Network QualityTechnology for executives, Moscow - 13 September 2004 Author: Morten Raaum Presenter: Hans Myhre

Network Quality, as perceived by customerCoverageCapacitySpeech qualityServices qualityCustomer care..

GSM in the fieldBTSBTSBTSBTSTo BSC / MSCTo BSC / MSCTo BSC / MSCTo BSC / MSCHandoverHandover

Some practical experiences..No network access (= no Telenor in the display)Lack of coverageNetwork overload situation (users barred from access)Network failure.3 beeps/3-tone beeps at call setupBlocking/error situations somewhere in the networkUser error (e.g. non-existent number)Poor speech qualityMarginal coverageInterference between base stationsDropped callPoor quality of radio linkBlocking in target cell (moving mobile, handover situation)Network failure (transmission)The mobile is the weakest link in the chain:Mass production units Internal antenna Increased software and processing complexity (WAP/GPRS/HSCSD/games&features)

GSM in the fieldBTSBTSBTSBTSTo BSC / MSCTo BSC / MSCTo BSC / MSCTo BSC / MSCHandoverDropped callPoor speech qualityHandover to non-optimal cellNo traffic channels available

How is Network Quality monitored by the operator?CoverageMeasurements by technical staff. Test telephone + laptop.Measurements by remotely controlled test systems (installed in bus, taxi etc). Customer complaints and performance stats as input.CapacityNetwork Maintenance Center / Operations centerThe network counts # of events (pos./neg.) Post processing in Performance Management tool.Tools for prognosis on capacity needs vs. required quality of the network (Grade of Service)

How is Network Quality monitored by the operator?Speech qualityThe network counts Dropped calls and to some extent report on speech qualityMeasurements by remotely controlled test systems / tech.staff.

Services qualityServices are built up by combining equipment and softwareExternal tools needed to ensure quality of deliveryCorrect content / Response time3rd party content delivery3rd party Service Level Agreements (SLA)

Capacity and quality a trade off at a given funding

Capacity in the GSM radio network Base station with antennas connected in a mastBTS contains a number of TRX based on the need for capacity.BTS cabinetTRXTRXTRX

Radio network capacityBuilding blocks for capacity at the base stations: TRX8 channels that are used for signalling (SMS, suppl.services etc) and speech/data.

Call duration -> Erlang1 Erlang = 1 hour of speech for 1 userCall duration 90 sec: 90s / 3600s = 0,025 Erl = 25 mErl I.e. 1 Erlang: 40 calls of 90 seconds each. (1 Erl = 40 x 25 mErl)

Theoretical capacity: Erlangs model and chosen Grade of Service.GoS (%) Number of call attempts that may meet blocking in a busy hour.Typical values used: 2-5%

Example, GoS=2%1 TRX7 speech channels2.9 Erlang 41%2 TRX15 speech channels 9.0 Erlang 60%3 TRX22 speech channels 14.9 Erlang 68%4 TRX30 speech channels 21.9 Erlang 73%

Radio network capacityBase station configuration example:

3 TRXes, Omni directional cell1 cell with 3 TRX, GoS=2%: Capacity = 14.9 Erl90 sec call duration (25mErl)14.9 / 0.025 = 596 calls in a busy hour (theoretical max!)

If we accept higher blocking figures we can carry more traffic with less customer satisfaction.5% GoS used in this example => 17.1 Erl capacity => 684 calls (+15%)

Base station configuration example:

3 TRXes, Sectorised 1/1/1.3 cells with 1 TRX each: Capacity = 3 x 2,9 Erl = 8,7 Erl90 sec call duration 8,7 / 0,025 = 348 calls in a busy hour

If we accept higher blocking figures we can carry more traffic with less customer satisfaction.5% GoS used in this example => 11.1 Erl capacity => 444 calls (+28%)

Radio network capacity

Frequency planningRe-use of GSM channels is necessary. In this example a frequency is re-used in every 12th cell => reuse factor 12

Resource: Frequency spectrumSpectrum size strongly affect base station roll out.Re-use of GSM channels is necessary. 1 TRX use 1 GSM channel

Example, Malaysia: 24.8 MHz => 124 GSM channels# of TRX per cell: >6. Good capacity per base station (xx Erlang).Example, Russia:4 MHz => 20 GSM channelsMaximum ~1,5 TRX per cell = a denser base station network will be needed for serving increasing traffic (xx Erlang)Good radio/frequency planning and use of smart features enables a tight re-use of GSM channelsPower control Mobile and BTS adjust their output power as low as possible, adjustment 2 times per sec.Discontinuous Transmission (DTX) Mobile and BTS only transmit when user actually speak. (User benefit: less power consumption)Frequency hopping Mobile and BTS jump from GSM channel to GSM channel (480ms), less affected by interference.

