radio networks capacity dimensioning guideline
TRANSCRIPT
•C2 – Vodafone Internal•Version 1.0•VTN
Radio NetworksCapacity Dimensioning Guideline
June 2010
• Rolf Fischer, Hans Jörg Hamers, Christoph Kenkel• VTN-Access-Design
•C2 – Vodafone Internal•Version 1.0•VTN
How to read this guideline / content
•2 •Radio Dimensioning Guideline, 2G, 3G •April 2010
This guideline covers a wide area of topics, sometimes very different.
To allow an easy read links ( ) to the several sections are used.From the beginning of any section it is easy to step back to this slide. Also coloured bars at the left are used to support easy orientation.
Introduction / Overview
High Level Dimensioning
2G dimensioning guideline
3G dimensioning guideline
2G/3G Network Utilisation
2G/3G traffic related interworking
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Introduction / Overview
•3 •Radio Dimensioning Guideline, 2G, 3G •April 2010
Intro
duct
ion
During the last years a 2G and a 3G capacity and dimensioning guideline were developed in close collaboration with the operators.
In order to allow a simple and fast read it was decided to choose Power Point format. Also 2G and 3G is put together into one guideline.
In any case the main goal of this guideline is to give support to the operating companies for the task of network dimensioning. It ensures that same way of planning is used and therefore the basement is build to deliver any possible benefit. Moreover, when OpCos using same principles and methods they can learn from each other in sense of best practise sharing.
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Introduction / Overview
•4 •Radio Dimensioning Guideline, 2G, 3G •April 2010
Intro
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High LevelDimensioning
The dimensioning follows a threefold approach with different level of detail to reach the goal of each step
Dimensioningwith planning tools
To support the high level dimensioning with more precise figures, but for shorter time frame, e.g. 1 year.
To do detailed network dimensioning with geographical references.
Based on complex tools, e.g. ATOLL
Dimensioning basedon counters andmeasurements
To get the quantitystructures for a given time frame, e.g. 3 years.
To support budget estimations.
Allows quick what-if analysis.
Based on ‘simple’tools, e.g. Excel or Access
To do the daily dimensioning work.
To assess when and which particular station has to be expanded.
To observe the network and the traffic evolution with geographical references.
This principle is valid for 2G and 3G as well as for LTE
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High Level Dimensioning
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1. High Level Dimensioning for 2G and 3G radio networks
a. The high level model
b. Alternative methodology 1
c. Alternative methodology 2
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Scope of High Level Dimensioning
• Estimation of required Radio equipment based on traffic figures to support any budgetary calculation
Support future planning, e.g. 3 year planTo perform what-if-analysis, e.g. what is required when subscriber do 10 times of data traffic compared to a reference
• The modelling covers normally radio only (carriers, base band and sites), but also radio access capacity (IuB) and RNC
• Input is:user traffic
absolute (# subscriber, min per sub per month, ….)relative, compared to a reference
network datanumber sites, carriers, ….
traffic translation parameter. e.g. billable to busy hour traffic (necessary to update from time to time)
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a. High Level Dimensioning, the High Level Model 1/4
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How the model works, overview1. Billable traffic is given per service (voice, CS64, R99 packet data, HSDPA and HSUPA)
-> translated into busy hour (BH) traffic, for each service individually -> divided into 16 different classes (per sector)
2. Network is given as totals, inclusive the planning for following years, expressed in #sites and #carrier (#TRX) -> divided into the same 16 classes
3. The traffic per class is compared with total capacity (in case of 3G sets as outcome from dynamic system simulations or measurements, in case of 2G a modified ErlangB table incl. HR, AMR-HR and GPRS)
For eachservice
MarketingForecast
For eachservice
BHNetworkTraffic
Network; Traffic & Mix
Network; Traffic & MixNetwork; Traffic & Mix
Current totalnetworkfigures
16 classes
Capacityfigures,Erlang B
Result:TotalDemand
Input required per OpCo
Parameter with hugeimpact on the results
Set 1Set 2
4. The result is the demand in terms of total carriers/TRX, total number node B/BTS, required base band boards, required IuB capacity, required number RNC. Each result is also available per class and could be further analysed.
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a. High Level Dimensioning, the High Level Model 2/4
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How the model works, detailed steps1. Cell Grouping (2G and 3G)
Basic concept is the grouping of cells or better sectors and traffic into 16 classes. This concept represents the inhomogeneous distribution of traffic in a mobile network. Each class describes sectors carrying a comparable level of traffic.An Excel sheet exists which allow the operator the classification: Sector-Classification Only traffic data needs to be filled in - same unit per service is mandatory - the analysis is done by the Excel sheet when pushing the calculation buttons.
2. Traffic Calculation (2G and 3G)Cell traffic per service and busy hour is calculated, expressed in number average and 95% percentile users per service. Input are the numbers subscribers, monthly usage per service and several translation factors.
3. Scenario Assignment (3G only)According to the calculated busy hour traffic figures a scenario is chosen which fits best to given traffic mix. The decision based on a smooth interpolation. The scenario considers voice, video telephony, R99 non-real-time and real time services and HSPA.
4. Utilisation calculation (2G and 3G)Based on a modified Erlang B table and 3G cell capacity settings the utilisation per resource is calculated for each cell of a class.
5. Expansion calculation (2G and 3G)According to the utilisation result required expansions are calculated in terms of 2G TRX and 3G carrier. When further TRX or carrier (individual operator setting and license conditions) could not be installed at the cell capacity nodeB or BTS are calculated.
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a. High Level Dimensioning, the High Level Model 3/4
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How the model works, detailed steps6. CE calculation
Based on the 95% percentile of active subscribers per service and busy hour the required base band capacity is calculated and compared with the CE settings per vendor. Based on this a recommendation is made which cell class needs which board out of a set of standard configurations.
7. IuB bandwidth calculationThe IuB bandwidth calculation is also possible. Basis is again the 95% percentile of active transmitting subscriber per cell. Lot of parameters can be set, whereas the reserved bandwidth for HSDPA traffic is important.
8. RNC calculationThe final step is the requirement of needed RNC. Per vendor standard RNC configurations can be defined which build the basis for this calculation.
9. Additional statisticsBeside the mentioned results some more statistics are available which allows more analysis and to check the intermediate calculation steps, for instance the cell traffic per busy hour or the users per cell and busy hour.
