP mode only Following 3GPP rules, VAMOS pairing is forbidden in an inter-cell HO Supported VAMOS configurations: VAMOS-FR, VAMOS-HR and Semi-VAMOS HR

VAMOS FR/HR configurations are not supported in B12 (high complexity of radio allocation and power control algorithms)

ALU strongly recommends AMR activation in VAMOS mode, to enhance voice quality and increase signal immunity to interference

22


VAMOS TECHNICAL DESCRIPTION VAMOS IN ALU - WHY IP TRANSPORT?

VAMOS allows to carry up to 4 calls per radio timeslot

In TDM, existing mapping between one radio timeslot and one Abis nibble does not work any more: 16 kbits/s are not enough

Possible solutions:a. Using two 16 kbits/s nibbles, i.e. doubling the Abis bandwidth requirements for voice,

whereas only a part of the traffic will be using VAMOS=> Waste of resources!

b. Using pools of 16 kbits/s resources and 32 kbits/s resources could be used=> Complex feature implementation and subsequent resource dimensioning!

c. A single large Abis pipe is the optimal solution: This pipe is provided by native IP transport in the BSS

Can be used either with IPoEthernet or IPoverE1 (see Appendix C)

Efficient voice multiplexing allows to compensate IP overheads

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1.2 | VAMOS SUITABILITY EVALUATION


24


VAMOS SUITABILITY EVALUATION CONTEXT

Purpose: Assess the possibility of VAMOS introduction depending on network conditions:

VAMOS is beneficial in good quality networks, as it converts the quality margin into additional capacity

Networks that are capacity-limited before VAMOS introduction are likely to be quality-limited after VAMOS; therefore, there is no room for VAMOS in a network already suffering from high interference (i.e. quality-limited)

The methodology described in the next slides aims at evaluating to which extent is a network favourable for VAMOS introduction

2 case studies are presented: (details in Appendix A)

Case Study 1: Vodafone Qatar => Very favourable case with very good network quality

Case Study 2: CMCC - Shanghai area => Medium network quality, less favourable for VAMOS

25


VAMOS SUITABILITY EVALUATION HOW TO ESTIMATE NETWORK QUALITY (1/2)

1. Through C/I measurements (e.g. drive tests):

Average C/I < 12 dB => VAMOS benefits: LOW

12 < Average C/I < 18 dB => VAMOS benefits: MEDIUM

Average C/I > 18 dB => VAMOS benefits: HIGH

2. Through analysis of available frequency spectrum & reuse size:

Average Reuse Cluster Size (ARCS)

For example, assuming dedicated BCCH band:

BCCH ARCS = number of BCCH frequencies TCH ARCS = number of TCH frequencies / average number of TCH TRXs per cell

26


VAMOS SUITABILITY EVALUATION HOW TO ESTIMATE NETWORK QUALITY (2/2)

Average Reuse Cluster Size (ARCS) criteria:

For Synthesized Frequency Hopping (SFH), RF load is used to estimate the FP quality:

RFload = # Hopping TRX per cell/ # Hopping frequencies per cell

In case of 1x1 fractional reuse, RFload should be strictly less than 10%

In case of 1x3 fractional reuse, RFload should be strictly less than 30%

Low quality Medium quality High quality

ARCS Aggressive FP Typical FP Conservative FP

BCCH 12 18 20

TCH non-Hopping 10 12 12

TCH Hopping 9 12 12

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VAMOS SUITABILITY EVALUATION OTHER CRITERIA

Assess network interference level from Performance Measurement (PM) counters DL Quality HO rate: [MC672] / CHO_All UL Quality HO rate: [MC670] / CHO_AllHowever, the % of Quality HO depends on the settings of corresponding parameters

triggering emergency HO

Penetration of recent mobiles As VAMOS requires advanced receivers able to work at low SIR ranges, a reasonable

penetration of Single Antenna Interference Cancellation mobiles (SAIC) is mandatory to ensure significant VAMOS gain

In B11, there is no way to count SAIC mobiles penetration; but at least the penetration of Rel-4 mobiles can be estimated from PM counters as [P450e] / [P450d]

A low penetration of Rel-4 mobiles indicates low penetration of SAIC mobiles. However, Rel-04 mobiles are not necessarily SAIC-capable

28


VAMOS SUITABILITY EVALUATION OTHER FEATURES LINKED TO VAMOS

IP transmission: VAMOS is only supported in IP modewhether using IPoEth or IPoE1

H/W: VAMOS is supported on Twin & MC-TRX/RRH; it also requires Mx-BSC

At VAMOS introduction, the following features are strongly recommended:

AMR: To improve voice quality in VAMOS mode and increase signal robustness against interference, AMR is strongly recommended

HR: It doesnt make sense to look for capacity increase by VAMOS introduction if HR is not already exploited in the network

DTX & Power Control: Power Control and Discontinuous Transmission are key features to minimize interference in VAMOS mode

29


1.3 | RADIO ALLOCATION STRATEGY


30


VAMOS RADIO ALLOCATION STRATEGY MAIN APPROACH The user pairing strategy is a trade-off between the following objectives: Maximize the capacity gain,

Minimize the un-pairing probability,

Minimize the co-channel interference for the paired users

while keeping acceptable call quality performance

The radio allocation strategy determines the most appropriate users to pair together and on which VAMOS capable-timeslot, taking into account: The cell load: VAMOS pairing can be only triggered beyond a given traffic load in the cell;

no need to pair users when the load is low

Radio conditions: To reduce unpairing probability, pairing should be avoided if a user already experiences bad radio conditions

The MS capabilities The allowed pairing combinations in the cell

The VAMOS user pairing process is integrated into the radio TCH allocation function

31


VAMOS RADIO ALLOCATION STRATEGY DEFINITION: SOURCE MS vs. TARGET MS

Source MS is a MS whose presence can potentially trigger the VAMOS user pairing process in that cell; when it is:

Either candidate for intra-cell HO (current channel can be non-VAMOS or VAMOS TCH)

Or in the call establishment phase in the cell (with the exception of a MS to be allocated on a TCH in the inner zone of a concentric cell)

MS cannot be directly allocated to a VAMOS subchannel neither after an inter-cell handover nor after a directed retry => ALU rule inspired by 3GPP specifications

Target MS is a MS which can be potentially paired with a Source MS, when it is: Allocated to a non-VAMOS TCH on a VAMOS-capable TRX,

In dedicated mode, not allocated in DTM and N_DELAYED_HO_CAUSE30 is not running

Fulfilling radio conditions criteria (detailed in next slides)

A Target MS which is selected to be paired with a given Source MS is not handed-over; but its current non-VAMOS TCH channel simply becomes a VAMOS TCH, sharing the same physical resource with the Source MS

32


VAMOS RADIO ALLOCATION STRATEGY VAMOS PAIRING SCENARIOS

VAMOS pairing can be reached in the following scenarios: During intra-cell VAMOS pairing HO (cause 35), if EN_VAMOS_PAIRING_CA =TRUE

At call establishment of the source MS, if EN_VAMOS_NASS = TRUE

VAMOS pairing is forbidden in the following scenarios: During an inter-cell HO or Directed Retry

If the mobile is already engaged in Dual Transfer Mode (DTM)

At call establishment if the TCH request is queued

If EN_VAMOS_NON_AMR=FALSE, VAMOS pairing is allowed only for AMR calls

In case of concentric cell:

VAMOS allocation in the inner zone is only allowed on intra-cell HO, when both mobiles candidate for pairing are located in the same zone.