Area= 50km2Population= 1 MSubscribers= 346k15 mErl/subTraffic= 5190 Erl

Spectrum vs. investmentsCapacity caseMalaysia case..6TRX/cell= 34,6 Erl/cell900TRX, 150 cells and 50 BTS needed

Russia case..1,5 TRX/cell= 5,8 Erl/cell1343TRX, 895 cells and 299 BTS needed

We need 6 times as many sites for capacity reason!

For illustration purpose only the conclusions and calculations are simplified

Spectrum vs. investments-basestation equipment cost onlyEquipment prices, MalaysiaBTS 1/1/1 + ext.cab42.000$TRX 6.000$

Equipment prices, RussiaBTS 1/1/130.000$TRX 6.000$

For illustration purpose only the conclusions and calculations are highly simplifiedTransmission, BSC and software cost left out.

Sheet1

BTS 1/1/14200030,000

TRX6,000

Malaysia case..Russia case..

UnitsCapexUnitsCapex

BTS502,100,0003009,000,000

TRX7504,500,000150900,000

Sum6,600,0009,900,000

50%

Sheet2

Sheet3

Network Quality,some KPIsMinutes per dropped callSummary of all traffic minutes divided by number of dropped calls during a period of time (e.g. Week/month) Typical values: 50-150 minutes.

Blocking/CongestionCall attempts that meet blocking, all resources are occupied.The network is dimensioned to meet a certain traffic level in the busy hour. Typical dimensioning values (GoS): 2 - 5 % Typical values measured in the networks: 0 - 50+ %

Network Quality, some KPIsNetwork UtilisationAbout 22% of the cells in the network are utilised > theoretical max = customers experience more blocking than acceptable in these cells!

Blocked calls

200500

200.75520

201.5480

202.25470

203490

203.75465

204.5510

205.25500

206500

206.75505

207.5490

208.25450

209440

210.5510

212505

213.5500

215420

216.5405

218425

219.5400

221405

222.5395

223.25375

224375

224.75355

225.5335

226.25320

227325

227.75335

228.5310

230.75300

232.5245

233.25205

234220

234.75195

235.5190

236.25185

237.75175

239.25180

240.75175

&A

Page &P

Target, blocking cells (5%)

Blocking cells

Week

# of cells

Blocking cells

MPD

65952000000

54952100000

54952150000

52952140000

49952180000

48952230000

49952240000

47952240000

49952260000

51952255000

51952266000

57952267000

58952269000

59952300000

60952310000

60952350000

61952280000

61952250000

67952360000

67952360000

66952370000

68952370000

67952385000

75952390000

75952390000

76952400000

77952410000

74952420000

76952450000

78952430000

77952440000

78952450000

78952720000

80952710000

79952725000

78952730000

79952740000

79952760000

79952755000

80952770000

&A

Page &P

Minutes Per Dropped call

Target MPD

Total traffic (call minutes)

Minutes

Total traffic (weekly)

Minutes per drop vs total traffic

Rollout 2001

15128700

2017131150

25221816100

30272321152

35322826203

403733312516

454538363028

505243413535

556048464040

606153514542

656558565048

706863615553

757568666054

808073716554

858378767060

908883817571

959388888078

1009893928584

10510398969091

1101081031019594

11511310810610096

120118113111105102

125123118116110108

130128123121115113

135133128126120118

140138133131125123

145143138136130128

150148143141135133

155153148146140138

160158153151145143

165163158156150148

170168163161155153

175175168167160158

180187173175165163

185190178180170168

190205183184175170

195208188188180172

200210193195185184

205210198200190192

210210203204195200

Lease contract signed, planned

Lease contract signed, actual

Ready for installation, planned

Ready for installation, actual

Ready for service, planned

Ready for service, actual

Rollout 2001

Weekly data

Week12345678910111213141516171819202122232425262728293031323334353637383940

Cells4000401540304045406040754090410541204135415041654180421042404270430043304360439044204450446544804495451045254540455545704615465046654680469547104725475547854815

Target, blocking cells (5%)200201202202203204205205206207208208209211212214215217218220221223223224225226226227228229231233233234235236236238239241

Blocking cells500520480470490465510500500505490450440510505500420405425400405395375375355335320325335310300245205220195190185175180175

