3G Coverage Obligation Verification Methodology

Transcription

1 3G Cverage Obligatin Verificatin Methdlgy Statement Publicatin date: 9 May 2012

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3 Main Heading Cntents Sectin Page 1 Intrductin 1 2 Summary f apprach 2 3 Key parameters t be used in the SINR calculatin 4 4 Overview f the calculatin methd 5

4 Sectin 1 1 Intrductin 1.1 Ofcm published a Ntice n 2 February 2011 prpsing t make a number f variatins t the existing 2100 MHz Third Generatin Mbile Wireless Telegraphy Act licences. 1.2 Ofcm published a Statement n 20 June 2011 where we stated that we wuld vary the licences in line with ur prpsal in the Ntice subject t sme minr changes t the drafting f the licences. We als said that if the individual licensees chse t cnsent t these changes then new licences will be issued t them. 1.3 In additin we said that we wuld carry ut further wrk in cnjunctin with the mbile netwrk peratrs t reach a cnsensus regarding a cverage bligatin verificatin methdlgy. This wrk is nw cmplete and the methdlgy is utlined in this statement. 1.4 The Directin 1 requires Ofcm t revise the cverage bligatin specified in the current 3G licences shuld the Licensee request a variatin t the term f their licence. The key requirements f the revised bligatin are that by 20 June 2013, the licensee must prvide an electrnic cmmunicatins netwrk: that is capable f prviding mbile telecmmunicatins services t an area within which at least 90% f the ppulatin f the UK lives (this represents an increase frm the existing 80% ppulatin cverage bligatin in the current licences); and with a 90% prbability that users in utdr lcatins within that area can receive the service with a sustained dwnlink speed f nt less than 768 kbps in a lightly laded cell. 1.5 Fr the purpses f this ntice, we interpret lightly laded cell as fllws: a lightly laded cell has a single user demanding service with a sustained dwnlink speed f nt less than 768 kbps and the surrunding cells f the netwrk are laded t a lw level (e.g. the cmmn channels transmitting at 20% f their maximum pwer). 1.6 Belw we summarise ur apprach t mnitr and verify cmpliance with the revised bligatin. 1 The Wireless Telegraphy Act 2006 (Directins t OFCOM) Order 2010 (S.I.2010 N. 3024) which can be fund at: 1

5 Sectin 2 2 Summary f apprach 2.1 In rder t assess whether a terminal lcated at any specific lcatin can receive the minimum dwnlink speed, we cnsider that the fllwing cnditin needs t be met: the signal t interference plus nise rati (SINR) f the relevant data channel (i.e. the high speed dwnlink shared channel (HS-DSCH) fr HSDPA systems) needs t be abve a certain threshld. We set ut belw hw that threshld is t be calculated. 2.2 Our apprach is t calculate the SINR (HS-DSCH) fr a hypthetical test terminal lcated at each ppulatin pint taking int accunt signals frm the 20 clsest base sites. 2.3 The SINR threshld used t verify cmpliance with the bligatin will be -5 db. Ppulatin distributin mdel 2.4 On examinatin f the ppulatin weighted utput area centrid f the 2001 Census it was decided that the dataset is t carse a measure f ppulatin. As the utput areas get bigger, especially in rural areas, the ppulatin weighted centrid is nt a true representatin f where the ppulatin lives. 2.5 A dataset based n Ordnance Survey CdePint residential delivery pint data in cnjunctin with census data t will be used t create the ppulatin distributin. 2.6 Ppulatin will be unifrmly distributed acrss residential delivery pints within each census utput area. 2.7 Ordnance Survey CdePint data des nt cntain residential delivery pint data in Nrthern Ireland, in rder t capture the data fr all natins the enhanced dataset Gepint Plus will be used. Fr the first verificatin exercise the Gepint Plus R52 will be used. 2.8 The mst up t date full census dataset shuld be used in any assessment. At the current time and fr the first verificatin exercise this is the 2001 dataset. 2.9 Fr future cverage verificatin exercises a 1 year ntice perid will be given by Ofcm if there is t be a change in the surce data fr the ppulatin distributin used t measure cmpliance. Clutter database 2.10 A 50 metre reslutin clutter database will be used t identify the dminant clutter designatin at the ppulatin pint. The Ofcm Infterra clutter dataset has 10 clutter categries that will be mapped t the required Urban, Suburban and Open clutter designatins as utlined in Table