More information about the model can be found in the back up and in the best practise sharing teamroom <LINK>
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a. High Level Dimensioning, the High Level Model 4/4
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c. Alternative 1 High Level Model methodology 1/3
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When lot of network measurements on cell level are available an alternative (to the RDC High Level Model) methodology could be used
• for mature networks with slow coverage roll out valid• for strong growing networks at least valid for the old network part
1. The method is to use relative growth figures of marketing forecasts2. Adapt this growth to the busy traffic measurements of each cell3. Compare the resulting traffic with capacity tables (3G) or Erlang B
model (2G)
ADVANTAGE• Can be much more accurate, because the network is not classified in
16 classes only, each cell/sector/site could be considered individually• Cell specific restrictions can be considered, e.g. different limitations
in the spectrum (border regions, different interference situations)• Possibility to apply different traffic growth to cell individually when
some history is available
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c. Alternative 1 High Level Model methodology 2/3
•11 •Radio Dimensioning Guideline, 2G, 3G •April 2010
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Year 04/05 05/06 06/07 07/08 08/09 09/10 10/11 11/122G voice 39014 40581 45000 46000 45000 40000 35000 300003G voice 0 2871 4500 6965 11673 20640 30000 40000
Ratio UMTS BH-voice 0% 64% 100% 155% 259% 459% 667% 889%1 2 3 4 5 6 7
2G Data 10 20 32 42 54 70 75 803G Data 0 50 110 143 186 242 255 270
Assumption HS/R99 split 0% 0% 50% 57% 63% 70% 75% 80%R99 Data 0% 0% 100% 148% 213% 308% 348% 393%
HSDPA Data 0% 91% 100% 112% 125% 132% 116% 98%
Max of DLP 06/07 07/08 08/09 09/10 10/11 11/12CELL-ID AVG2 AVG2 AVG2 AVG2 AVG2 AVG2
62 27923.5 43219.37 72430.77 128073.5 186156.67 248208.9751 101380.5 156914.5 262970.9 464990.2 675870 901160752 88037 136261.7 228359.2 403789.1 586913.33 782551.1753 101525 157138.1 263345.7 465653 676833.33 902444.4761 22645 35049.43 58738.87 103863.2 150966.67 201288.9762 24550.5 37998.72 63681.54 112602.9 163670 218226.7763 18858.5 29188.77 48917.06 86496.1 125723.33 167631.1791 23615.5 36551.55 61256.25 108314.5 157436.67 209915.6792 54107.5 83746.39 140349.4 248168.6 360716.67 480955.6793 14496 22436.59 37601.17 66487.12 96640 128853.3801 121323 187781 314699.7 556458.1 808820 1078427802 53966.5 83528.15 139983.7 247521.9 359776.67 479702.2803 316394.5 489708.4 820695.7 1451170 2109296.7 2812396822 11375 17605.97 29505.61 52172.39 75833.333 101111.1901 57783.5 89436.02 149884.6 265028.9 385223.33 513631.1902 59342 91848.23 153927.2 272177.1 395613.33 527484.4903 18325 28363.03 47533.22 84049.15 122166.67 162888.9931 22289.5 34499.19 57816.73 102232.7 148596.67 198128.9932 26219 40581.19 68009.46 120255.6 174793.33 233057.8933 59526 92133.02 154404.5 273021 396840 529120
FORECAST
Example
Input: Busy Hour traffic forecast
Reference Year
Input: Cell leveltraffic measurementsduring busy hour
Adaptationof relativetrafficgrowth toeach cell
relative growthper service ortechnology
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c. Alternative 1 High Level Model methodology 3/3
•12 •Radio Dimensioning Guideline, 2G, 3G •April 2010
Used for 06/07 to 07/08 Used for 08/09 onwardsCapacity settings, original for 5 Codes HSDPA and cat. 6 Capacity settings, new for 10 Codes HSDPA and cat. 8
Voice VT R99 HSDPA Voice VT R99 HSDPAUser 12.9 0.7 2.6 0.7 User 12.0 0.6 2.4 0.7min/MB 773 42.4 35.5 56.8 min/MB 717.6 39.4 33.0 113.6kbits 565836 162816 290816 465306 1484774 kbits 525257 151140 269960 930611UL-util/use 5.60% 24.70% 3.80% 1.40% 100% UL-util/use 5.97% 26.32% 4.05% 2.98%DL-util/use 4.40% 29.50% 5.60% 11% 100% DL-util/use 4.40% 29.50% 5.60% 20%Code-util/u 1.10% 4.42% 6.15% 0% 66% Code-util/u 2.20% 8.84% 12.30% 0%
852 06/07 07/08 08/09 09/10 10/11 11/12 06/07 07/08 08/09 09/10 10/11 11/12Carriers Allowed Cell Identifier 0 2 24 32 39 54 AVG2 AVG2 AVG2 AVG2 AVG2 AVG2
2 62 0.34 0.35 0.38 0.41 0.43 0.46 27923.5 43219.37 72430.77 128073.5 186156.7 248208.92 751 0.43 0.45 0.64 0.75 0.99 1.29 101380.5 156914.5 262970.9 464990.2 675870 9011602 752 0.55 0.59 0.95 1.06 1.09 1.25 88037 136261.7 228359.2 403789.1 586913.3 782551.12 753 0.40 0.41 0.56 0.69 0.98 1.29 101525 157138.1 263345.7 465653 676833.3 902444.42 761 0.37 0.37 0.44 0.46 0.48 0.49 22645 35049.43 58738.87 103863.2 150966.7 201288.92 762 0.38 0.39 0.47 0.51 0.52 0.53 24550.5 37998.72 63681.54 112602.9 163670 218226.72 763 0.38 0.39 0.47 0.49 0.50 0.50 18858.5 29188.77 48917.06 86496.1 125723.3 167631.12 791 0.41 0.42 0.55 0.59 0.59 0.59 23615.5 36551.55 61256.25 108314.5 157436.7 209915.62 792 0.50 0.53 0.80 0.88 0.88 0.89 54107.5 83746.39 140349.4 248168.6 360716.7 480955.62 793 0.33 0.34 0.35 0.36 0.38 0.39 14496 22436.59 37601.17 66487.12 96640 128853.32 801 0.40 0.42 0.58 0.79 1.13 1.50 121323 187781 314699.7 556458.1 808820 10784272 802 0.48 0.50 0.73 0.80 0.82 0.83 53966.5 83528.15 139983.7 247521.9 359776.7 479702.22 803 0.52 0.71 1.22 2.09 2.97 3.92 316394.5 489708.4 820695.7 1451170 2109297 28123961 822 0.39 0.40 0.48 0.50 0.50 0.49 11375 17605.97 29505.61 52172.39 75833.33 101111.11 901 0.52 0.55 0.86 0.94 0.94 0.94 57783.5 89436.02 149884.6 265028.9 385223.3 513631.11 902 0.39 0.40 0.52 0.58 0.63 0.75 59342 91848.23 153927.2 272177.1 395613.3 527484.41 903 0.71 0.75 1.28 1.35 1.25 1.14 18325 28363.03 47533.22 84049.15 122166.7 162888.9
Max - Utilisation, either UL, DL or Code
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Example
trafficestimation
Technology dependent lookup tables
results in termsof utilisation
Consideration ofcell individualproperties
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d. Alternative 2 High Level Model methodology 1/3
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This alternative is based on real network experience, on networkcounter and data ware house analysis
0
2.000
4.000
6.0001.484
105
330 - 5 5 - 10 10 - 15 15 - 20 20 - 25 25 - 30 30 - 35 50 - 55
0
500
1.000
1.500
Datenvolumen Luftschnittstelle in GByte KW42 / 2007
Anz
ahl N
odeB
Anzahl B
lockierungen pro NodeB
NodeBPmnoreqdeniedadm
Data volume per nodeB per week
Num
ber n
ode
B
Total blockings per week
Analysis show that from a volumeof about 25 Gbyte the blockings getssignificant
Cross check: A “good” site with up to 20 GByte per week shows that a extratest unit still gets more than 1 Mbps inaverage (3,6 max), also during busy hour!Total average cell throughput: 2 Mbps
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d. Alternative 2 High Level Model methodology 2/3
•14 •Radio Dimensioning Guideline, 2G, 3G •April 2010
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Further analysis of data ware house data (billing system) of the “good”site shows:
Number user with more than 1 MByte (per month, looking only at users making significant traffic) WWW traffic:
in the busy hour (BH): 24per day: 48per week: 87per month: 137
Service/traffic behaviour per user (> 1MByte/month WWW traffic) :Average volume per user in BH: 12 MBAverage session duration: 45 min=> Activity per session @ 1 Mbps: ~3.5%
Total duration of those users: 48 hourstypical BH activity: 10%=> Probability of user being active during busy hour: ~0.6%
=> 2 Mbps / 0.6% ~ 300: 300 of those WWW users can be served in the area of ONE cell, each of them perceives 1 Mbps throughput during BH
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d. Alternative 2 High Level Model methodology 3/3
•15 •Radio Dimensioning Guideline, 2G, 3G •April 2010
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ADVANTAGE• Very simple approach, allowing simple site/node B dimensioning
when number of customer in a service area is available and predictable, e.g. at home products
DRAWBACK• Final capacity per site/nodeB
- depends on traffic mix (voice and data services)- depends strongly on how services are used by the customers- depends strongly on when services are used by the customers (daily traffic profile)