Minutes Per Dropped call65545452494849474951515758596060616167676668677575767774767877787880797879797980

Target MPD95959595959595959595959595959595959595959595959595959595959595959595959595959595

Total traffic (call minutes)2000000210000021500002140000218000022300002240000224000022600002255000226600022670002269000230000023100002350000228000022500002360000236000023700002370000238500023900002390000240000024100002420000245000024300002440000245000027200002710000272500027300002740000276000027550002770000

RollOut2001

Lease contract signed, planned1520253035404550556065707580859095100105110115120125130135140145150155160165170175180185190195200205210

Lease contract signed, actual121722273237455260616568758083889398103108113118123128133138143148153158163168175187190205208210210210

Ready for installation, planned8131823283338434853586368737883889398103108113118123128133138143148153158163168173178183188193198203

Ready for installation, actual7111621263136414651566166717681889296101106111116121126131136141146151156161167175180184188195200204

Ready for service, planned05101520253035404550556065707580859095100105110115120125130135140145150155160165170175180185190195

Ready for service, actual0002316283540424853545460717884919496102108113118123128133138143148153158163168170172184192200

Cell Utilization

14510040

14510040

14410040

14410040

14410040

14310040

14310040

14310040

13510040

13110040

13010040

13010040

12510040

12310040

12210040

12110040

12110040

11510040

11510040

11310040

11010040

10810040

10510040

10310040

10210040

10110040

10010040

9910040

9710040

9510040

9410040

9010040

8510040

8410040

8310040

8010040

7810040

7610040

7410040

7210040

7010040

6710040

6410040

6110040

5810040

5610040

5410040

5410040

5410040

5410040

5310040

5310040

5210040

5010040

5010040

4910040

4910040

4910040

4910040

4910040

4810040

4810040

4810040

4510040

4310040

4310040

4210040

4210040

4110040

3810040

3710040

3710040

3610040

3510040

3410040

3210040

3210040

3210040

3010040

3010040

3010040

2910040

2910040

2810040

2710040

2610040

2510040

2510040

2510040

2410040

2210040

2110040

2110040

2010040

2010040

1910040

1910040

1810040

1710040

1710040

1710040

1610040

1610040

1610040

1510040

1510040

1410040

1410040

1410040

1310040

1310040

1310040

1210040

1110040

810040

810040

710040

710040

610040

510040

510040

510040

510040

510040

410040

310040

210040

210040

210040

Utilization

Target 100%

Target 40%

Cell utilization distribution

Utilization (%)