A direct allocation in VAMOS mode in the inner zone is not possible on call establishment, as signal strength values of the Source MS (assigned an SDCCH on the outer zone) & Target MS (already in the inner zone) are not comparable

33


Cell B

VAMOS RADIO ALLOCATION STRATEGY VAMOS PAIRING SCENARIOS : EXAMPLE

MS2

Source MS

Target MSF1, TS 3, TCH-FR

At call establishment: SDCCH sub-channel Not queued No Directed retry

F1, TS 3,

TCH VAMOS-FR

Inter-cell HO: MS2 cannot be source MSCell A

Animated slide:Play in Slide Show mode

CLICK TO PLAY

During inter-cell Handover

No VAMOS allocation

VAMOS pairing during call establishment

(EN_VAMOS_NASS = True)

MS2

VAMOS pairing HO (cause 35)

Source MS

34


VAMOS RADIO ALLOCATION STRATEGY CELL LOAD CRITERIA (1/2)

As in B11, the choice whether a FR or HR channel shall be assigned is based on the load evaluation (among other criteria)

In addition to LOAD_SV1 & LOAD_SV3 levels used for non-VAMOS allocations, new load levels have been defined in B12 for VAMOS allocation:

LOAD_VAMOS_FR: if the cell load increases up to this level, a VAMOS FR subchannel can be allocated to the Source MS (if supported by MS/cell & suitable Target MS can be found)

LOAD_VAMOS_HR: if the cell load still increases up to that level, a VAMOS HR subchannel can be allocated to the Source MS (if supported by MS/cell and if a suitable Target MS can be found)

The following mandatory rules should be respected: LOAD_SV3 LOAD_VAMOS_HR: Given the co-channel interference generated by the paired user,

it doesnt make sense to allow VAMOS-HR allocation before permitting non-VAMOS HR in the cell

LOAD_VAMOS_FR LOAD_VAMOS_HR: Gradual load increase triggers VAMOS-FR allocations before VAMOS-HR allocations (or at least both allocations at the same time)

To allow a hysteresis zone between VAMOS & non-VAMOS allocations, 4 parameters are defined in B12: THR_FR_LOAD_L_VAMOS_FR, THR_FR_LOAD_U_VAMOS_FR,THR_FR_LOAD_L_VAMOS_HR and THR_FR_LOAD_U_VAMOS_HR

35


VAMOS RADIO ALLOCATION STRATEGY CELL LOAD CRITERIA (2/2)

The Cell Load Evaluation is computed as in B11:

Cell load AV_LOAD() computed from Load samples = NB_BUSY_TS / NB_TS * 100 Non sliding window (LOAD_EV_PERIOD) averaging process

Example:

Time

AV_LOAD

THR_FR_LOAD_U_VAMOS_HR

THR_FR_LOAD_U_VAMOS_FR

THR_FR_LOAD_L_VAMOS_HR

THR_FR_LOAD_L_VAMOS_FR

100%

Non-VAMOS allocations

VAMOS-FR allocationsNon-VAMOS HR allocations

VAMOS-FR & VAMOS-HR allocations

Non-VAMOS allocations

VAMOS-FR allocationsNon-VAMOS HR allocations

36


VAMOS RADIO ALLOCATION STRATEGY CELL LOAD CRITERIA CASE 1

LOAD_VAMOS_FR < LOAD_SV3 & LOAD_VAMOS_HR > LOAD_SV1

Pros: Could be beneficial if VAMOS-FR can provide better voice quality than non-VAMOS HR Allows early VAMOS-FR allocation, therefore providing high capacity gains

Cons: Non-VAMOS HR has higher output power than VAMOS-FR due to AQPSK back-off,

accordingly, this scenario will probably cause performance degradation compared to case 3

Cell load

Non-Vamosallocation

Vamosallocation

LOAD_VAMOS_FR

LOAD_VAMOS_HR

LOAD_SV1

LOAD_SV3VAMOS FR

VAMOS HR

Non-VAMOS FR

Non-VAMOS HR SV3

Non-VAMOS HR (SV1 and SV3)

37



LOAD_SV3 < LOAD_VAMOS_FR < LOAD_SV1 & LOAD_VAMOS_HR > LOAD_SV1

Pros:

Compared to case 1, more calls can benefit from high DL transmit powerCons:

Still sub-optimal coverage vs. capacity comprise due to early VAMOS-FR allocations with respect to non-AMR HR

Cell load

Non-Vamosallocation

Vamosallocation

LOAD_VAMOS_FR

LOAD_VAMOS_HR

LOAD_SV1

LOAD_SV3VAMOS FR

VAMOS HR

Non-VAMOS FR

Non-VAMOS HR SV3


38



LOAD_SV1 < LOAD_VAMOS_FR < LOAD_VAMOS_HR

Pros: Best choice to limit AQPS back-off impact: HR allocations have higher precedence than

VAMOS allocations

Cons: Late VAMOS allocation compared to cases 1 & 2, but this could be compensated by HO

Cause 35 (VAMOS_PAIRING_HO)

Cell load

Non-Vamosallocation

Vamosallocation

LOAD_VAMOS_FR

LOAD_VAMOS_HR

LOAD_SV1

LOAD_SV3 VAMOS FR

VAMOS HR

Non-VAMOS FR

Non-VAMOS HR SV3


39



LOAD_VAMOS_FR < LOAD_SV3 & LOAD_SV3 < LOAD_VAMOS_HR < LOAD_SV1

Pros: High capacity gains: VAMOS is allowed very early in the cell

Cons: Early VAMOS allocation increase the impact of AQPS back-off on overall cell coverage Bad speech performance if VAMOS-FR cannot provide better VQ than non-VAMOS HR Sub-optimal capacity usage caused by non-AMR mobiles mostly allocated 1 FR timeslot

Cell load

Non-Vamosallocation

Vamosallocation

LOAD_VAMOS_FR

LOAD_VAMOS_HR

LOAD_SV1

LOAD_SV3 VAMOS FR

VAMOS HR

Non-VAMOS FR

Non-VAMOS HR SV3


40



LOAD_SV3 < LOAD_VAMOS_FR < LOAD_VAMOS_HR < LOAD_SV1

Pros: Trade-off between coverage and capacity

Cons: Sub-optimal capacity usage caused by non-AMR mobiles mostly allocated 1 FR timeslot

Cell load

Non-Vamosallocation

Vamosallocation

LOAD_VAMOS_FR

LOAD_VAMOS_HR

LOAD_SV1

LOAD_SV3VAMOS FR

VAMOS HR

Non-VAMOS FR

Non-VAMOS HR SV3


41


VAMOS RADIO ALLOCATION STRATEGY RADIO CONDITIONS CRITERIA (1/4)

The aim of checking radio conditions criteria is to:

1. Ensure minimum acceptable radio conditions for both users candidate for VAMOS pairing

2. Ensure appropriate radio conditions between both users (i.e. pathloss difference between both users should be within a certain range defined by SCPIRlow & SCPIRhigh values)

The VAMOS user pairing algorithm relies on the AV_RXQUAL_DL_VAMOS_PAIRINGand AV_RXLEV_DL_VAMOS_PAIRING averages computed by the BSC using the DL measurements provided by the Source and Target MSs

Note: UL measurements are not used to reduce the processing effort of the pairing algorithm and because the DL is considered the limiting link for VAMOS

NORM_RXLEV_DL values are used to compute the AV_RXLEV_DL_VAMOS_PAIRING averaged values using the A_LEV_VAMOS_PAIRING averaging window

RXQUAL_DL values are used to compute the AV_RXQUAL_DL_VAMOS_PAIRING averaged values using the A_QUAL_VAMOS_PAIRING averaging window

42



AV_RXLEV_DL_VAMOS_PAIRING is computed based on Normalized RxLev:

NORM_RXLEV_DL is the normalized RXLEV_DL value with respect to the BTS transmitted power, computed as:

NORM_RXLEV_DL = RXLEV_DL + BS_TXPWR

BS_TXPWR: Attenuation with respect to the maximum BTS transmitted power

This normalization allows a fair comparison between RxLev values of different users regardless their different power transmission levels (due to power control etc)

When a Source MS is in the call establishment phase, the averaging is based on the NORM_RXLEV_DL measurements on DL SDCCH & SACCH bursts

If Source & Target MS are already allocated to a TCH in the cell, the averaging is based on NORM_RXLEV_DL & RXQUAL_DL measurements on DL TCH/FACCH & SACCH bursts

43



1. Ensure minimum acceptable radio conditions for both users candidate for VAMOS pairing:

To allow VAMOS pairing of a Source MS with a Target MS, the following conditions must be fulfilled:

AV_RXQUAL_DL_VAMOS_PAIRING < RXQUAL_DL_MAX_VAMOS_PAIRING=> Applicable to Target MS

Note: The RXQUAL criterion is not valid for Source MS because there is a strong possibility that the frequency used for such RXQUAL measurements will change after VAMOS pairing, therefore this information is not relevant for the pairing algorithm

AV_RXLEV_DL_VAMOS_PAIRING > RXLEV_DL_MIN_VAMOS_PAIRING=> Applicable to both the Source MS & Target MS

44



2. Ensure appropriate radio conditions between both users (i.e. path loss difference between both users should be within a certain range defined by SCPIRlow & SCPIRhigh values)

To VAMOS-pair 2 MSs (with MS1 in VAMOS subchannel#1 & MS2 in subchannel#2), their AV_RXLEV_DL_VAMOS_PAIRING values should fulfill the following condition:

SCPIRlow(MS1, MS2) - DELTA_SCPIR_VAMOS_PAIRING AV_RXLEV_DL_VAMOS_PAIRING(MS2) AV_RXLEV_DL_VAMOS_PAIRING(MS1) SCPIRhigh(MS1, MS2) + DELTA_SCPIR_VAMOS_PAIRING

SCPIRlow (MS1, MS2) = SCPIR_LOW_MS_ALLOC_xxx (xxx is MS capability of MS1)SCPIRhigh (MS1, MS2) = - SCPIR_LOW_MS_ALLOC_yyy (yyy is MS capability of MS2)

DELTA_SCPIR_VAMOS_PAIRING is introduced to add flexibility to the pairing algorithm:

If it is set to a positive value, then it will be allowed to VAMOS-pair two MSs having a difference between the DL RXLEV values (in dBm) higher than SCPIRhigh or lower than SCPIRlow, i.e. the two MSs may be in non-optimal radio conditions to be VAMOS-paired together

If it is set to a negative value, then the two MSs shall only be in optimal radio conditions to be paired

45


VAMOS RADIO ALLOCATION STRATEGY MS CAPABILITIES CRITERIA Priorities are set for the different pairing combinations The target is to exploit the best capacity gains from VAMOS pairing:It is preferable to pair a VAMOS-L2 MS with a legacy non-SAIC MS than with a VAMOS-L1

MS, because a legacy non-SAIC MS can only be paired with a VAMOS- L2 MS (i.e. no VAMOS pairing of legacy non-SAIC MS if VAMOS-L2 MS isnt available)

As very few VAMOS MSs will be available on the field at early VAMOS introduction, their pairing with a legacy MS shall have a higher priority than pairing with another VAMOS one

Default priorities are presented below (1: highest priority, 6 = least priority)Such priority rules are configurable by the operator through the parameters PAIRING_PRIORITIES_NON_SAIC , PAIRING_PRIORITIES_SAIC ,PAIRING_PRIORITIES_VAMOS1 and PAIRING_PRIORITIES_VAMOS2

Non-SAIC SAIC VAMOS-1(TSC Set1)VAMOS-1(TSC Set2)

VAMOS-2(TSC Set1)

VAMOS-2(TSC Set2)

PAIRING_PRIORITIES_NON_SAIC 6 6 6 2 6 1

PAIRING_PRIORITIES_SAIC 6 2 6 1 6 3

PAIRING_PRIORITIES_VAMOS_1 6 1 2 3 4 5

PAIRING_PRIORITIES_VAMOS_2 1 2 3 4 5 6

46


VAMOS RADIO ALLOCATION STRATEGY TARGET_MS LIST

This list is created in all VAMOS-supporting cells (where VAMOS is enabled)

Contains all the active MSs of the cell fulfilling ALL the following conditions: MS is allocated into a non-VAMOS channel for a speech call on a VAMOS-capable TRX

MS type is allowed to be paired, based on the flags EN_PAIRING_xxx_yyy

The last AV_RXQUAL_DL_VAMOS_PAIRING < RXQUAL_DL_MAX_VAMOS_PAIRING

The last AV_RXLEV_DL_VAMOS_PAIRING > RXLEV_DL_MIN_VAMOS_PAIRING

The allocated TCH is not in DTM mode or it is in dedicated mode and the N_DELAYED_HO_CAUSE30 is not running

The used codec is AMR or EN_VAMOS_NON_AMR is TRUE

When any of the above conditions is not fulfilled, the MS is removed from the Target_MS list (e.g. call release, radio conditions criteria not satisfied)

The MSs contained in this list are candidate Target MS for VAMOS pairing, and also Source MS in case of VAMOS pairing HO (cause 35)

47


VAMOS RADIO ALLOCATION STRATEGY VAMOS PAIRING PROCESS DESCRIPTION (1/2)

When is VAMOS user pairing algorithm triggered?

When all the following conditions are fulfilled:

VAMOS is enabled in the cell

There are idle VAMOS subchannels in a VAMOS-capable TRX

The cell load criteria for VAMOS allocation is satisfied

There is a Source MS fulfilling the rules described in slide 32, either at call establishment phase or subject to intra-cell HO cause 35 The last AV_RXLEV_DL_VAMOS_PAIRING of the Source MS > RXLEV_DL_MIN_VAMOS_PAIRING

EN_VAMOS_NON_AMR parameter is set to enabled or the Source MS will use an AMR codec

A source MS at call establishment phase is candidate for VAMOS allocation only if EN_VAMOS_NASS = TRUE and RTCH request is not put in queue

Once the user pairing algorithm is triggered, it starts looking for a suitable Target_MS => steps described in the next slide

48


VAMOS RADIO ALLOCATION STRATEGY VAMOS PAIRING PROCESS DESCRIPTION (2/2)

49


VAMOS RADIO ALLOCATION STRATEGY INITIAL SCPIR COMPUTATION (1/2)

SCPIR is set according to the MS capabilities and radio conditions

For a (legacy SAIC, legacy SAIC) pair, when the parameter EN_SAIC_SCPIR_MODIF is set to False, then DL SCPIR shall remain at 0 dB

Given that MS1 is allocated on VAMOS sub-channel1 & MS2 on sub-channel2 Case 1: DELTA_SCPIR_VAMOS_PAIRING > 0 => Initial DL SCPIR (MS1, MS2) is

computed as follows:

L2 L1

SCPIRlow

SCPIRlow

SCPIRlow + (SCPIRhigh-SCPIRlow)/2

SCPIRhigh

Initial SCPIR

L1 = last AV_RXLEV_DL_VAMOS_PAIRING value of the user to be allocated in subchannel#1

L2 = last AV_RXLEV_DL_VAMOS_PAIRING value of the user to be allocated in the subchannel#2

DELTA = DELTA_SCPIR_VAMOS_PAIRING

SCPIRhigh SCPIRhigh + DELTASCPIRlow - SCPIRlow + (SCPIRhigh -DELTA SCPIRlow)/2

50


VAMOS RADIO ALLOCATION STRATEGY INITIAL SCPIR COMPUTATION (2/2)