• Difficult to find a representative cell in a network or part of a network
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2G Dimensioning Guideline2G features included in the High Level Model and also applicable for the counter based dimensioning
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1. Half Rate• Concept is that a single connection (either FR or HR) occupies one effective
TCH
– TCH physical number of traffic channels in a cell – HR% ratio between HR calls to the total calls (HR + FR)
• Example: Cell with two trx and fully utilized:
– number of TCHs = 14– Effective TCHs = 17 (11 FR connections and 6 HR connections)– 35,5% half rate ratio
• The modified Erlang-B formula is
%22%),(
HRTCHHRTCHCHEffectiveT
−×
=
FR FR FR FR FRHRHR
HRHR
BCCH FR FR FR FRSDCCH HRHR FR
FR
),(%),,( CHEffectiveTGoSfficCarriedTraErlangBHRTCHGoSfficCarriedTra =
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2. Queuing 1/2• VF RO developed and extended Erlang B formula where
Offered Traffic = f (GOS, No_Channels, Queue_Length, Mean_Holding_Time)– Queue Length = 0 Extended Erlang B = Erlang B– Queue Length = infinite Extended Erlang B = Erlang C
• Capacity increase: +15% compared to Erlang B– HR (traditional or AMR) can still be deployed on top for further efficiencies
Theoretical Grade of Service (%) vs. Traffic offered (Erlangs) - 2 Transceiver, 13 traffic channels scenario
0.00
5.00
10.00
15.00
20.00
25.00
30.00
35.00
40.00
4 5 6 7 8 9 10 11 12 13
Traffic offered (Erlangs)
Gra
de o
f Ser
vice
(%)
GoS - VR RO's modified Erlang B GoS - Classical Erlang B
Erlang B, 2% GoS
Extra capacity
Extended Erlang B, 2% GoS
2G Dimensioning Guideline2G features included in the High Level Model and also applicable for the counter based dimensioning
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2. Queuing 2/2• The formula for the loss (abandon) probability is:
– E(N,A) = Erlang B blocking probability– A = offered traffic– N = number of channels– d = queue waiting time * service rate; service rate = 1/ mean holding time
e.g. maximum queuing time 7.5 secmean holding time 29 sec
• VF-Romania and Vodacom South-Africa have already introduce Queuing into their 2G network. The statements we got are positive concerning– complaints from their customers– network performance counters
P l = APN * [A – N+
CN ]
NP = EC
ANEC*)1(1
),(*−+
C = 1 + AN
eA ANd
−− −− )1( )(
where
and
2G Dimensioning Guideline2G features included in the High Level Model and also applicable for the counter based dimensioning
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3. Data traffic (GPRS/EDGE) forecast 1/3• Some useful definitions:
– PDCH utilisation is the filling factor for the allocated (active) PDCHs– Radio Link Bandwidth is the bandwidth one user would get if he was the only
active user in the cell– End-user throughput is the throughput an end user experiences when using
TCP/IP based applications:
• Example:– One TRX cell with combined BCCH/SDCCH– MMS users primarily using 4-slot mobiles– 10 kbps average radio-link bit rate per PDCH– MMS of size 30 kByte shall take no longer than 8 seconds– 2.2 Erlang traffic in the cell– Average number of PDCHs carrying data 2.4
• Workflow:1. Radio-link bandwidth = 4x10 kbps = 40 kbps2. Required throughput: 30kByte/8 seconds = 30 kbps
2G Dimensioning Guideline2G features included in the High Level Model and also applicable for the counter based dimensioning
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3. Data traffic (GPRS/EDGE) forecast 2/3• Workflow (continue):
3. Using simulation results shown in the graph on the right, follow the curve corresponding to Radio Link Bandwidth of 40 kbps. Using this curve the requirement of 30 kbps translates into a PDCH Utilisation of no more than 0.4 (40%)
4. Thus we get the minimum required number of PDCHs in the cell = 2.4/0.4 PDCHs = 6 PDCHs (in the present configuration an average of 4.8 PDCHs are available)
5. There are three options to get the required average 6 PDCHs in the cell:
• Offload the cell from voice traffic to get 1 Erlang traffic or lower.
• Dedicate 6 FPDCHs in the cell (not a realistic option)
• Expand the cell with a second TRX
Simulation results
2G Dimensioning Guideline2G features included in the High Level Model and also applicable for the counter based dimensioning
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e 3. Data traffic (GPRS/EDGE) forecast 3/3• Workflow (continue):
6. If no action is taken, a median end-user throughput of 27 kbps can be reached (download time 8.9 seconds)
Some additional information about data traffic settings• PILTIMER: Common setting is 5 seconds. Lowering the timer increases
resource efficiency. On the other hand, too low PILTIMER increases average PDP allocation time. The time difference in PDP allocation time on a cell with expired and non-expired PILTIMER is about 200 ms.
• 'fixed' vs 'on demand' PDCH: An additional delay of about 200 ms is experienced during call setup in a cell only deployed with 'on demand' PDCH compared to a scenario where a cell already has at least 1 PDCH allocated.
2G Dimensioning Guideline2G features included in the High Level Model and also applicable for the counter based dimensioning
2G Network Utilisation• This will be discussed together with the 3G Network Utilisation (please follow
this link:
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Example of GPRS Standard Configuration
• GPRS implemented only on BCCH trx;
• Dedicated tsl >=2 (2 for cells with lower capacity i.e. 2trx);
• Dedicated + Default tsl <=6.
2G Dimensioning Guideline2G features included in the High Level Model and also applicable for the counter based dimensioning
CircuitSwitchedTerritory
PacketSwitchedTerritory
CCCH
TS TS TS TS TS TS TS
BCCH
TS
TS TS TS TS TS TS
TRX2
TRX1
DedicatedGPRS
Capacity
Territory border movesdynamically based on
Circuit Switched traffic loadi.e. voice downgrades data traffic
Frame
DefaultGPRS
Capacity
AdditionalGPRS
Capacity
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3G Dimensioning Guideline
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eContent of the 3G dimensioning guideline
Dimensioning for 3G radio networks
a. Step1: High level dimensioning (see section before )
b. Step2: Capacity planning with planning tools(not practiced within Vodafone -> high level way of proceeding see next section)
c. Step3: Capacity planning based on counter
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3G Dimensioning Guideline
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eStep 2: Capacity planning based on planning tools
Objective
• The planning of capacity based on planning tools is the next logical step after high level dimensioning
• This step takes among other things a geographic traffic map into account and allows therefore a detailed planning which site has to be expanded or in which area capacity sites needs to be build
• Planning tools perform the capacity planning by means of Monte Carlo simulations
Prerequisites
• As geographic traffic maps are used for the capacity planning it is crucial to use a traffic map with high quality1. Based on cell level measurements of 2G networks when 3G
networks are newly introduced or 3G traffic is very low2. Based on cell level measurements of 3G networks3. A appropriate tool to compile traffic maps based on cell level
measurements is available as a special add on module for ArcGis
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3G Dimensioning Guideline
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Dimensioning steps 1/3
The dimensioning with planning tools is an iterative process, which needs to be repeated as long as several KPIs are not fulfilled
1. The first step is to do a coverage analysis part 1 (e.g. coverage by signal-level). For this step the correct definition of sites, transmitters and cells is required as well as suited geographic elevation and land use data together with a proper propagation model.For this step no traffic map is required, the coverage map is based on pilot reception level only (RSCP).