Cell utilization

Snapshot traffic

UtilizationTarget 100%Target 40%129Cell utilization distribution

1451004010.8 %0.8 %

1451004010.8 %1.6 %

1441004010.8 %2.3 %

1441004010.8 %3.1 %

1441004010.8 %3.9 %

1431004010.8 %4.7 %

1431004010.8 %5.4 %

1431004010.8 %6.2 %

1351004010.8 %7.0 %

1311004010.8 %7.8 %

1301004010.8 %8.5 %

1301004010.8 %9.3 %

1251004010.8 %10.1 %

1231004010.8 %10.9 %

1221004010.8 %11.6 %

1211004010.8 %12.4 %

1211004010.8 %13.2 %

1151004010.8 %14.0 %

1151004010.8 %14.7 %

1131004010.8 %15.5 %

1101004010.8 %16.3 %

1081004010.8 %17.1 %

1051004010.8 %17.8 %

1031004010.8 %18.6 %

1021004010.8 %19.4 %

1011004010.8 %20.2 %

1001004010.8 %20.9 %

991004010.8 %21.7 %

971004010.8 %22.5 %

951004010.8 %23.3 %

941004010.8 %24.0 %

901004010.8 %24.8 %

851004010.8 %25.6 %

841004010.8 %26.4 %

831004010.8 %27.1 %

801004010.8 %27.9 %

781004010.8 %28.7 %

761004010.8 %29.5 %

741004010.8 %30.2 %

721004010.8 %31.0 %

701004010.8 %31.8 %

671004010.8 %32.6 %

641004010.8 %33.3 %

611004010.8 %34.1 %

581004010.8 %34.9 %

561004010.8 %35.7 %

541004010.8 %36.4 %

541004010.8 %37.2 %

541004010.8 %38.0 %

541004010.8 %38.8 %

531004010.8 %39.5 %

531004010.8 %40.3 %

521004010.8 %41.1 %

501004010.8 %41.9 %

501004010.8 %42.6 %

491004010.8 %43.4 %

491004010.8 %44.2 %

491004010.8 %45.0 %

491004010.8 %45.7 %

491004010.8 %46.5 %

481004010.8 %47.3 %

481004010.8 %48.1 %

481004010.8 %48.8 %

451004010.8 %49.6 %

431004010.8 %50.4 %

431004010.8 %51.2 %

421004010.8 %51.9 %

421004010.8 %52.7 %

411004010.8 %53.5 %

381004010.8 %54.3 %

371004010.8 %55.0 %

371004010.8 %55.8 %

361004010.8 %56.6 %

351004010.8 %57.4 %

341004010.8 %58.1 %

321004010.8 %58.9 %

321004010.8 %59.7 %

321004010.8 %60.5 %

301004010.8 %61.2 %

301004010.8 %62.0 %

301004010.8 %62.8 %

291004010.8 %63.6 %

291004010.8 %64.3 %

281004010.8 %65.1 %

271004010.8 %65.9 %

261004010.8 %66.7 %

251004010.8 %67.4 %

251004010.8 %68.2 %

251004010.8 %69.0 %

241004010.8 %69.8 %

221004010.8 %70.5 %

211004010.8 %71.3 %

211004010.8 %72.1 %

201004010.8 %72.9 %

201004010.8 %73.6 %

191004010.8 %74.4 %

191004010.8 %75.2 %

181004010.8 %76.0 %

171004010.8 %76.7 %

171004010.8 %77.5 %

171004010.8 %78.3 %

161004010.8 %79.1 %

161004010.8 %79.8 %

161004010.8 %80.6 %

151004010.8 %81.4 %

151004010.8 %82.2 %

141004010.8 %82.9 %

141004010.8 %83.7 %

141004010.8 %84.5 %

131004010.8 %85.3 %

131004010.8 %86.0 %

131004010.8 %86.8 %

121004010.8 %87.6 %

111004010.8 %88.4 %

81004010.8 %89.1 %

81004010.8 %89.9 %

71004010.8 %90.7 %

71004010.8 %91.5 %

61004010.8 %92.2 %

51004010.8 %93.0 %

51004010.8 %93.8 %

51004010.8 %94.6 %

51004010.8 %95.3 %

51004010.8 %96.1 %

41004010.8 %96.9 %

31004010.8 %97.7 %

21004010.8 %98.4 %

21004010.8 %99.2 %

21004010.8 %100.0 %

Sheet3

TRXTCHCapacity (2%)Max util.Kap.kning

172.91.550%

21596.066%210%

32214.8511.980%

43021.918.484%

53728.2525.189%

64535.631.990%

Morten Raaum:Based on theory of max utilization of last TRX = 50% for a network.

Technical KPIsPSTNAccess network OSSCore network OSSTechnicalKPIsFinancialMarketHRTechnicalBenchmarkingReport

......................................................BTSBSCMSCMSCMSCMSC

Network Quality, challengesHow to measure customer perceived quality?Unmanned active measurement units.New and advanced servicesFast development and deployment of new services.Increased complexity, both for network and mobile.3.party content providersTimeout... Not available... Service Level Agreements. How do you know what is delivered?New and advanced measurement systems for test&monitoring.RoamingHow well are we able to keep foreign roamers in our network and how are our roamers abroad doing?Advanced measurement systems (signalling) for test&monitoring.

EnvironmentBase station location: Aim to minimise the effect of masts and antennas on the local environment.

Trndelag theatre

Tree-mounted antenna..

Antenna

Vindern Typical antenna-installation in a city environment

Mini-BTS mounted on a pole by the fjord

Thank you for your attention!

Additional slides

Telenor Mobile, Operations&TechnologyMorten Raaum

Base stations in Kaliningrad500.000 inhabitants19 base stations

Which cell covers where in Kaliningrad?

CAPEX reporting, Enterprise Reporting input form

Technical indicators,Enterprise Reporting input form

MH-NETTRAF_01

Telenor mHorizonForm

Network & TrafficMH-NETTRAF_01

Company CodeCompany NamePeriodTransaction typeCurrencyLast periodDateTime

31VimpelCom203ActualUSD 000s20223.04.200211:49:25

GSM CORE NETWORK

Number of MSC (cum.)

MSC CPU load > 65 %

Availability, IN

Availability, VMS

Availability, SMSC

GSM RADIO ACCESS NETWORK

Number of Cell Sites (cum.)