6 Categry Descriptin Clutter Designatin 1 Dense Urban Urban 2 Urban Urban 3 Industry Suburban 4 Suburban Suburban 5 Village Suburban 6 Parks/Recreatin Open 7 Open Open 8 Open in Urban Open 9 Frest Open 10 Water Open Prpagatin Mdel Table 2.1 Infterra clutter cde mapping 2.11 A median path lss will be calculated using the Extended Hata 2 Mdel Lcatin variatin can be cnsidered t be apprximately a lgnrmal distributin with zer mean. 90% lcatin prbability will be included in the calculatin using a standard deviatin σ L derived frm equatin 32 in Annex 5 f Recmmendatin ITU- R P σσ LL = KK + 1.3llllll 10 (ff) db with a value f K = 4.2 db fr Urban clutter and K = 3.5 db therwise. Frequency, f, is in MHz. 2 ERC Reprt 68 and ECO Seamcat User Manual at 3

7 Sectin 3 3 Key parameters t be used in the SINR calculatin 3.1 Table 3.1 cntains the key parameters t be used in the SINR calculatin, these are given fr 2100 and 900 MHz. Ofcm des nt anticipate 1800 MHz being used fr HSPA services at this time, shuld assessment including 1800 MHz be required suitable parameters will be set. Parameter Unit 2100 MHz 900 MHz UE Nise figure db 8 10 UE Antenna gain db 0 0 HS-DSCH Pwer % Pilt pwer % Other cmmn CH % Lightly laded neighbur % Bdy/rientatin lss db Table 3.1 Key parameters fr 2100 and 900 MHz 3.2 Theretical radiatin patterns taken frm 3GPP TR tuned t the supplied antenna beamwidths will be applied in the SINR calculatin. Azimuth pattern: AA HH (φφ) = mmmmmm 12 φφ φφ 3dddd 2, AA mm Elevatin pattern: AA VV (θθ) = mmmmmm 12 θθ θθ tttttttt 2, SSSSSS θθ vv 3dddd The values f ϕ 3dB, θ 3dB and θ tilt are supplied inputs, A m = 25 db and SLA v = 20 db. 4

8 Sectin 4 4 Overview f the calculatin methd 4.1 Fr each peratr the calculatin wuld prceed alng the fllwing lines, illustrated in figure 4.1: the peratr supplies data fr each 3G site in its netwrk. This data culd include all r sme f the fllwing - supplemented (fr certain, nn critical, parameters) by default values if necessary: lcatin (6 figure NGR); height abve grund level (metres); number f sectrs; fr each sectr; frequency carrier(s) bresight directin (degrees east f nrth); bresight gain (dbi); hrizntal 3 db beamwidth (degrees); vertical 3 db beamwidth (degrees); cmbined mechanical and electrical dwntilt (degrees); maximum transmit pwer (int antenna) r EIRP (dbm); fr each ppulatin data pint: the nearest 20 base statins t the ppulatin pint are identified; fr each sectr f the nearest base statins identified in the previus step, the dwnlink pwer that wuld be received by a terminal 1.5 metres abve grund level at the ppulatin pint lcatin is calculated; a theretical antenna radiatin pattern tuned t the beamwidths prvided in the input data is applied t each sectr; the base statin sectr prviding the highest received pwer is designated as the serving sectr; nn-serving sectrs are assumed t be transmitting at 20% f their maximum pwer (i.e. they are lightly laded); a SINR f HS-DSCH distributin is created using a Mnte Carl prcess calculated by assuming 0.5 lcatin variability crsscrrelatin between the serving and nn-serving sites; 5

9 if the 90% percentile f the resultant SINR distributin is calculated t be greater than r equal t the -5dB threshld the ppulatin pint is deemed t be served. if the first carrier des nt serve the pint the next and subsequent carriers (until all prvided carriers are exhausted) will be assessed in turn. If ne f them meets the criteria in the pints abve the ppulatin pint is deemed t be served. the ppulatin assciated with the served ppulatin pint is added t the cumulative ppulatin served. Once the value f cumulative ppulatin served is greater than r equal t 90% f the UK ppulatin, the licence cnditin will be deemed t have been met and the verificatin prcess is stpped 6

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11 Main Heading Inputs: Ppulatin pint data: Lcatin (NGR) Ppulatin Clutter Transmitter data: Frequency carrier(s) Lcatin (NGR) Height Number f Sectrs EIRP Antenna parameters Hrizntal beamwidth Vertical beamwidth Azimuth Tilt Receiver data: Receiver Sensitivity Height Antenna gain Prcess: If available Select Ppulatin Pint Select Frequency Select transmitter lcatins within 15 km < 5 >= 5 Calculate path lss frm lcatin t ppulatin pint Calculate Wanted signal level Calculate SINR <Th Next Frequency If available r Pint NOT served Next Pint Select 5 clsest transmitter lcatins Calculate Interference signal level > Th Pint served Next Pint Prpagatin Mdel Extended Hata plus shadw fading margin Threshld Level (Th) SINR = -5 db Figure 4.1 Prcess verview