2. The second step starts the capacity planning by performing a number of Monte Carlo simulations. Main output is the load of importantresources (DL power consumption, uplink interference level, code tree utilization)- Each simulation step contains at least 20 simulations- The traffic map needs to be scaled correctly for the point in time
the planning is done (normally end of next fiscal year)
Step 2: Capacity planning based on planning tools
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3G Dimensioning Guideline
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Dimensioning steps 2/3
3. The third step is the capacity analysis by analysing the results of the Monte Carlo simulations.- The basic result statistics gives an overview on network
performance in terms of users rejected and rejection reasons.- Average results of important parameters are available for each cell,
indicating problem cells4. In parallel to the third step the coverage analysis part 2 should be
done. This step takes the load results of step 2 into account. The analysis should be done for the pilot (Ec/Io) and for the reference service (effective service area). Any coverage holes under load conditions can now be detected.
5. If the results of step 3 and 4 doesn’t meet the requirements a (planning) optimisation of the transmitters, cells and antennas should be done.
After optimisation steps 1 to 4 needs to be repeated (iterative process!)
Step 2: Capacity planning based on planning tools
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Dimensioning steps 3/3
6. If optimisation of the given network is not sufficient enough to cope with the (forecasted) traffic demand, network extensions needs to be planned- Introducing of 2nd carrier on highly loaded sites- Filling coverage holes with new sites- Introducing capacity sites in order to unload a number of overloaded
sites of a cluster
Step 2: Capacity planning based on planning tools
In general the steps 1 to 6 needs to be repeated several times until the required targets are meet.
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Objective
• This step describes the dimensioning of individual sites during the daily work (mostly performed in regional offices). This is done by observation of important network counters of individual sites. In contrast to step 2 it is not based on planning data and model assumptions, it is based on the network and real life conditions.
Content
1. Expansion triggers
2. Expansion options
3. Examples
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In general a pair of threshold for each important KPI needs to be defined
1.First threshold, indicating that a cell or site switches from low load to a mid to high load situation, so to say from green to yellow status
=> a planning action needs to be triggered, with enough time inadvance before any action can be done and threshold 2 is meet
2.Second threshold, indicating that a cell or site switches from a mid to highload situation to a overload situation, so to say from yellow to red status
=> a action needs to be taken immediately to solve the overload situation,a proper planning is pre-condition
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The lead time t is individual for each KPI to be measured and therefore the setting of T1 and T2. For example the extension of a site with additional base band capacity is much faster done than the introduction of a fill in capacity site.
T 2T 1
t time
Several open points exists:
1. The system can be further refined, for instance with a hysteresis on the time axis.This might avoid expansions do to seasonal effects as indicated with the dotted line.
2. Or depending on a site classification different thresholds T1 and T2 can be applied, for instance to distinguish basic and premium level coverage areas. Areas with lower importance may have a more relaxed threshold T1 (or T1 and T2)
As aggregation method for any KPI as busy hour (BH) the MAVG8 method takes place (8 highest peaks on separate days of a month). This is the same definition as used for the utilisation reporting.
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Parameter/Trigger Basic coverage(HSPA, up to 14.4 DL peak)
Hot spot coverage(HSPA+, up to 43.2 DL peak)
GoS (for CS services, independent from the blocking reason)
2% 2% User
PerceptionAverage user throughput
(HSDPA/HSUPA)2500 kbps / 1000 kbps 4000 kbps / 2000 kbps
DL power for R99 traffic (incl. common channels)
67.5% of max PA power 67.5% of max PA power
Resource U
tilisation
Code tree utilisation (incl. R99 and HSDPA)
67.5% 67.5%
UL Load (R99 only)UL Load (R99 + HSUPA)
60% (4 dB noise rise)75% (6 dB noise rise)
60% (4 dB noise rise)75% (6 dB noise rise)
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Aligned to the HSDPA guideline following triggers are defined, during the BH, depending on a general definition of coverage areas, differentiated between1. triggers based on user perception2. triggers based on resource utilisation
Step 3: Expansion triggers and thresholds 3/3
The values shows only the triggerfrom yellow to red status!The thresholds for green to yellowstill to be defined.
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eWhen one of the triggers listed on the page before is exceeded actions has to take place to solve the overload situation. Following options exists:
Step 3: Expansion options
1. Optimisation (when not happened so far) • changing the antenna direction (tilt or azimuth)• power settings (e.g. different pilot)• handover settings to all surrounding or specific neighbour cells=> helps mainly in case of downlink or uplink interference problems
2. Base band expansion=> only when base band capacity is limited
3. Carrier expansion (when cluster cannot be further optimised)• dividing R99 and HSPA traffic on separate carrier• equal distribution of traffic on both carriers• adding an amplifier with higher power (when not happened so far)=> suited for interference problems and code tree limitations
4. Cell splitting• Introducing higher order sectorisation• Introducing capacity fill in sites• Customized solutions (indoor, e.g. when lot of traffic comes from a business
customer, or VAP etc.)=> helps in case of all limitations
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•2nd and 3rd Carrier Deployment 1/3
General RequirementsThe 2nd carrier deployment basic rule:
For HSPA 28.8 and 21.6 coverage area: 2 carrier mandatory
For HSPA 3.6, 7.2 and 14.4: demand driven, 1 carrier default
HSUPA 1.4 or 2 does not trigger an 2nd carrier by default,upgrade threshold driven (see next slides)
Dynamic clustering for 2nd carrier is recommended (no fixed rings, fixed factors, etc.)
– Tool based planning with ATOLL in dependence of predicted traffic– “Cluster” of only one node B possible if traffic distribution indicates this– Cluster size is demand driven no special requirements to cluster geometry
The general parameterization of each carrier should be as follows
– The traffic should be diverted between the carriers in order to deliver the best performance for HSDPA users
– In case that R99 cannot be carried on the first carrier an overflow onto the second carrier should be allowed
Before adding another carrier to a cell/sector it has to be ensured that optimization of antennas and radio resource management parameter is already on best level to maintain as low as possible interference
Tool based andcounter basedequivalent
•Demand driven carrier upgrade,•2nd carrier in HSPA+ areas as a default
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Principal design, which may differ in details depending on vendor releasesIt is beneficial to separate as much as possible circuit (R99) and packet (HSPA) switches traffic
The upgrade is strongly traffic demand driven, i.e. HSPA upgrade on 1st carrier possible*
It is assumed that majority of packed switched traffic is carried with HSPA technology
•2nd and 3rd Carrier Deployment 2/3
•default:3G carrier is used for both,HS and PS traffic.