Total number of cells

Total number of TRX

Call Setup Success Rate

Congestion, number of cells with > 5% congestion

Call minutes per dropped call (MDP)

Theoretical capacity of radio network

Busy hour traffic, for all cells accumulated

TRANSMISSION

BSC-BTS transmission lines, % own lines

Core network transmission lines, % own lines

COVERAGE

Coverage population GSM/GPRS (%)

Coverage geography GSM/GPRS (%)

Coverage population UMTS(%)

Coverage geography UMTS (%)

Technical information as defined in Enterprise Reporting (1)

GSM CORE NETWORK

Number of MSC (cum.)

No. of mobile switches in the network

MSC CPU load > 65 %

% of MSCs in the network with CPU load > 65% in Busy Hour. (Central Processing Unit)

Availability, IN

% Up-time vs max possible time pr period (Intelligent Network nodes)

Availability, VMS

% Up-time vs max possible time pr period (Voice Mail System)

Availability, SMSC

% Up-time vs max possible time pr period (SMS Centre)

TRANSMISSION

BSC-BTS transmission lines, % own lines

Relationship between: Number of own transmission links/legs used for BSC-BTS connections vs. total no of transmission links BSC-BTS (own +leased lines).

Core network transmission lines, % own lines

Relationship between: Number of own transmission links/legs used for core network connections vs. total no of transmission links in the core network (own +leased lines). Core network transmission links: BSC - Core, Inter-Core, Core POI (Point of Interconnect)

COVERAGE

Coverage population GSM/GPRS (%)

Percentage of population in the licensed area that is covered by the carriers network

Coverage geography GSM/GPRS (%)

Geographical area covered by the network as a percentage of the licensed area

Coverage population UMTS(%)

Percentage of population in the licensed area that is covered by the carriers network

Coverage geography UMTS (%)

Geographical area covered by the network as a percentage of the licensed area

Technical information as defined in Enterprise Reporting (2)

GSM RADIO ACCESS NETWORK

Number of Cell Sites (cum.)

Total number of sites with GSM radio equipment at the end of the period. A site location with 900 and 1800 equipment counts as one.

Total number of cells

Total number of cells in the GSM network.

Total number of TRX

Total number of TRX in the GSM network

Call Setup Success Rate

Using data for 3 busiest hours of last week of period (as for K41240):

(Call setup attempts Unsuccessful setups) / Call setup attempts.

Calculation based on counters from the BSS network (i.e. Successful call setup = TCH seizure. TCH->TCH handovers excluded). Unsuccessful setups => RF-failures, network failures, blocking

Congestion, number of cells with > 5% congestion

Number of cells reporting >5% congestion on traffic channels during last week of period.

Call minutes per dropped call (MDP)

Using data for whole last week of period:

= (Accumulated Erlang traffic per cell)*60/ No. of dropped calls

OR = (Accumulated call minutes for all cells)/No. of dropped calls

Theoretical capacity of radio network

Using Erlang B formula:

Calculate the theoretical capacity of the total radio network by summing Erlang figures (theoretical capacity at planned GoS) of each cell. Capacity figure to be calculated at end of last week of period. (E.g. 1 cell with 2 TRX = 14 TCH at 3%GoS=> 8.8 Erlang)

Busy hour traffic, for all cells accumulated

Using last week of period:

Sum of individual Busy Hour traffic (Erlang) for each cell in the radio network.

Use mean value of 3 busiest hours as Busy Hour traffic per cell (3 different days in the week).

GSM network overviewBSCPOIGSM Core networkGSMAccessnetworkFixednetworkTCE

***Scale!!In a static network, the capasity and quality balance. That means that if the capasity should increase, the quality will decrease.

We cannot accept that. We want it both!By utilising new functionality and contioniously restructuring the network we are able to both increase the quality and the capasity!!**15mErl (10%BH, 25days) => 225 AMPU*Public demand to minimize the imapct of BTS-installations

Most of the cases, the delta cost between a normal site and an environmently friendly site is very low.

I have no proof to claim that we are best in the word when it comes to this, but we surely are among the leading operators in this aspect. I have not seen any operators that in such a scale focus on this.

But this is good investments- it gets us public good-will, and it surely makes the site aqusition both much easier and probably a factor in keeping the rent down..*Dummy antennas to make symmetry.The architect found that the antennas could be a part of the buildings design..Theatre is an architectural very nice building*This is an environment that is very critical. Only private High class villas and few public-buildings or offices!Then we have to use our imaginaten and find a solution.****GSM Core network data: Monthly inputs/reporting by the operatorsTransmission and Coverage data: Quarterly reports*GSM RAN data: Monthly reporting by the operators.