Case 2: DELTA_SCPIR_VAMOS_PAIRING 0 => Initial DL SCPIR (MS1, MS2) is equal to L2-L1

L1 = last AV_RXLEV_DL_VAMOS_PAIRING value of the user to be allocated in subchannel#1

L2 = last AV_RXLEV_DL_VAMOS_PAIRING value of the user to be allocated in the subchannel#2

DELTA = DELTA_SCPIR_VAMOS_PAIRING

L2 L1

SCPIRlow - DELTA

SCPIRlow + (SCPIRhigh-SCPIRlow)/2

SCPIRhigh + DELTA

Initial SCPIR

SCPIRhigh + DELTA

SCPIRlow -DELTA

SCPIRlow + (SCPIRhigh -SCPIRlow)/2

SCPIRhighSCPIRlow

51


VAMOS RADIO ALLOCATION STRATEGY INITIAL POWER COMPUTATION OF SOURCE MS

VAMOS pairing @ intra-cell handover: The MS power of the handed-over MS (the Source MS) shall be kept equal to the last used value

VAMOS pairing @ call establishment: The BSS uses the difference between the AV_RXLEV_DL_VAMOS_PAIRING averaged measurements, used to compute the initial DL SCPIR, to compute the initial MS power of the Source MS:

Initial MS_power of Source MS = Roundup ( MS_power [Target MS] + (AV_RXLEV_DL_VAMOS_PAIRING [Target MS] AV_RXLEV_DL_VAMOS_PAIRING [Source MS]) )

Target MS keeps its power equal to the last used value when it is VAMOS-paired, it can be changed later-on based on UL power control mechanisms

52


1.4 | NEW HO CAUSES IN VAMOS


53


NEW HO CAUSES IN VAMOS VAMOS UNPAIRING HO (CAUSE 34) Occurs due to too bad radio quality for a VAMOS subchannel, leading to intra-cell

handover of one of the paired users from a VAMOS channel to another channel (either VAMOS or non-VAMOS) when EN_VAMOS_UNPAIRING_CA = TRUE

The codec type (FR, HR) remains the same after unpairing Condition: For one user of the VAMOS pair,

AV_RXQUAL_DL_VAMOS_UNPAIRING > RXQUAL_DL_MIN_VAMOS_UNPAIRING, or AV_RXLEV_DL_VAMOS_UNPAIRING < RXLEV_DL_MAX_VAMOS_UNPAIRINGNew window sizes: A_LEV_VAMOS_UNPAIRING & A_QUAL_VAMOS_UNPAIRING

Result: Only one user of the VAMOS pair is handed-over: the one reporting better quality and/or higher signal level measurements (to avoid call drop/HO failure of the user suffering from bad radio conditions)

Benefits on the remaining user: higher transmit power in GSMK and no more co-channel interference from the paired user

If both paired MSs fulfill the unpairing conditions, with similar RxQual/RxLev average measurements, the user on sub-channel 2 is handed-over to another channel

When the MS is unpaired and allocated on a non-VAMOS channel, then the timer MIN_TIME_BTW_VAMOS_PAIRING is launched to define the frequency by which HOP shall try a VAMOS pairing algorithm on that MS

54


NEW HO CAUSES IN VAMOS VAMOS PAIRING HO (CAUSE 35)

Occurs in case of high signal level and high load for VAMOS pairing, leading to intra-cell handover of one user from a non-VAMOS channel to a VAMOS channel

The codec type (FR or HR) remains the same after pairing

Concerns the MSs allocated to a non-VAMOS channel, when all the below conditions are fulfilled:

EN_VAMOS_PAIRING_CA = TRUE AV_RXLEV_DL_VAMOS_PAIRING > RXLEV_DL_MIN_VAMOS_PAIRING

Cell load conditions for VAMOS allocation are fulfilled

The timer MIN_TIME_BTW_VAMOS_PAIRING has expired for that MSAveraging window sizes: A_LEV_VAMOS_PAIRING & A_QUAL_VAMOS_PAIRING

If that Source_MS cannot be allocated on a VAMOS subchannel because no suitable Target MS can be found, this MS keeps its current non-VAMOS channel and the timer MIN_TIME_BTW_VAMOS_PAIRING is launched for this MS (to avoid triggering this HO cause immediately for that MS)

55


NEW HO CAUSES IN VAMOS OTHER HO CAUSES

All the B11 HO causes will apply also to VAMOS-paired MSs

Only Fast Traffic HO (cause 28) is impacted by VAMOS: A resource allocated in VAMOS mode is not candidate for Fast Traffic HO to another cell,

because a queued request cannot be allocated in VAMOS mode A MS included in the Target MSs list is not candidate for Fast Traffic HO

It is not planned to define a specific intra-cell HO just to change the TSC of an existing user

HO cause priorities: A VAMOS unpairing handover cause 34 has a higher priority than the HR-to-FR channel

adaptation cause 26 and emergency intra-cell interference HOs (cause 15 & 16)

A VAMOS pairing handover cause 35 has a lower priority than the FR-to-HR channel adaptation cause 27 (to allow a FR call to be allocated in a non-VAMOS HR channel if such channel is available) and PBGT HO cause 12

Emergency HO causes 27 have higher priority than VAMOS intra-cell HO cause 34, but the trigger condition of cause 34 might be usually reached before causes 4 & 5 (due to shorter averaging window size and lower threshold values for cause 34)

56


NEW HO CAUSES IN VAMOS INTERACTION BETWEEN DIFFERENT HO CAUSES

AV_LOAD

Example: A FR call started in non-VAMOS mode, assuming a user in mobility on a highway between 2 sites with the below Avg_RxLev/Traffic_load relationship

AV_DLRxLev-45 dBm

RXLEV_DL_MIN_VAMOS_PAIRING

RXLEV_DL_MAX_VAMOS_UNPAIRING

L_RXLEV_DL_H

Intra-cell HO cause 35

Call started: Non-VAMOS channel (Load condition not fulfilled)

VAMOS unpairing HO cause 34 (bad signal strength)

-110 dBm Inter-cell HO cause 5

Possible VAMOS pairing HO 35 in the new cell


Note: Different averaging window size for VAMOS pairing, unpairing and emergency HO

57


1.5 | POWER CONTROL STRATEGY


58


VAMOS POWER CONTROL STRATEGY POWER CONTROL APPROACH

Power Control handles the adaptive control of RF transmit power of the MS & BTS

Goals: Minimize the co-channel interference Reduce the DC power consumption of the BTS and MS

VAMOS power control is based on RxQual & RxLev averaged measurements Initial SCPIR having been optimally chosen during VAMOS pairing phase (based on MS

capabilities of paired users), SCPIR is then changed reactively based on RxQual values:

In case of RXQUAL degradation experienced by a VAMOS user, the VAMOS DL Power Control process will react increasing its power level with respect to the power level of the paired VAMOS user by modifying the SCPIR to favor the degraded user

The operator can choose different SCPIR constraints SCPIR_LOW_MS_PC_xxx for VAMOS Power Control algorithm than the SCPIR constraints of the VAMOS Radio Allocation procedure SCPIR_LOW_MS_ALLOC_xxx e.g. very strict SCPIR constraints for the radio allocation procedure to minimize unpairing

possibilities - and smoother constraints for the power control algorithm with reactive SCPIR update based on RxQual

59


VAMOS POWER CONTROL STRATEGY RECALL OF NON-VAMOS POWER CONTROL Power decrease happens when:

Too good quality & fair signal level: Average Quality < U_RXQUAL_xL_P ANDAverage Rxlev >= L_RXLEV_xL_P + POW_RED_STEP_SIZE or,