•loaded sites:• 1st 3G carrier is mainly used
for R99 traffic• 2nd 3G carrier is mainly used
for HS traffic
•high loaded sites:• 1st 3G carrier is mainly used
for R99 traffic• 2nd 3G carrier is used for R99
and HS traffic• 3rd 3G carrier is used for HS
traffic
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Expansion rulesDefault up to 14.4 Mbps coverage areas is the1 carrier solution
2nd or 3rd carrier upgrade triggered bytotal traffic (sum of R99 and HSDPA) respectively resource shortage2nd or 3rd carrier upgrades are considered whenone of following criteria is meet during thebusy hour1:- 2% of blocking (for CS services) is reached - DL power utilization is above 67.5% with to
total available amplifier power- Code tree utilization is above 67.5%
(total codes for R99 and HSDPA)- user throughput falls below 500 kbps by
means of counter measurementsOnce UL counters deliver secure results- UL2 interference is above 4 dB (~60% load)
for R99 in UL only- UL2 interference is above 6 dB (~75% load)
when HSUPA is available
1 1 The busy hour is defined as the average of the 8 busiest hours of a month. Each individual busy hour is defined by the highest used resource, which could be UL interference, DL power utilisation or code tree utilisation.
2 2 The UL counters delivers currently still unsecure results. Therefore it is possible to exclude UL as expansion trigger
•2nd and 3rd Carrier Deployment 3/3
•75%•67,5%•Power usage [%]
Busy hour measurements:Resource utilisation is measured as mean value during the busy hour. It is of course possible that the peaks within these periods go up to 100%, which is necessary to reach peaks of 14.4 Mbps
Real network
example for power
utilisation
Additional upgrade conditions:•In any case before introducing next carrier it must be checked that the bottle neck is within the air interface (exclude base band, IuB and Core)•If it is turned out that only 1 or 2 high power users are responsible for high resource utilisation, upgrades shouldn’t be done
Upgradethreshold
10% Margin to allowtime for evaluationand planning
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Similar to the HSDPA guideline 3 KPI are observed to detect the need for a second carrier expansion1. DL Channelization Codes2. DL Power3. Optional: HSDPA throughput1
Basic rule• A cell should be considered as a candidate for 2nd carrier expansion when the RAB establishment
failure ratio reaches 2% (for CS services) in the monitoring period• 50% of the RAB failures due to lack of DL power• 50% of the RAB failures due to lack of DL channelization codes• 70% of the RAB failures due to the sum of both reasons above• Average user throughput falls below 700 kbps respectively 1200 kbps for 10% of time1
Monitoring period• In line with the current busy hour definition a cell should be considered for 2nd carrier expansion
when the conditions of the basic rule applies 8 times per month at different days.
Is the cell finally optimised?• Before adding a 2nd carrier it is mandatory to check that a cell cannot be further optimised
– in terms of changing antenna parameter for interference minimisation– in terms of changing admission control parameters (e.g. reducing allowed SF8 RAB)– in terms of changing handover settings and relations …..
1 The HSDPA throughput criterion is optional, because- it can happen that applications does not require a high throughput- that somewhere else in the network a bottleneck exists, e.g. access transmission
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2G/3G Network UtilisationMotivation
1. Gives transparency on the capacity pressure on each network
2. Fair comparison with a unique and aligned method
3. Is increasingly requested by higher management level, e.g. for Investor Relations report
Why is network utilisation reporting so important?
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2G/3G Network UtilisationWhat does utilisation mean/express
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2G/3G Network UtilisationWhat does utilisation mean/express
Access network utilisation measures the physical resource usage …
DL Power
UL Noise
Codes
Channel Elements
75% load (design target) = 100% ‘utilisation’
3G Resource loading
Overall utilisation = MAX
resource
TRX
Capacity acc. ErlangB according to the design target = 100% ‘utilisation’
2G Resource loading
Overall utilisation = TRX
utilisation
… but in 3G it is not as easy as it is in 2G!
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Beside average utilisation a subset of KPIs have been defined to allow better understanding of situation, e.g.:Load distribution, resource & traffic are needed & KPIs have been defined
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2G/3G Network UtilisationWhat does utilisation mean/express
Tech Resource Impact to customers during congestion
Correlation: Resource load to traffic
Solution
2G TRX (transmission and reception unit)
Increased blockingReduced GPRS throughput
Very strong More TRX
3G DL power, UL Noise, Codes
Lower user throughput, lack of coverage, increased service blocking
Weak Additional CarrierHigh power PA
3G Base Band Units Lower user throughput, increased service blocking
Middle More base band boards
2.000€
5.000€
1.200€
By considering the individual impacts of the resources it is possible to perform an assessment in terms of customer & financial impact
As consequence the base band utilisation is excluded from 3G KPI120 and will be reported as separate KPI (KPI119) in futureDue to ongoing technical problems with UL measurements and weak correlation to traffic, UL utilisation is not longer included in the MAX function of KPI120,but still reported as sub KPI 120d
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2G/3G Network UtilisationIntroduction of Targets
Situation todayUtilisation KPIs are well defined for a certain period, allowing relative comparison in time and between networks
Absolute targets/thresholds are defined yet, but implementation are not fully completed
What should a target fulfil?Indicate a healthy range of utilisation!Only few sites are allowed to be in overload situation where our customer suffer from bad qualityOnly few sites low loaded, telling about inefficient use of resources
The average network utilisation does not tell very much about over- or under-loaded sites, therefore it is better to look at the tail ends
0
0.005
0.01
0.015
0.02
0.025
0 20 40 60 80 100 120
The focus will be on the high loaded sites
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2G/3G Network UtilisationTargets, 2G
Most critical cells are locatedin the light-blue area, candidatesfor expansion:• high utilisation (>100%)• high HR (>40%)
18%
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2G/3G Network UtilisationTargets, 3G
Main quality measure in 3G would be HSDPA user throughput
Targets:
#cells < 5%
#cells < 10%
#cells >= 10%
Most critical cells, candidatesfor expansion:
high utilisation (>90%)
~ 2%
~ 1%
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2G/3G Network Utilisation3G Radio Network Utilisation, QMIS KPI 120 family
The KPI family contains of one main KPI and additional supporting KPIs giving more background information to improve understanding.3G networks have several resources which needs to be considered:- Power in the DL available for each cell- The codes available for each cell- The UL interference allowed in each cell- The base band capacity boards to process the calls in each node BThe final result for KPI 120 is the maximum of the utilisation of each resource. But different resources implies different actionsCapacity assumed is always valid for one common design target per resource, which is typically 75% of total available resource. This is necessary to cope with fluctuations in the traffic during busy hour.Each KPI is calculated as average of 8 busiest hours of a month occurring at 8 different days. The busy hour is defined cell individually as highest utilisation of the resources.A second busy hour definition exists based on traffic (MByte) carried in a cell. This busy hour is typically different from the busy defined on the resources.
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2G/3G Network Utilisation3G Radio Network Utilisation, QMIS KPI 120 family
Mean 3G Radio Network Utilisation.Results can be high because the highest value of the 4 considered resources is reported. To draw conclusions analysis of sub KPIs are recommended.
Main KPI 120
Percentage of the network with a utilization above 90%, indicates critical cell which needs extension when traffic further increase.
PI 120 a
Average DL power utilisation. To resolve this additional carrier required, but high values are less critical in case that HSDPA traffic is the driver.
PI 120 c
PI 120 b Percentage of the network with a utilization below 10%, indicates parts of network with very low traffic, mainly cells intended for coverage only.
Average UL interference utilisation. Higher values than the design target decreases the coverage mainly. To resolve additional carrier required.
PI 120 d
Average Code Tree utilisation. To resolve this additional carrier required.
PI 120 e
Important: Compared to 2G networks 3G is a new technology. Capacity is soft and theoptimisation of network design and radio resource management can improve utilisation,this means carrying more traffic with less utilised resources.
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2G/3G Network Utilisation3G Radio Network Utilisation, QMIS KPI 120 family
Total BH traffic (throughput) per cell during busy hour defined when radio resource a maximal utilised.
PI 120 h
As KPI 120, but the utilisation is measured during hours when traffic is maximal instead when resources are maximal utilised.
