Dimensioning of WCDMA radio network subsystem for determining optimal configurations

Transcription

1 Dimensioning of WCDMA radio network subsystem for determining optimal configurations Master s Thesis, Jarno Toivonen Nokia Networks Supervisor: Prof. Sven-Gustav Häggman 1 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen

2 Agenda Background Research problem Definitions Review of prior research Simulations Conclusions 2 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen

3 Background Strategic intent to rationalise and limit the number of configurations to the optimum Gained benefits in supply logistics shorter lead times in delivery reduced inventories and obsolescence risk reduced costs during the network life cycle in O&M, spares, etc. higher margin for the supplier, lower OPEX for the operator However, by limiting the variety of HW elements of different properties, the risk of impoverishing the offerings portfolio increases and the costperformance ratio of the overall network is compromised resulting in less competitive solutions 3 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen

4 Research problem Triangular framework where the configurations are interconnected with the achievable network performance and resulting cost The challenge is to find limited number of cost efficient configurations that meet the defined performance requirements Configuration Cost effects in the rollout Network performance: Coverage, capacity & quality 4 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen

5 Definitions The scope of research includes base station configurations and access network transmission The number and configuration of base stations drive both the performance and cost of the overall network Configuration refers to an assembly of base station structural elements, antenna system, and transmission equipment Costs are considered as configurations characteristic impact on the required CAPEX in the rollout 5 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen

6 Review of prior research (1/2) BTS site sectorisation increases offered capacity and coverage probability, also lower transmit powers are possible. However, for a cluster of cells increasing other to own cell interference i and SHO overhead limit the optimal sectorisation Best performing site types in macro cellular environment * : 3-sector 65 3dB antenna beam width 6-sector 33 3dB antenna beam width In addition comparisons include 2-sector site (in particular for highway coverage) 4-sector site Impact of site solutions SRC** and MHA***, and also ROCs are examined Generally single layer macro cellular network the most cost efficient for rollout * Source: Wacker et al.: The Impact of Base Station Sectorisation on WCDMA Radio Network Performance, IEEE VTC 1999 ** Source: Holma, Tölli: Simulated and Measured Performance of 4-branch Uplink Reception in WCDMA, Paper for IEEE VTC 2001 *** Source: Cooreman: Masthead Amplifier (MHA) Benefit, Network Planning Belgium, February 2001, Nokia Networks 6 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen

7 Review of prior research (2/2) Currently two-thirds of access network transmission implemented with microwave radio* Fast and cost-efficient rollout Depending on link length and how competitive prices are locally, also copper/leased lines may be the underlying media Fibre practically only in core, although the share of fibre expected to grow along with data traffic increase and all-ip Tree and chain topologies most common in GSM, loops for high capacity and important links** GSM CT TDM-based, whereas ATM specified as WCDMA transport technology Operator decision between IMA/fractional E1 and ATM network * Source: Whitepaper: Microwave Radio Network Planning in 3G, 2001, Nokia Networks ** Source: Törmä: Cellular Access Network, Planning Aspects of 3G Networks, Merito Forum Seminar, April NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen

8 8 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen Simulations

9 The performance of each configuration measured by the required number of sites in the three network scenarios Reference for morphology classes and demographics is Helsinki/Espoo Formulation of simulation cases 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Low asymmetry speech oriented traffic with low penetration Low asymmetry speech oriented traffic with high penetration 300km 2 service area: Subs./km 2 NRT data RT data Speech Medium asymmetry data oriented traffic with high penetration Urban 30% Suburban 10% Rural 35% Higher cell loading (network maturity) Dense urban 20% Road 5% 9 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen

10 Traffic scenario 1.1 Low asymmetry speech oriented traffic with low penetration MHA has great importance against thermal noise in AWGN channel SRC & MHA together ensure high performance for 3-sector site Triple-mode GSM/EDGE/WCDMA cost efficient config 6-sector not recommended in low loading scenario (uplink load less than 10%) Configs UL load limited, thus low TX powers % 10 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen +125% Required number of sites 3-sector SRC ul + MHA basic 3-sector + MHA GSM/EDGE co-site 5W + MHA GSM/EDGE co-site 8W + MHA basic 3-sector (50%) & 3-sector SRC ul + MHA (50%) GSM/EDGE co-site 5W (50%) & 1+1 ROC 20W (50%) 6-sector 20W 2*(1+1) ROC 20W 2*(1+1) ROC 40W 3*(1+1) ROC 20W 3*(1+1) ROC 40W basic 3-sector (60%) & 1+1 ROC 20W (40%) 3-sector SRC ul 1-omni 5W basic 3-sector (30%) & 6-sector 20W (70%) basic 3-sector (30%) & 3*(1+1) ROC 20W (70%) basic 3-sector (50%) & basic 3-sector + MHA (50%) basic 3-sector (50%) & 2*(1+1) ROC 20W (50%) GSM/EDGE co-site 5W (50%) & 3-sector SRC ul (50%) 1+1 ROC 20W ROC 20W ROC 40W basic 3-sector 20W ROC 20W basic 3-sector (50%) & GSM/EDGE co-site 5W (50%) GSM/EDGE co-site 5W GSM/EDGE co-site 8W basic 3-sector (80%) & omni fill-in site 5W (20%)

11 Traffic scenario 1.2 Low asymmetry speech oriented traffic with high penetration 3-sector site with SRC & MHA clearly the best alternative Top four configs utilise two or three carriers per sector impact of available bandwidth on the operator s business case ROCs run out of capability to meet rising loads, uplink load at around 30-40% 11 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen % +104% +519% ROC 20W 3*(1+1) ROC 20W Required number of sites 3-sector SRC ul + MHA basic 3-sector + MHA 6-sector 20W 3-sector SRC ul basic 3-sector (50%) & 3-sector SRC ul + MHA (50%) basic 3-sector (30%) & 6-sector 20W (70%) basic 3-sector (60%) & 1+1 ROC 20W (40%) basic 3-sector (50%) & basic 3-sector + MHA (50%) GSM/EDGE co-site 5W (50%) & 3-sector SRC ul (50%) GSM/EDGE co-site 8W (50%) & 3-sector SRC ul (50%) basic 3-sector (30%) & 3*(1+1) ROC 20W (70%) basic 3-sector (50%) & 2*(1+1) ROC 20W (50%) 2-omni 40W basic 3-sector 20W basic 3-sector (50%) & GSM/EDGE co-site 5W (50%) GSM/EDGE co-site 5W GSM/EDGE co-site 8W basic 3-sector (80%) & omni fill-in site 5W (20%) GSM/EDGE co-site 8W + MHA ROC 20W GSM/EDGE co-site 5W + MHA GSM/EDGE co-site 5W (50%) & 1+1 ROC 20W (50%) 3*(1+1) ROC 40W 2*(1+1) ROC 40W ROC 40W 1+1 ROC 20W 2*(1+1) ROC 20W