Too good level & fair quality: Average Rxlev > U_RXLEV_xL_P ANDU_RXQUAL_xL_P Average Quality < L_RXQUAL_xL_P + OFFSET_HOPPING_PC

Power increase happens when:

Average Quality > L_RXQUAL_xL_P + OFFSET_HOPPING_PC (*)

OrAverage Quality

60


VAMOS POWER CONTROL STRATEGY VAMOS DL POWER CONTROL

3 zones are identified depending on the averaged RXQUAL and RXLEV values:

In VAMOS mode, L_RXLEV_DL_P_VAMOS, U_RXLEV_DL_P_VAMOS andL_RXQUAL_DL_P_VAMOS replace L_RXLEV_DL_P, U_RXLEV_DL_P andL_RXQUAL_DL_P respectively

For simplicity, the parameter U_RXQUAL_DL_P is not supported by the VAMOS DL PC process (i.e. no differentiation between PC-2 & PC-4 zones of previous slide)

New averaging window size parameters are defined for VAMOS: A_LEV_PC_VAMOS & A_QUAL_PC_VAMOS to allow more reactivity to radio condition variations than B11 PC

L_RXQUAL_DL_P_VAMOS

i = 1 or 2 (VAMOS subchannel number)

Ai

Bi Ci

RXQUAL_i

RXLEV_iL_RXLEV_DL_P_VAMOS U_RXLEV_DL_P_VAMOS

0

7

Zone A: bad quality or/and low level

Zone B: good quality and good level

Zone C: good quality and too high level

61


VAMOS POWER CONTROL STRATEGY VAMOS DL POWER CONTROL - RULES The BTS cannot transmit with a power higher than powermax_AQPSK AQPSK power increase is performed when at least one user is in the zone A (but only if

the constraint on the maximum transmitted power allows it) AQPSK power decrease is performed when at least one user is in the zone C (but only

if the other user is not in the zone A) Power increase/decrease is applied to both users of the VAMOS pair, since there is only

1 physical AQPSK power No VAMOS Power Control when both users are in the zone B

SCPIR modification SCPIR modification without AQPSK power modification stands for a modification of the

power ratio between the users while keeping a constant AQPSK power level

SCPIR modification is always performed when the 2 users are in different zones(except when the new SCPIR value would be out of the allowed range) to favor a user in the zone A and/or to penalize a user in the zone C. The SCPIR modification can be performed on top of the AQPSK power increase /decrease when one user is in the zone A or C

For a (legacy SAIC, legacy SAIC) pair, when EN_SAIC_SCPIR_MODIF = False, then the DL SCPIR value is fixed to 0dB and only the AQPSK power can be modified

62


VAMOS POWER CONTROL STRATEGY VAMOS DL POWER CONTROL COMMANDS (1/2)

1. PC_COMMAND (BS, INC, BS_P_INC, < powermax):

Increase BS_TXPWR_1 and BS_TXPWR_2 by min (BS_P_INC, MAX_POW_INC_VAMOS, powermax - BS_TXPWR), where BS_P_INC = max (BS_P_INC_1, BS_P_INC_2)

BS_P_INC_i is evaluated using the same approach as in non-VAMOS case:

If (AV_RXLEV_DL_PC_VAMOS_i < L_RXLEV_DL_P_VAMOS) (Signal strength problem)

If (AV_RXQUAL_DL_PC_VAMOS_i L_RXQUAL_DL_P(_AMR_RxACCH)_VAMOS + OFFSET_RXQUAL_FH) (good quality)

then BS_P_INC_i = roundup [POW_INC_FACTOR_VAMOS x(TARGET_RXLEV_DL - AV_RXLEV_DL_PC_VAMOS_i)]

Else BS_P_INC_i = roundup [MAX (POW_INC_FACTOR_VAMOS x(TARGET_RXLEV_DL - AV_RXLEV_DL_PC_VAMOS_i), POW_INC_STEP_SIZE_VAMOS)]

Else (Quality problem)BS_P_INC_i = POW_INC_STEP_SIZE_VAMOS

TARGET_RXLEV_DL = (U_RXLEV_DL_P_VAMOS + L_RXLEV_DL_P_VAMOS)/2

63


VAMOS POWER CONTROL STRATEGY VAMOS DL POWER CONTROL COMMANDS (2/2)

2. PC_COMMAND (BS, RED, BS_P_RED, > powermin):

Decrease BS_TXPWR_1 and BS_TXPWR_2 by min (BS_P_RED, MAX_POW_RED_VAMOS, BS_TXPWR powermin) where BS_P_RED = min (BS_P_RED_1, BS_P_RED_2)

BS_P_RED_i is evaluated using the same approach as in non-VAMOS case:

If (AV_RXLEV_DL_PC_VAMOS_i > U_RXLEV_DL_P_VAMOS)

Then BS_P_RED_i = rounddown [MAX (POW_RED_FACTOR_VAMOS x (AV_RXLEV_DL_PC_VAMOS_i - TARGET_RXLEV_DL), POW_RED_STEP_SIZE_VAMOS)]

Else BS_P_RED_i = POW_RED_STEP_SIZE_VAMOS

3. PC_COMMAND (SCPIR, INC, SCPIR_MODIF_STEP_SIZE, = SCPIRlow_PC):SCPIRnew = MAX (SCPIRold SCPIR_MODIF_STEP_SIZE, SCPIRlow_PC) keeping same BS_TXPWR

64


VAMOS POWER CONTROL STRATEGY VAMOS DL POWER CONTROL CAUSES (1/3)1. Too bad quality or/and too low level for both users (PC-A1A2):

Both user powers shall be increased without modifying the SCPIR

=> PC_COMMAND (BS, INC, BS_P_INC, < powermax_AQPSK)

2. Too bad quality or/and too low level for user1 & good quality/level for user2 (PC-A1B2):

Both user powers are increased and then the SCPIR is increased to favor user 1=> PC_COMMAND (BS, INC, BS_P_INC,

65


VAMOS POWER CONTROL STRATEGY VAMOS DL POWER CONTROL CAUSES (2/3)4. Good quality and level for user1 & too bad quality or/and too low level for user2

(PC-B1A2):

Both user powers are increased and then the SCPIR is increased to favor user 2=> PC_COMMAND (BS, INC, BS_P_INC, = SCPIRlow_PC)

5. Good quality and level for both users (PC-B1B2):

No power control is applied

6. Good quality/level for user1 & too high level for user2 (PC-B1C2):

Both user powers are decreased and then the SCPIR is increased to favor user 1=> PC_COMMAND (BS, RED, BS_P_RED, > BS_TXPWR_MIN)and PC_COMMAND (SCPIR, INC, SCPIR_MODIF_STEP_SIZE,

66


VAMOS POWER CONTROL STRATEGY VAMOS DL POWER CONTROL CAUSES (3/3)7. Too high level for user1 & too bad quality or/and too low level for user2

(PC-C1A2):

Both user powers are increased and then the SCPIR is reduced to favor user 2=> PC_COMMAND (BS, INC, BS_P_INC, = SCPIRlow_PC)

8. Too high level for user1 & good quality/level for user2 (PC-C1B2):

Both user powers are decreased and then the SCPIR is reduced to favor user 2=> PC_COMMAND (BS, RED, BS_P_RED, > BS_TXPWR_MIN)and PC_COMMAND (SCPIR, RED, SCPIR_MODIF_STEP_SIZE, >= SCPIRlow_PC)

9. Too high level for both users (PC-C1C2):

Both user powers shall be decreased

=> PC_COMMAND (BS, RED, BS_P_RED, > BS_TXPWR_MIN)

67


VAMOS POWER CONTROL STRATEGY VAMOS DL POWER CONTROL GENERAL HINTS

At VAMOS pairing/unpairing, the BSC stops the BS PC algorithms for the paired MS during a period defined by T_INHIBIT_VAMOS_PC, this timer guarantees that:

The BSC has enough time to receive the DL measurement results from both paired MSs following VAMOS pairing

The BSC has enough time to receive the first DL measurement results in non-VAMOS mode performed by the remaining MS, following VAMOS unpairing

When DL DTX is enabled, during a speech pause of one of the paired users, legacy GMSK is used for the other user if it is in a speech period; while AQPSK must be used when SID frames are transmitted

Those GMSK bursts are transmitted with the power level computed by the BSC as if they were AQPSK bursts

When a SACCH/FACCH frame for one user in a VAMOS pair is multiplexed with a TCH frame for the paired user (e.g. shifted SACCH technique is used, valid for VAMOS-L2 using TSC set2), the BTS modifies the SCPIR to favor the user transmitting the FACCH/SACCH frame. This SCPIR modification shall be equal to the SCPIR_MODIF_VAMOS_CCCH parameter value

68


VAMOS POWER CONTROL STRATEGY VAMOS UL POWER CONTROL (1/2)

Goal: Reach an ideal UL signal level detected in the BTS, allowing correct signal decoding Measured UL RXLEV in VAMOS mode: is the total received signal (subchannel#1 +

subchannel#2) measured at the antenna connector => The 2 UL RXLEV values will be equal, the BTS cant measure a different UL RXLEV value for each of the 2 VAMOS subchannels.The MS Power Control commands in VAMOS mode are based on the UL RXQUAL measurements for each of the 2 GMSK signals and on the total received signal

Approach: In order to avoid an increase of UL interference in the network, UL PC process tries to have the same level for the 2 UL VAMOS signals, even if the BTS cannot measure it.Then, to react to bad RxQual of one of the 2 MSs, increasing the MS power should be controlled in order to keep the difference between the 2 UL VAMOS signals within a specific range (otherwise, decoding of one of these signals will become impossible). Thus, if the maximum allowed MS power difference is reached with still bad UL_RXQUAL of one user, the BSS shall stop increasing the MS power and trigger a handover.

How: For simplicity, it is assumed that DL path loss is similar to UL path loss (i.e., the requested difference between MS1 & MS2 UL transmitted powers should be similar to DELTA_DLRXLEV):

DELTA_DLRXLEV = [AV_RXLEV_DL_PC_VAMOS_2 AV_RXLEV_DL_PC_VAMOS_1]

69


VAMOS POWER CONTROL STRATEGY VAMOS UL POWER CONTROL (2/2) How (cont.):

Whenever MS Power Control algorithm implies a modification of MS_TXPWR_1 and/or MS_TXPWR_2, the BSC applies the below rule:

MS_TXPWR_1 - MS_TXPWR_2 should be in the range:[DELTA_DLRXLEV - UL_VAMOS_PC_CORRECTION_FACTOR, DELTA_DLRXLEV + UL_VAMOS_PC_CORRECTION_FACTOR]

DELTA_DLRXLEV = AV_RXLEV_DL_PC_VAMOS_2 AV_RXLEV_DL_PC_VAMOS_1

UL_VAMOS_PC_CORRECTION_FACTOR is a correction factor to introduce some flexibility, taking into account the fact that this rule is based on a simplification and that the BTS has better decoding capabilities than a MS. Its value is a tradeoff between interference and unpairing probability: A low value reduces the allowed range in MS power difference but increases unpairing probability

Similar to the BS PC process, the T_INHIBIT_VAMOS_PC timer is used to stop the MS Power Control process during a VAMOS pairing and a VAMOS unpairing

2 new parameters are used by UL PC process in VAMOS mode: L_RXLEV_UL_P_VAMOS & U_RXLEV_UL_P_VAMOS. Their default value are 3dB higher than the default values of L_RXLEV_UL_P & U_RXLEV_UL_P respectively (since the measured UL signal is the sum of both subchannels)

70


1.6 | SAIC MS ISSUES IN VAMOS MODE


71


SAIC MS ISSUES IN VAMOS MODE NOTIFICATION ISSUE (1/2)

SAIC capability is release independent, indicated by MS CLASSMARK3 Information Element (IE)

Problem description: Some mobile dont report their real voice SAIC capability As SAIC performance requirements are more complex for data services than voice services,

many SAIC mobiles are designed to cope with SAIC voice requirements but not for data

Consequence: Such MSs dont declare themselves as SAIC-capable in Classmark3 IE => Wrong information acquired by the BSS about the SAIC capabilities for voice services => These MSs are managed as non-SAIC MSs! => Thus, they cant be paired to SAIC or VAMOS-1 MSs but only to VAMOS-2 MSs (i.e. less chances to be paired, restricted SCPIR range and increased interference probability)

This notification issue is present in most Nokia SAIC handsets as well as SAIC mobiles based on Qualcomm chipsets

ALU workaround: Test those non-SAIC MSs already having a call established in non-VAMOS mode (and present in Target MSs list) by sending AQPSK bursts - during four 26-frame multiframes (4x120ms) - superposed to the information intended to the MS

72


SAIC MS ISSUES IN VAMOS MODE NOTIFICATION ISSUE (2/2)

ALU workaround (cont.):

Accordingly, an MS cannot be directly allocated a VAMOS channel at TCH establishment even if load condition is fulfilled, but it can be inserted into Target MSs list and marked as To be tested

Cell load >= LOAD_VAMOS_FR threshold

Test MS

Normal GMSK bursts

AQPSK bursts (1 SACCH mf)

Normal burst Dummy burst

Meas. reportMeas. reportMeas. reportMeas. report

Check RxQual_DL in the 4 consecutive reporting periods:- Any RxQual >= 6? => Non SAIC MS

- Otherwise, SAIC MS

1 message for each To be

tested mobile

MS BTS BSC

[Back]

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SAIC MS ISSUES IN VAMOS MODE PERFORMANCE ISSUE

Some SAIC mobiles (Nokia, Qualcomm-based, some blackberries) suffer from bad performance in VAMOS mode:

Call drop after several minutes

Such mobiles require SCPIR > 0, otherwise, RxQual will degrade gradually until call drop

According to Nokia, SCPIR = 0 + DL DTX activation can minimize the issue in parallel with more reactive Power Control settings

A solution based on a black-list of "substandard SAIC MSs" is under evaluation

SAIC-VAMOS1 pair, SCPIR = 0

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SAIC MS ISSUES IN VAMOS MODE PERFORMANCE ISSUE

ALU recommendation:

DL DTX activation is mandatory

SCPIR_LOW_MS_ALLOC_SAIC default value = -2 => allows fast recovery of RxQualdegradation in case of bugged SAIC mobile

SCPIR_LOW_MS_PC_SAIC default value = -4 => to exploit the full SCPIR range of non-bugged SAIC mobiles, BUT it still could be risky for bugged mobiles (to be confirmed by ALU tests)

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6 | CONCLUSION


3 | TEST STRATEGY



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2.1 | VAMOS ACTIVATION


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FEATURE ACTIVATION STRATEGYVAMOS Activation

This feature is activated at cell level

The feature can be activated through the EN_VAMOS telecom parameter EN_VAMOS= 0 or 1 / 0 (disabled)

VAMOS can be allowed at the following mobile stations levels through a set of 8 telecom parameters:

1. For the Legacy non-SAIC VAMOS Level 1 pairs: EN_PAIRING_NON_SAIC_VAMOS1

2. For the Legacy non-SAIC VAMOS Level 2 pairs: EN_PAIRING_NON_SAIC_VAMOS2

3. For the Legacy SAIC Legacy SAIC pairs: EN_PAIRING_SAIC_SAIC

4. For the Legacy SAIC VAMOS Level 1 pairs: EN_PAIRING_SAIC_VAMOS1

5. For the Legacy SAIC VAMOS Level 2 pairs: EN_PAIRING_SAIC_VAMOS2

6. For the VAMOS Level 1 VAMOS Level 1 pairs: EN_PAIRING_VAMOS1_VAMOS1



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FEATURE ACTIVATION STRATEGYVAMOS Activation

Feature optionality The VAMOS feature is optional for the network.