KPI 120 i
As KPI 120 h, total BH traffic (throughput) per cell, but busy hour is defined when traffic is maximal.
PI 120 k
Busy hour traffic of several services: voice, video telephony, R99 data, HSDPA and HSUPA data
PI 120 l - p
Percentage of soft handover traffic, needed to assess KPI 120 l-p depending of counter capabilities per vendor.
PI 120 q
It is important to point out that in contrast to 2G in 3G two different busy hours exists.Firstly the busy hour of the resources which drives the required network extensions when no further optimisation is possible, secondly the busy hour of resources, when most traffic is carried. It is typical that both hours are not the same, because high usage of HSDPA as more efficient technology reduces utilisation compared to cases when voice or R99 data are highly used.
Link to the whole document: <LINK>
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2G/3G Network Utilisation3G Radio Network Utilisation, Base Band
Mean Base Band Utilisation.It is the maximum of DL and UL base band utilisation. To draw conclusions analysis of sub KPIs are recommended.
Main KPI 119
Percentage of the network with a utilization above 90%, indicates critical node B which needs extension when traffic further increase.
PI 119 a
PI 119 b Percentage of the network with a utilization below 10%, indicates parts of network with very low traffic, mainly node B intended for coverage only.
Important: There is no further differentiation between UL and DL, because the mapping is very different from vendor to vendor. Some of them have a common resource for both directions.
Link to the whole document: <LINK>
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2G/3G Network Utilisation2G Radio Network Utilisation, QMIS KPI 110 family
The KPI family contains of one main KPI and additional supporting KPIs giving more background information to improve understanding.2G networks have one resource which needs to be considered:This is the number of time slots per cell.Capacity assumed is always calculated for one common design target, which is 40% usage of half rate and for 2% blocking ratio, independent from OpCo individual targets. This allow a fair comparison.Each KPI is calculated as average of 8 busiest hours of a month occurring at 8 different days. The busy hour is defined cell individually as highest number of used time slots.
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2G/3G Network Utilisation2G Radio Network Utilisation, QMIS KPI 110 family
Mean 2G Radio Network Utilisation.Values higher than 100% are possible, when- HR usage during busy hour is much higher than 40%.- 2% of blocking cannot be maintained during busy hour.
Main KPI 110
Percentage of the network with a Utilisation above 90%, indicates critical cell which needs extension when traffic further increase.
PI 110 a
Percentage of GPRS/ EDGE traffic.PI 110 c
PI 110 b Percentage of the network with a utilization below 10%, indicates parts of network with very low traffic, mainly cells intended for coverage only.
HR ratio design target, helps to justify the main result.PI 110 d
Blocking design target, helps to justify the main result.PI 110 e
AMR half rate terminal penetration. Independent if AMR-HR feature is activated or not. This KPI should show the potential which AMR-HR could have. Not necessarily to be updated every month.
PI 110 f
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2G/3G Network Utilisation2G Radio Network Utilisation, QMIS KPI 110 family
Total HR (conventional HR + AMR HR) percentage of total traffic (FR + HR) during busy hour.
PI 110 h
Percentage of cells which fulfil two conditions: Total HR > 40% AND Utilisation > 100% (combined trigger). Please note the total HR traffic consists of the sum of AMR HR and conventional HR.
PI 110 i
AMR-HR percentage of total traffic once the feature is introduced. High values allows good speech quality although HR is used and only half of capacity per customer is required.
PI 110 g
Link to the whole document: <LINK>
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2G/3G Network UtilisationChallenges
2GDuring redefinition in 2007 it was agreed to use constantly 20% of HR for each OpCo to allow fair benchmarking. But this does not reflect reality, leading to very high utilisation (>95%) although voice quality is ok.=> Redefinition to 40% in 2009 during introduction of targets
3GUL utilisation (120d) causes many problems due to foreign interference (e.g. DECT phones) and unreliable measurements=> introduction of more sophisticated method – without success=> finally excluded from KPI120 to avoid hiding results of more important
DL or Code utilisationIn many cases base band utilisation has driven final result of KPI120=> Separated as separate KPI (119) to avoid hiding air interface utilisation
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2G/3G Traffic related interworkingIntroduction
•April 2010•Radio Dimensioning Guideline, 2G, 3G•52
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tThe recommendations regarding traffic management between 2G and 3G has the central goal to use the overall resources in the most efficient way
• from a customer perspective in terms of highest quality of service• from the economical point of view in terms of lowest costs
Traffic management is also driven by the general strategy, for instance
• When an operator has the strong interest to get rid of 2G as fast as possible the interest is to push as much as possible traffic on 3G=> This may require more investments in 3G needs to be done earlier
• Is the strategy to use both radio networks in parallel with less than possible radio equipment the strategy can be, to push voice onto 2G and to push packet data services onto 3G=> Probably higher OPEX costs due to longer time for running 2 networks in parallel
Calculations by means of high level calculations for traffic management is one piece of a puzzle for delivering input for strategic decisions, but not the main driver. Therefore a strategy per OpCo is seen as predetermined.
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2G/3G Traffic related interworkingIRAT Parameterisation – Motivation and Basic Idea
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Goal: keep as much traffic as possible in 3G and avoid non-necessary 2G capacity investments
• Relax voice IRAT thresholds to delay 3G to 2G HO and keep 3G voice traffic in 3Gnetworks
• To switch cell change order off for packet• Have a very relaxed PS IRAT threshold (alternative: switch triggers off)• Expectation: HS to R99 transition due to coverage reason is avoided / minimised
Remark:• 2G/3G handover is still problematic for some vendors• => Focus to 3G/2G handover trigger in this guidelines
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2G/3G Traffic related interworkingIRAT Parameterisation – Goals and Recommendations
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tGoal: Efficient traffic handling in 2G/3G networks– Maximization of 3G Voice-Usage to avoid unnecessary 2G investment
– Minimization of compressed mode activity
– Minimization number of 3G -> 2G HO
– Securing Voice quality and stability
Current status of 2G/3G HO procedures– Both direction (3G ↔ 2G) operates properly in NSN and Huawei
– 3G/2G HO reliable for all vendors
Vodafone recommendations for efficient 3G -> 2G IRAT handover:– Relax voice IRAT thresholds to delay 3G to 2G HO and keep 3G voice traffic in 3G networks
– Exact values for trigger thresholds are vendor specific and depends on the site density of each operator
– To switch cell change order (CCO) off for packet or set an extreme relaxed packet IRAT threshold– Exact values for trigger thresholds are vendor specific and depends on the site density of each operator
– Option to increase pilot power. This could be at least a temporarily solution for further delay of 3G to 2G HO. (Trails have shown significant impact to 3G/2G traffic handling, e.g. VF Spain +15% and VF Germany +6% in 3G)
Conditions:3G network has sufficient capacity(utilisation is notclose to limits)
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2G/3G Traffic related interworkingIRAT Parameterisation – Recommended Thresholds
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Ranges Typical Settings CS Ec -102…-107 dBm
CS EC/Io -12….-14 dB
PS Ec -110…-115 dBm
PS EC/Io =< -14 dB Alternatively, triggers for PS could be completely switched off
Alternatively, triggers for PS could be completely switched off
Typical Observation:
CS Ec: - 103 dBmCS Ec/Io: - 14 dB
PS Ec: - 110 dBmPS Ec/Io: - 14 dB
Minimum requirements for not highly utilized 3G networks(OpCo should adapt values totheir local situation, e.g. vendors,…)
Alternative: switch triggers for PS off
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Back Up
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Screenshots of the modelThe actual version of the model can be downloaded from the best practice sharing teamroom: RDC High Level Model, a detailed description here description
In the Network base mostimportant input data are defined
The definition….