12 Traffic scenario 2 Medium asymmetry data oriented traffic with high penetration Configs TX power limited Transmit diversity, i.e. SRC dl, would drive the site count even lower 6-sector config s capacity assets fully used and therefore it is a valid alternative in targeted urban and suburban areas, where traffic is expected to concentrate and grow rapidly, or as a mirco cellular layer for hot spots % +100% 12 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen +824% ROC 20W 3*(1+1) ROC 20W Required number of sites 3-sector SRC ul + MHA basic 3-sector + MHA basic 3-sector (50%) & 3-sector SRC ul + MHA (50%) 3-sector SRC ul 6-sector 20W basic 3-sector (60%) & 1+1 ROC 20W (40%) basic 3-sector (30%) & 6-sector 20W (70%) basic 3-sector (50%) & basic 3-sector + MHA (50%) basic 3-sector (50%) & 2*(1+1) ROC 20W (50%) GSM/EDGE co-site 5W (50%) & 3-sector SRC ul (50%) GSM/EDGE co-site 8W (50%) & 3-sector SRC ul (50%) basic 3-sector 20W basic 3-sector (50%) & GSM/EDGE co-site 5W (50%) 3-omni 40W basic 3-sector (30%) & 3*(1+1) ROC 20W (70%) basic 3-sector (80%) & omni fill-in site 5W (20%) GSM/EDGE co-site 8W GSM/EDGE co-site 5W GSM/EDGE co-site 8W + MHA ROC 20W GSM/EDGE co-site 5W + MHA GSM/EDGE co-site 5W (50%) & 1+1 ROC 20W (50%) 2*(1+1) ROC 40W 3*(1+1) ROC 40W ROC 40W 1+1 ROC 20W 2*(1+1) ROC 20W

13 Site count cost per site Traffic scenario 1.1 Cost-performance analysis Overall RAN Configuration Number of sites cost impact 1. 3-sector triple-mode 5W + MHA % 2. 3-sector SRC ul + MHA % 3. 3-sector ROC % 4. Basic 3-sector + MHA % 5. 3-sector SRC ul % 6. 3-sector triple-mode 5W % 7. Basic 3-sector % 8. 6-sector % Traffic scenario 1.2 Overall RAN Configuration Number of sites cost impact 1. 3-sector SRC ul % 2. 3-sector triple-mode 5W % 3. Basic 3-sector + MHA % 4. Basic 3-sector % 5. 3-sector SRC ul + MHA % 6. 6-sector % 7. 3-sector ROC % 13 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen

14 Transmission capacity development In the likely rollout scenario 1.1 relatively low capacities per BTS Co-siting possible upon an existing topology and TDMbased CT network 2 2M medium adequate Scenario 2 represents transmission capacity peak Based on the analysis 58GHz short haul MWR not in demand Transmission capacity/bts [Mbps] Traffic scenario 1.1 Traffic scenario 1.2 Traffic scenario Simultaneously served subs./bts at busy hour 6-sector 3-sector SRC ul + MHA 3-sector GSM/EDGE/WCDMA + MHA 3-sector ROC 2-sector 1+1 ROC 14 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen

15 15 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen Conclusions

16 NetDim results, general Selection of service mix has paramount effect on the required number of sites for given capacity, coverage, and QoS targets The site count can be minimised with diversity techniques, by adding carriers, and increasing transmit power In conservative loading scenario cost for capacity is high in WCDMA compared to GSM GPRS EDGE evolution path, because technological discontinuity to 3G demands higher investments regardless of the projected subscribers Optimal sectorisation for macro cellular environment is 3-sector site both from performance point of view and in terms of co-siting 16 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen

17 NetAct results, general With low additional investment into transmission capacity the capability to serve simultaneous subscribers increases considerably As data traffic share breaks to 40%, transmission capacities per base station as high as 12Mbps at busy hour Despite of reuse of legacy equipment and existing media, dedicated WCDMA transmission is needed from the beginning Higher capacities compared to max. of 1-2Mbps per GSM site Higher site density ATM transport 17 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen

18 Optimal configurations 20W per carrier, Antenna system: 33 /18dBi Low asymmetry speech oriented traffic with low penetration Low asymmetry speech oriented traffic with high penetration Medium asymmetry data oriented traffic with high penetration Config: TRS capacity: 7 2M TRS media: SDH radio, leased lines, fibre 3-sector 20W per carrier, Antenna system: 65 /18dBi Config: TRS capacity: 2 2M TRS media: PDH radio, leased lines 3-sector triple-mode 5W per carrier, Antenna system: 65 /18dBi, MHA Config: TRS capacity: 2 2M TRS media: PDH radio, leased lines 2-sector 20W per carrier, Antenna system: 120 /18dBi Config: 1+1 TRS capacity: 2 2M Config: 1+1 TRS capacity: 3 2M Config: 1+1 TRS capacity: 3 2M TRS media: PDH radio 20W per carrier, Antenna system: 65 /18dBi, SRC ul and MHA TRS media: PDH (SDH) radio, leased lines, fibre Config: TRS capacity: 2 2M Config: TRS capacity: 5 2M Config: TRS capacity: 7 2M 18 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen

19 19 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen Support slides

20 Impact of DL code orthogonality For a given maximum UL load, the greater orthogonality allows for higher DL load, i.e. more capacity DL Load [%] 100,0 80,0 60,0 40,0 DL Load, 40% Orthogonality DL Load, 50% Orthogonality DL Load, 60% Orthogonality 20,0 For a given maximum UL load, the greater orthogonality allows for higher tolerable path loss, meaning more coverage Pathloss 0, UL Load [%] NRT Data 144k UL Pathloss NRT Data 384k UL Pathloss DL Pathloss, 40% Orthogonality DL Pathloss, 45% Orthogonality DL Pathloss, 45% Orthogonality DL Pathloss, 55% Orthogonality DL Pathloss, 60% Orthogonality UL Load 20 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen

21 Hardware assembly in 1.1 GSM/EDGE/WCDMA 5W and ROC 20W are light configs in terms of WPAs, also small power consumption The general rules 1 WAM per 1 WTR 1 WAM per 3 WSPs are not necessarily true with low loading, so even fewer WAMs may be adequate X-pol antenna MHA WPA 50W WPA 30W WPA 8W Number of units/bts WPA 5W WTR WSP 32ch WAM IFU 3-sector SRC ul + MHA basic 3-sector + MHA GSM/EDGE co-site 5W + MHA GSM/EDGE co-site 8W + MHA 6-sector 20W 2*(1+1) ROC 20W 2*(1+1) ROC 40W 3*(1+1) ROC 20W 3*(1+1) ROC 40W 3-sector SRC ul 1-omni 5W 1+1 ROC 20W ROC 20W ROC 40W basic 3-sector 20W ROC 20W GSM/EDGE co-site 5W Required number of sites increases 21 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen

22 Hardware assembly in 1.2 Growing demand for capacity shows as increase in the number of WTRs, and thus also in CEs X-pol antenna MHA WPA 50W WPA 30W WPA 8W Number of units/bts WPA 5W WTR WSP 32ch WAM IFU 3-sector SRC ul + MHA basic 3-sector + MHA 6-sector 20W 3-sector SRC ul basic 3-sector 20W 2-omni 40W GSM/EDGE co-site 5W GSM/EDGE co-site 8W ROC 20W GSM/EDGE co-site 5W + MHA 2*(1+1) ROC 40W ROC 40W 3*(1+1) ROC 40W 1+1 ROC 20W 2*(1+1) ROC 20W ROC 20W 3*(1+1) ROC 20W Required number of sites increases 22 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen

23 Hardware assembly in 2 Although the difference in HW setup per BTS is in favour of e.g. ROCs, the difference in required number of sites is equally remarkable Figure shows the required changes in site configurations once asymmetric data oriented traffic with high penetration becomes reality X-pol antenna MHA WPA 50W WPA 30W WPA 8W Number of units/bts WPA 5W WTR WSP 32ch WAM IFU 3-sector SRC ul + MHA basic 3-sector + MHA 6-sector 20W 3-sector SRC ul basic 3-sector 20W 3-omni 40W GSM/EDGE co-site 8W GSM/EDGE co-site 5W ROC 20W GSM/EDGE co-site 5W + MHA ROC 40W 3*(1+1) ROC 40W 1+1 ROC 20W 2*(1+1) ROC 20W 2*(1+1) ROC 40W ROC 20W 3*(1+1) ROC 20W Required number of sites increases 23 NOKIA Config_dim_in_WCDMA_RNS.ppt / / Jarno Toivonen