Sold by counting the number of TRX

Feature availability This feature is available starting with B12.1 release

Feature recommendations: In B12 ALU BSS VAMOS will be allowed in IP transport only (IPoEth or IPoE1)

The following features should be enable (but not mandatory) in order to enhance VAMOS operation:

DTX

Repeated SACCH/FACCH

AMR

DL Power Control

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2.2 | HW SUPPORT


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FEATURE ACTIVATION STRATEGYHW Support

The following is required by product management for hardware support:

BTS: A9100 (EVOLIUM standard) and SUMA and SUMXSUMP, A9110-E (M5M), A9110 (M4M) dont support VAMOS operation

TRE: G5 TRE (TWIN) and G6 TRE(MC-TRE and MC-RRH)G3(GPRS only) & G4(GPRS & EDGE) TRX dont support VAMOS operation

BSC generation: Evolution BSC (Mx) with TPV1/TPV3G2 BSC doesnt support VAMOS operation

TC: TRAU G2.5 (with MT120) or (with MT120-WB)TRAU G2(MT120/DT16) doesnt support VAMOS operation

O&M: OMC-R and NPOPOLO and OEF dont support VAMOS operation

MFS: not impacted

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FEATURE ACTIVATION STRATEGYHW Support

MC_Module compatibility: The number of TRX supporting VAMOS on a MC-Module is limited due to

processing issues, DSP capacity in the BTS.

This limitation is managed in a static way. BTS gives to the BSC the VAMOS capability for every TRX. This information is an input for TRX/RSL mapping and resource allocation.

Cell Topology compatibility: VAMOS is supported on all cell topologies

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2.3 | NEW VAMOS PARAMETERS


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FEATURE ACTIVATION STRATEGY NEW VAMOS TELECOM PARAMETERS (1/12)

Parameter Name Definition

Sub-System

Instance

Category/ OMC-R access

TypeRange/ Default value

EN_VAMOS Enables / disables VAMOS in the cell BSC Cell Site (CAE)/ Changeable Flag0 or 1 / 0 (disabled)

EN_PAIRING_NON_SAIC_VAMOS1

When VAMOS is activated, enables or disables pairing between Non-SAIC and VAMOS1 MSs BSC Cell Site (CAE)/ Changeable Flag

0 or 1 / 0 (disabled)

EN_PAIRING_NON_SAIC_VAMOS2

When VAMOS is activated, enables or disables pairing between Non-SAIC and VAMOS2 MSs BSC Cell Site (CAE)/ Changeable Flag

0 or 1 / 1 (enabled)

EN_PAIRING_SAIC_SAIC

When VAMOS is activated, enables/ disables pairing between SAIC MSs BSC Cell

Site (CAE)/ Changeable Flag


EN_PAIRING_SAIC_VAMOS1

When VAMOS is activated, enables or disables pairing between SAIC and VAMOS1 MSs BSC Cell Site (CAE)/ Changeable Flag


EN_PAIRING_SAIC_VAMOS2

When VAMOS is activated, enables or disables pairing between SAIC and VAMOS2 MSs BSC Cell Site (CAE)/ Changeable Flag


EN_PAIRING_VAMOS1_VAMOS1

When VAMOS is activated, enables or disables pairing between VAMOS1 MSs BSC Cell Site (CAE)/ Changeable Flag


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Sub-System

Instance


Type Range/ Default value


When VAMOS is activated, enables or disables pairing between VAMOS1 and VAMOS2 MS BSC Cell




When VAMOS is activated, enables or disables pairing between VAMOS2 MSs BSC Cell



EN_VAMOS_NASS

When VAMOS is activated, enables or disables pairing on Normal Assignment BSC Cell



EN_VAMOS_NON_AMR

When VAMOS is activated, enables or disables pairing of calls using non-AMR codecs BSC Cell



EN_SAIC_SCPIR_MODIF

When VAMOS is activated and the pairing between SAIC MSs is enabled, enables/disables SCPIR values different from 0 dB

BSC Cell Site (CAE)/ Changeable Flag0 or 1 / 0 (disabled)

TSC_1_2

When VAMOS is activated, this parameter represents the two Training Sequence Codes (TSC_1, TSC_2) that can be used for any circuit channel established in VAMOS mode; TSC_1 is always used when a circuit channel is established in Non-VAMOS mode

BSC Cell Site (CAE)/ Changeable

Enumerated

0: (0, 5)1: (1, 7)2: (2, 6)3: (3, 4)4: (4, 2)5: (5, 1)6: (6, 3)7: (7, 0)8 to 15: reserved

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Sub-System

Instance



THR_FR_LOAD_L_VAMOS_FR

Lower load threshold to accept VAMOS allocation in FR BSC Cell

Site (CAE)/ Changeable

Threshold

0 to 100 / 100(%)


Higher load threshold for VAMOS allocation in FR BSC Cell Site (CAE)/ ChangeableThreshold

0 to 100 / 100(%)

THR_FR_LOAD_L_VAMOS_HR

Lower load threshold to accept VAMOS allocation in HR BSC Cell

Site (CAE)/ Changeable

Threshold

0 to 100 / 100(%)

THR_FR_LOAD_U_VAMOS_HR

Higher load threshold for VAMOS allocation in HRBSC Cell Site (CAE)/ Changeable

Threshold

0 to 100 / 100(%)

SCPIR_LOW_MS_ALLOC_NON_SAIC

Minimum value of SCPIR allowing a correct decoding of the signal for a Legacy non-SAIC capable MS, allocated to VAMOS sub-channel #1. It is used by the resource allocation algorithm

BSC Cell Site (CAE)/ Changeable Number-10 to 10 / 8 (dB)

SCPIR_LOW_MS_ALLOC_SAIC

Minimum value of SCPIR allowing a correct decoding of the signal for a Legacy SAIC capable MS, allocated to the VAMOS sub-channel #1. It is used by the resource allocation algorithm

BSC Cell Site (CAE)/ Changeable Number-10 to 10 / -2 (dB)

SCPIR_LOW_MS_ALLOC_VAMOS1

Minimum value of SCPIR allowing a correct decoding of the signal for a VAMOS-1 capable MS, allocated to the VAMOS sub-channel #1. It is used by the resource allocation algorithm


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Sub-System

Instance



SCPIR_LOW_MS_ALLOC_VAMOS2

Minimum value of SCPIR allowing a correct decoding of the signal for a VAMOS-2 capable MS, allocated to the VAMOS sub-channel #1. It is used by the resource allocation algorithm

BSC Cell Site (CAE)/ Changeable Number-10 to 10 / -10(dB)

SCPIR_LOW_MS_PC_NON_SAIC

Minimum value of SCPIR allowing a correct decoding of the signal for a Legacy non-SAIC capable MS, allocated to the VAMOS sub-channel #1. It is used by the power control algorithm


SCPIR_LOW_MS_PC_SAIC

Minimum value of SCPIR allowing a correct decoding of the signal for a Legacy SAIC capable MS, allocated to the VAMOS sub-channel #1. It is used by the power control algorithm


SCPIR_LOW_MS_PC_VAMOS1

Minimum value of SCPIR allowing a correct decoding of the signal for a VAMOS-1 capable MS, allocated to the VAMOS sub-channel #1. It is used by the power control algorithm