…. of the network
…. the monthly trafficper subscriber
…. the billable to busyhour traffic translation
…. the subscriber figures
…. some importantsettings, e.g. max.allowed HR
…. the mapping to thecell classification
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High Level Dimensioning, the High Level ModelNote: The model is currently available only as MS-Access 2003 version!
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Screenshots of the modelThe Fact base contains more parameter settings, more seldom changed, e.g. operator individual 16classes definition
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Screenshots of the modelThe Statistics contains more results for furtheranalysis. For instance the reasons for high loaded cells could be found here
High Level Dimensioning, the High Level Model
•C2 – Vodafone Internal•Version 1.0•VTN
•59 •Radio Dimensioning Guideline, 2G, 3G •April 2010
Screenshots of the model
The Results contains the mainoutput of the calculation
It is a ….
…. summary containingabsolute figures in termsof carrier/TRX and sitesas well as yearly figures
…. details, results per class
…. summary about the accessand transmission networkregarding a referencenetwork concept
…. the utilisation of eachradio resourceHig
h Le
vel D
imen
sion
ing
High Level Dimensioning, the High Level Model
•C2 – Vodafone Internal•Version 1.0•VTN
•60 •Radio Dimensioning Guideline, 2G, 3G •April 2010
Screenshots of the modelThe Preferences contains generalparameter settings, mainly relatedto access and transmission
Hig
h Le
vel D
imen
sion
ingScreenshots of the modelThe Help contains background information,model and input data history
High Level Dimensioning, the High Level Model
•C2 – Vodafone Internal•Version 1.0•VTN
•61 •Radio Dimensioning Guideline, 2G, 3G •April 2010
2G/3
G N
etw
ork
Util
isat
ion
2G/3G Network UtilisationWhat does utilisation mean/express
Utilisation KPIs describe resource usage reaching 100% when load exceeds 75%
DL Power
UL Noise
Codes
Channel Elements
Access Transmission
75% load (design target) = 100% ‘utilisation’
Resource loading
100% utilisation does not automatically imply capacity spend. Full investigation is needed
first
Access Transmission:Congestion in this link (connection the base station back to the RNC and core network) Leads to reduced throughput for PS services and eventually blocking for CS servicesProcessing Capacity:Within the base station there are physical limits on channel processing capacity and also on “Codes” which are used to assign 3G Radio BearersPower/Noise:Many elements formulate the overall power or “link” budget that the radio network is planned too (not least the site density). Everycall/data session uses some of this power budget, excessive load will cause congestion, degradation of customer performance and reduces coverage
Key elements in the radio network driving dimensioning and congestion
Access Transmission link bandwidth
Processing capacity in the Base Station (CEs/Codes)
Downlink power and uplink noise
Base Station
Antennas
Overall utilisation= MAX resource
Access network utilisation measures the physical resource usage…
•C2 – Vodafone Internal•Version 1.0•VTN
AUT EGY ESP GER GRE IRE ITA NZL POR ROM SUI UK
VendorNokSie E/// NokSie ALU E///
inner urban
E/// highway or
E/// ALU
CS Voice (Ec) [dBm] -104 -106 -103 -99 -101 -105 -105 -102 -107 -102 -105 -102 -105 -105 -115 -103
CS Voice (Ec/Io) [dB] -13 -13 -12 Off -14 -14 -12 -12 -13 -15 -9 -14 -13 -14 -11 -12
PS Voice (Ec) [dBm] -115 -106 -115 CCO of CCO off -115 -115 -108 CCO of CCO of-115 CCO of No h/o -105 -115 -107
PS Voice (Ec/Io) [dB] -14 -13 -18 CCO of CCO of -14 -15 -15 -14 CCO of CCO of-15 CCO of No h/o -14 -10 -13
NED
2G/3G Traffic related interworkingIRAT Parameterisation – IRAT Settings – Status Mid 2008
•April 2010•Radio Dimensioning Guideline, 2G, 3G•62
2G/3
G T
raffi
c M
anag
emen
t
Ranges Typical Settings CS Ec -102…-107 dBm
CS EC/Io -12….-14 dB
PS Ec -110…-115 dBm
PS EC/Io =< -14 dB Alternatively, triggers for PS could be completely switched off
Alternatively, triggers for PS could be completely switched off
•C2 – Vodafone Internal•Version 1.0•VTN
2G/3G Traffic related interworkingIRAT Parameterisation – Results from trial in Berlin/Germany (1/4)
•April 2010•Radio Dimensioning Guideline, 2G, 3G•63
2G/3
G T
raffi
c M
anag
emen
t
0
100
200
300
400
500
600
0 24 48 72 96 120 144
Usa
ge/[E
rlang
]
0
50
100
150
200
250
Verw
eild
auer
in 3
G [s
ec]
Bearerusage_Cv [Erlang]; KW33Bearerusage_Cv [Erlang]; KW32Cv12_duration in 3G per RAB [sec] ; KW33Cv12_duration in 3G per RAB [sec] ; KW32
Wochenverlauf (Std)
Verweildauer in 3G:106 -> 129 sec, + 22%
Voicetraffic+23%
exposure time in 3G +24%
(93 -> 115 sec)
Expo
sure
tim
e in
3G
[sec
]
weekly performance [h]
0
100
200
300
400
500
600
0 24 48 72 96 120 144
Usa
ge/[E
rlang
]
0
50
100
150
200
250
Verw
eild
auer
in 3
G [s
ec]
Bearerusage_Cv [Erlang]; KW33Bearerusage_Cv [Erlang]; KW32Cv12_duration in 3G per RAB [sec] ; KW33Cv12_duration in 3G per RAB [sec] ; KW32
Wochenverlauf (Std)
Verweildauer in 3G:106 -> 129 sec, + 22%
Voicetraffic+23%
exposure time in 3G +24%
(93 -> 115 sec)
Expo
sure
tim
e in
3G
[sec
]
weekly performance [h]
Voicetraffic+23%
exposure time in 3G +24%
(93 -> 115 sec)
Voicetraffic+23%
exposure time in 3G +24%
(93 -> 115 sec)
Expo
sure
tim
e in
3G
[sec
]
weekly performance [h]
> Goal 1 fulfilled: Maximization of 3G Voice-Usage
– 3G Voice traffic +23%
