Network Quality 130218114136
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Transcript of Network Quality 130218114136
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Network QualityTechnology for executives, Moscow - 13 September 2004 Author: Morten Raaum Presenter: Hans Myhre
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Network Quality, as perceived by customerCoverageCapacitySpeech qualityServices qualityCustomer care..
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GSM in the fieldBTSBTSBTSBTSTo BSC / MSCTo BSC / MSCTo BSC / MSCTo BSC / MSCHandoverHandover
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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)
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GSM in the fieldBTSBTSBTSBTSTo BSC / MSCTo BSC / MSCTo BSC / MSCTo BSC / MSCHandoverDropped callPoor speech qualityHandover to non-optimal cellNo traffic channels available
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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)
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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)
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Capacity and quality a trade off at a given funding
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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
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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%
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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%)
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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
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Frequency planningRe-use of GSM channels is necessary. In this example a frequency is re-used in every 12th cell => reuse factor 12
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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.
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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
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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
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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+ %
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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.
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Technical KPIsPSTNAccess network OSSCore network OSSTechnicalKPIsFinancialMarketHRTechnicalBenchmarkingReport
......................................................BTSBSCMSCMSCMSCMSC
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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!
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Additional slides
Telenor Mobile, Operations&TechnologyMorten Raaum
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Base stations in Kaliningrad500.000 inhabitants19 base stations
-
Which cell covers where in Kaliningrad?
-
CAPEX reporting, Enterprise Reporting input form
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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.