SCPIR_LOW_MS_PC_VAMOS2

Minimum value of SCPIR allowing a correct decoding of the signal for a VAMOS-2 capable MS, allocated to the VAMOS sub-channel #1. It is used by the power control algorithm

BSC Cell Site (CAE)/ Changeable Number-10 to 10 / -10(dB)

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Sub-System

Instance



L_RXLEV_DL_P_VAMOS

Lower DL level threshold for VAMOS BS power control BSC Cell

Site (CAE)/ Changeable Threshold

-110 to -47-85(dBm)

U_RXLEV_DL_P_VAMOS

Upper DL level threshold for VAMOS BS power control BSC Cell


-110 to -47 -75(dBm)

L_RXLEV_UL_P_VAMOS

Lower uplink level threshold for VAMOS MS power control BSC Cell


-110 to -47 / -87 (dBm)

U_RXLEV_UL_P_VAMOS

Upper uplink level threshold for VAMOS MS power control BSC Cell


-110 to -47 / -72 (dBm)

L_RXQUAL_DL_P_VAMOS

Lower downlink quality threshold for VAMOS power control (all VAMOS calls except AMR-NB / AMR-WB ones where repeated DL FACCH / SACCH are activated)

BSC Cell Site (CAE)/ Changeable Threshold 0 to 7 / 3

L_RXQUAL_DL_P_AMR_RXACCH_VAMOS

Lower downlink quality threshold for VAMOS power control for VAMOS calls with AMR-NB / AMR-WB ones where repeated DL FACCH / SACCH are activated)

BSC Cell Site (CAE)/ Changeable Threshold 0 to 7 / 3

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Sub-System

Instance



MAX_POW_INC_VAMOS

Maximum Power increase of a VAMOS sub-channel in one power command BSC Cell

Site (CAE)/ Changeable Number

2 to 16 / 8 (dB)

MAX_POW_RED_VAMOS

Maximum Power decrease of a VAMOS sub-channel in one power command BSC Cell


2 to 16 / 8 (dB)

POW_INC_FACTOR_VAMOS

VAMOS weighting factor for power increase BSC Cell Site (CAE)/ Changeable Number0 to 1 / 0.8

POW_INC_STEP_SIZE_VAMOS

Power increase step size of a VAMOS sub-channel in case of power command triggered on quality criterion

BSC Cell Site (CAE)/ Changeable Number2 to 14 / 6 (dB)

POW_RED_FACTOR_VAMOS

VAMOS weighting factor for power decrease BSC Cell


0 to 1 / 0.5

POW_RED_STEP_SIZE_VAMOS

Power reduction step size of a VAMOS sub-channel in case of power command triggered on quality criterion

BSC Cell Site (CAE)/ Changeable Number2 to 4 / 2 (dB)

SCPIR_MODIF_STEP_SIZE

SCPIR step size for increase or reduction BSC Cell Site (CAE)/ Changeable Flag0 to 20 / 2 (dB)

A_LEV_PC_VAMOS

Window size for level average for VAMOS PC BSC Cell


1 to 31 / 4

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Sub-System

Instance



W_LEV_PC_VAMOS

Weight applicable to level samples for VAMOS power control when no DTX is applied

BSC Cell Site (CAE)/ Changeable Number 1 to 3 / 1

A_QUAL_PC_VAMOS

Window size for quality average for VAMOS PC BSC Cell


1 to 31 / 4

W_QUAL_PC_VAMOS

Weight applicable to quality samples for VAMOS power control when no DTX is applied


A_LEV_ VAMOS_PAIRING

Window size for level average for VAMOS pairing BSC Cell


1 to 31 / 5

A_LEV_ VAMOS_UNPAIRING

Window size for level average for VAMOS unpairing BSC Cell


1 to 31 / 3

A_QUAL_ VAMOS_PAIRING

Window size for quality average for VAMOS pairing BSC Cell


1 to 31 / 5

A_QUAL_ VAMOS_UNPAIRING

Window size for quality average for VAMOS unpairing BSC Cell


1 to 31 / 3

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Sub-System

Instance



RXLEV_DL_MIN_VAMOS_PAIRING

Minimum averaged level value allowing VAMOS pairing BSC Cell


-110 to -17 / -75 (dBm)

RXQUAL_DL_MAX_VAMOS_PAIRING

Maximum averaged quality value allowing VAMOS pairing BSC Cell

Site (CAE)/ Changeable Threshold 0 to 7 / 1

DELTA_SCPIR_VAMOS_PAIRING

Maximum deviation on the difference between averaged level values of two MSs allowing them to be VAMOS-paired on the same TCH


RXLEV_DL_MAX_VAMOS_UNPAIRING

Maximum averaged level value allowing VAMOS unpairing BSC Cell Site (CAE)/ Changeable Threshold

-110 to -47 / -

90 (dBm)

RXQUAL_DL_MIN_VAMOS_UNPAIRING

Minimum averaged quality value allowing VAMOS unpairing BSC Cell Site (CAE)/ Changeable Threshold 0 to 7 / 4

MIN_TIME_BTW_VAMOS_PAIRING

Minimum time to wait for a CS call before a new pairing attempt after a failed pairing attempt or after an unpairing

BSC Cell Site (CAE)/ Changeable Timer1 to 10 /

1 (second)

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Sub-System

Instance



W_LEV_ VAMOS_PAIRING

Weight applicable to level samples for VAMOS pairing when DTX is disabled or when DTX is enabled and no silence period is present in the multiframe


W_QUAL_ VAMOS_PAIRING

Weight applicable to quality samples for VAMOS pairing when DTX is disabled or when DTX is enabled and no silence period is present


W_LEV_ VAMOS_UNPAIRING

Weight applicable to level samples for VAMOS unpairing when DTX is disabled or when DTX is enabled and no silence period is present


W_QUAL_ VAMOS_UNPAIRING

Weight applicable to quality samples for unpairing when DTX is disabled or when DTX is enabled and no silence period is present


SCPIR_MODIF_VAMOS_CCCH

Power increase for FACCH and SACCH frames BSC Cell


0 to 4 / 0 [dB]

EN_TEST_FOR_NON_SAIC

When VAMOS is activated, enable/disable the transmission of AQPSK test bursts for non-SAIC MSs

BSC Cell Site (CAE)/ Changeable Flag0 or 1 / 0 (disabled

)

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Sub-System

Instance



EN_VAMOS_PAIRING_CA

When VAMOS is activated, enable/disable intracell HO for VAMOS pairing (cause 35) BSC Cell



EN_VAMOS_UNPAIRING_CA

When VAMOS is activated, enable/disable intracell HO for VAMOS unpairing (cause 34)

BSC Cell Site (CAE)/ Changeable Flag0 or 1 / 1 (enabled)

UL_VAMOS_PC_CORRECTION_FACTOR

Correction factor used to determine the transmitted powers of the paired MSs from the last computed DL RxLev value

BSC Cell Site (CAE)/ Changeable Number0 to 10 / 6 [dB]

SCPIR_NON_SAIC_VAMOS1_THR_1,...THR_2,...THR_3

Limits of the band N for distribution of SCPIR counters for (non-SAIC, VAMOS-1) pairs BSC Cell


-10 to +10 / 8, 10,10

[dB]

SCPIR_NON_SAIC_VAMOS2_THR_1,...THR_2,...THR_3

Limits of the band N for distribution of SCPIR counters for (non-SAIC, VAMOS-2) pairs BSC Cell


-10 to +10 / 8, 10,10

[dB]

SCPIR_SAIC_VAMOS1_THR_1...THR_2,...THR_3

Limits of the band N for distribution of SCPIR counters for (SAIC, VAMOS-1) pairs

BSC Cell Site (CAE)/ Changeable Threshold-10 to +10 /

-2, 0, 2 [dB]

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