– GSM Voice traffic -3.4%
•Traffic development 3G
☺
Signal level
RSCP/ [dBm]
-98
-102
-105
‘old‘ compressed mode threshold
‘old’ IRAT HO threshold
‘new’compressed mode + IRAT HO threshold
Signal level
RSCP/ [dBm]
-98
-102
-105
‘old‘ compressed mode threshold
‘old’ IRAT HO threshold
‘new’compressed mode + IRAT HO threshold
Signal level
RSCP/ [dBm]
-98
-102
-105
‘old‘ compressed mode threshold
‘old’ IRAT HO threshold
‘new’compressed mode + IRAT HO threshold
•C2 – Vodafone Internal•Version 1.0•VTN
2G/3G Traffic related interworkingIRAT Parameterisation – Results from trial in Berlin/Germany (2/4)
•April 2010•Radio Dimensioning Guideline, 2G, 3G•64
2G/3
G T
raffi
c M
anag
emen
t
> Goal 2 fulfilled : Minimization of compressed mode activity
– Compressed mode activation -45%
•Compressed mode activity
0
20.000
40.000
60.000
80.000
100.000
120.000
140.000
160.000
180.000
21.07
.2008
23.07
.2008
25.07
.2008
27.07
.2008
29.07
.2008
31.07
.2008
02.08
.2008
04.08
.2008
06.08
.2008
08.08
.2008
10.08
.2008
12.08.2
008
14.08
.2008
16.08
.2008
18.08
.2008
20.08
.2008
22.08.2
008
24.08
.2008
26.08
.2008
Anz
ahl C
M A
ktiv
ieru
ngen
1
1,05
1,1
1,15
1,2
1,25
1,3
1,35
1,4
1,45
1,5
Verh
ältn
is C
M /
IRA
T HO
Cmactatt Isys
CM_pro_IRAT_att / Avg. ASS
CM activation
CM per IRAT HO
CompressedMode -45%
No
CM
act
ivat
ions
Rat
io C
M /
IRA
T H
O
0
20.000
40.000
60.000
80.000
100.000
120.000
140.000
160.000
180.000
21.07
.2008
23.07
.2008
25.07
.2008
27.07
.2008
29.07
.2008
31.07
.2008
02.08
.2008
04.08
.2008
06.08
.2008
08.08
.2008
10.08
.2008
12.08.2
008
14.08
.2008
16.08
.2008
18.08
.2008
20.08
.2008
22.08.2
008
24.08
.2008
26.08
.2008
Anz
ahl C
M A
ktiv
ieru
ngen
1
1,05
1,1
1,15
1,2
1,25
1,3
1,35
1,4
1,45
1,5
Verh
ältn
is C
M /
IRA
T HO
Cmactatt Isys
CM_pro_IRAT_att / Avg. ASS
CM activation
CM per IRAT HO
CompressedMode -45%
No
CM
act
ivat
ions
Rat
io C
M /
IRA
T H
O
☺
•C2 – Vodafone Internal•Version 1.0•VTN
2G/3G Traffic related interworkingIRAT Parameterisation – Results from trial in Berlin/Germany (3/4)
•April 2010•Radio Dimensioning Guideline, 2G, 3G•65
2G/3
G T
raffi
c M
anag
emen
t
> Goal 3 fulfilled : Minimization number of 3G -> 2G HO
– No IRAT HO -31%
•Minimization number of 3G -> 2G HO
0
10.000
20.000
30.000
40.000
50.000
60.000
70.000
80.000
21.07
.2008
23.07
.2008
25.07
.2008
27.07
.2008
29.07
.2008
31.07
.2008
02.08
.2008
04.08
.2008
06.08
.2008
08.08
.2008
10.08
.2008
12.08
.2008
14.08
.2008
16.08
.2008
18.08
.2008
20.08
.2008
22.08
.2008
24.08
.2008
26.08
.2008
Anza
hl IR
AT
HO
0,1
0,15
0,2
0,25
0,3
0,35
0,4
Verh
ältn
is IR
AT-
HO
/ Vo
ice-
RAB
s
Hhoalloutatt4 Cs Cb
IRAT HO att / Cv 12-RAB
IRAT HO
IRAT-HO per RAB
IRAT-HO -31%
No
of IR
AT
HO
Rat
io IR
AT
HO
/ Vo
ice
RA
Bs
0
10.000
20.000
30.000
40.000
50.000
60.000
70.000
80.000
21.07
.2008
23.07
.2008
25.07
.2008
27.07
.2008
29.07
.2008
31.07
.2008
02.08
.2008
04.08
.2008
06.08
.2008
08.08
.2008
10.08
.2008
12.08
.2008
14.08
.2008
16.08
.2008
18.08
.2008
20.08
.2008
22.08
.2008
24.08
.2008
26.08
.2008
Anza
hl IR
AT
HO
0,1
0,15
0,2
0,25
0,3
0,35
0,4
Verh
ältn
is IR
AT-
HO
/ Vo
ice-
RAB
s
Hhoalloutatt4 Cs Cb
IRAT HO att / Cv 12-RAB
IRAT HO
IRAT-HO per RAB
IRAT-HO -31%
No
of IR
AT
HO
Rat
io IR
AT
HO
/ Vo
ice
RA
Bs
☺
•C2 – Vodafone Internal•Version 1.0•VTN
2G/3G Traffic related interworkingIRAT Parameterisation – Results from trial in Berlin/Germany (4/4)
•April 2010•Radio Dimensioning Guideline, 2G, 3G•66
2G/3
G T
raffi
c M
anag
emen
t
> Goal 4 fairly fulfilled: Securing Voice quality and stability
– RAB loss ratio increase by +4%
– Drop/Erlang -17%
– laboratory study shows voice quality ‘good’ until RSCP ~ -112 dBm
•Securing Voice quality and stability
0,00%
0,10%
0,20%
0,30%
0,40%
0,50%
0,60%
0,70%
0,80%
0,90%
1,00%
21.07
.2008
23.07
.2008
25.07
.2008
27.07
.2008
29.07
.2008
31.07
.2008
02.08
.2008
04.08
.2008
06.08.2
008
08.08
.2008
10.08.2
008
12.08
.2008
14.08
.2008
16.08
.2008
18.08
.2008
20.08
.2008
22.08
.2008
24.08
.2008
26.08
.2008
P507
/ %
0
0,05
0,1
0,15
0,2
0,25
Dro
p pr
o E
rlang
P507_Cv12
Drop_Cv12/Erlang
Avg. Drop_Cv12/Erlang
Avg. P507_Cv12
Drop/Erlang -17%
RAB loss ratio_CS +4%RA
B lo
ss ra
tio_C
S[%
]
RAB loss ratio_Cv12
0,00%
0,10%
0,20%
0,30%
0,40%
0,50%
0,60%
0,70%
0,80%
0,90%
1,00%
21.07
.2008
23.07
.2008
25.07
.2008
27.07
.2008
29.07
.2008
31.07
.2008
02.08
.2008
04.08
.2008
06.08.2
008
08.08
.2008
10.08.2
008
12.08
.2008
14.08
.2008
16.08
.2008
18.08
.2008
20.08
.2008
22.08
.2008
24.08
.2008
26.08
.2008
P507
/ %
0
0,05
0,1
0,15
0,2
0,25
Dro
p pr
o E
rlang
P507_Cv12
Drop_Cv12/Erlang
Avg. Drop_Cv12/Erlang
Avg. P507_Cv12
Drop/Erlang -17%
RAB loss ratio_CS +4%RA
B lo
ss ra
tio_C
S[%
]
RAB loss ratio_Cv12
Drop/Erlang -17%
RAB loss ratio_CS +4%RA
B lo
ss ra
tio_C
S[%
]
RAB loss ratio_Cv12
•C2 – Vodafone Internal•Version 1.0•VTN
2G/3G Traffic related interworkingIRAT Parameterisation – CS VF-Spain
•April 2010•Radio Dimensioning Guideline, 2G, 3G•67
2G/3
G T
raffi
c M
anag
emen
t % Call End in 2G
15
20
25
30+6% Stay in 3G
Traffic_perRB
7580859095
100105110
+10% Voice Call Length
HHO_IRAT_Out_Decision_CS_Att
20000220002400026000280003000032000
20/0
1/20
06
27/0
1/20
06
03/0
2/20
06
10/0
2/20
06
17/0
2/20
06
24/0
2/20
06-18% HHO3G2G Voice
% Drop VOZ (Iu/Rab)
00.10.20.30.40.50.60.70.8
11/02
/2006
18/02
/2006
25/02
/2006
04/03
/2006
Drop Call not affected
•% Call End in 2G decreases 6% •CS 3G traffic increases 10%
•CS Call drops not impacted•IRAT HO attempts decreases 18%