AllIP RAN interworking IP RAN supports Rel 99

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All-IP RAN interworking • IP RAN supports • • • Rel 99 Iu (for

All-IP RAN interworking • IP RAN supports • • • Rel 99 Iu (for WCDMA and GERAN ), Rel 97/99 A and Gb/IP, Rel 99 Iur for WCDMA Rel 99 Iur-g for GERAN Rel'5 Rel 97/99 terminals --> Full interoperation with installed networks CN interface Nokia All-IP RAN UTRAN Rel'99, Rel 4 RNAS CSGW CRMS RNC Iub © NOKIA FILENAMs. PPT/ DATE / NN BSC SMLC Rel 99 UTRAN Iur LMU IP BTS OMS 1 BSS any release CRMS RNGW SMLC Iur-g for GERAN Rel'5 only Abis

Optimized architecture/ products for these worlds ? Traffic growth scenario Bits/s BH / user

Optimized architecture/ products for these worlds ? Traffic growth scenario Bits/s BH / user MBytes / user / day ~60/20/20 % traffic reference: best effort packet/ CS-voice/ RT packet data) 'application' bits over Air interface 2 © NOKIA FILENAMs. PPT/ DATE / NN

Nokia distributed All-IP RAN architecture • Multiradio architecture, with multimode All-IP BTS • User

Nokia distributed All-IP RAN architecture • Multiradio architecture, with multimode All-IP BTS • User plane and Control plane separated to allow optimised handling • Dynamic association between BTS and Radio Access Servers • Radio interface performance critical functions located in the BTS, close to radio • Transport optimised by relocating functionalities Upgrades to Nokia Ultra. Site and Metro. Site EDGE / WCDMA Base Stations Radio NW Common Radio Access O&M Resource Server © NOKIA FILENAMs. PPT/ DATE / NN Nokia Flexi. Server Nokia CS Gateway Gb IP / ATM / MPLS transport Iu-ps Multimode All-IP Base Station GSM/EDGE/WCDMA 3 A and Iu-cs Nokia RN Gateway WLAN

Core Network Gateways Iu. PS Uplane RNGW: RAN Gateway RNGW RAN Gateway is the

Core Network Gateways Iu. PS Uplane RNGW: RAN Gateway RNGW RAN Gateway is the user plane gateway for IP traffic. • Micromobility anchor for Iu-PS Uplane • Firewall t. b. d. © NOKIA FILENAMs. PPT/ DATE / NN BSGW Iu-CS A BSSAP/RANAP relay RNAS RNGW Ctrl Iu-PS 4 Iu. PS Cplane Platform: Flexi. Server Platform: IP 740 Platform: IPA 2800 CSGW Ctrl CSGW: Circuit Switched Gateway RNAS: RAN Access Server BSSAP'/ RANAP' Ctrl UCF RNAS Radio Network Access Server is the control plane gateway for RAN-external signaling. • Micromobility anchor for Cplane (terminates the signaling bearer connections, and relays L 3 messages) • Paging Server • O&M of CN interface (reset, overload) • RNGW and CSGW control BSGW A/IP, Iu-CS/IP CSGW Circuit Switched Gateway is the user plane gateway for non IP traffic • ATM to IP interworking (Iu-CS and Iur, both Cplane and Uplane • PCM to IP Interworking (A, Uplane and Cplane) • Transcoding • Micromobility anchor for A and Iu-CS Uplane

Common Resource Management Server RAN Common Servers O&M Server Serving Mobile Location Centre Platform:

Common Resource Management Server RAN Common Servers O&M Server Serving Mobile Location Centre Platform: Flexi. Server CRMS Common Radio Resource Management Server performs RAN Wide Radio Resource Management (inter cell/layers/system) • Load sharing • Policy Management • Autotuning for load sharing between layer 5 © NOKIA FILENAMs. PPT/ DATE / NN OMS O&M Servers performs RAN O&M functions • Connection to OSS • Logical O&M • System Info Broadcast • Configuration Manag. • Performance Manag. • Fault Manag. • Autotuning features SMLC Serving Mobile Location Center performs UE Positioning Calculations • Support of multiple positioning methods • Support of positioning request through 2 G and 3 G core • LMU control and O&M

UE Control Function • Termination of the CN signalling • Radio signalling (RR, RRC)

UE Control Function • Termination of the CN signalling • Radio signalling (RR, RRC) • RAB Admission control • Handover control • Initialisation of dedicated resources in the network ULTRA upgrade BS O&M • Termination of logical O&M interface • Implementation specific O&M 6 © NOKIA FILENAMs. PPT/ DATE / NN RR O&M Base Station Gateway • Termination of CN interface user plane • PDCP, RLC, MAC-d • MDC (Soft Handoff) • Ciphering CN Cplane CN Uplane UCF OMS Cell Resource Server • GRR protocol • Radio Admission control • Channel allocation and resource reservation • Load Control All-IP BTS CRS BSGW External Iur: one UE may use UCF/BSGW in Serving BTS, and CRS/CGW(L 1) in drift BTS Cell Gateway • GERAN PCU • WCDMA PS for shared and HS data channel • Retransmission CGW (Iub / Abis) BTS L 1 LMU SMLC Location Measurement Unit Could be external to the IP BTS L 1: Same functionality of Rel'99 BTS and Node B

All-IP RAN products 7 © NOKIA FILENAMs. PPT/ DATE / NN

All-IP RAN products 7 © NOKIA FILENAMs. PPT/ DATE / NN

High level BTS integration Example configuration • 3 sectored 2+2+2 solution • 384 code

High level BTS integration Example configuration • 3 sectored 2+2+2 solution • 384 code channels • multi-mode upgradeable Expansion slots 8 © NOKIA FILENAMs. PPT/ DATE / NN

Comparision, RNC functionality in IP RAN • Assumptions based on Peritus y. 2008 •

Comparision, RNC functionality in IP RAN • Assumptions based on Peritus y. 2008 • PS traffic: 12174 Mbit/s • CS tarffic: 4870 Mbit/s • subscribers: 13, 6 M • -> 168 rack s RNCs ( or 676 racks BSS 11 BSC ) RNAS • -> 5 racks RNAS • -> 30 racks CSGW • -> 15 racks RNGW RNC RNC RNC RNC CSGW • = 50 racks with IP RAN One rack = 10 racks 9 © NOKIA FILENAMs. PPT/ DATE / NN

All-IP Indoor Supreme BTS High Capacity All-IP BTS • Supports 1 -9 sectored solutions

All-IP Indoor Supreme BTS High Capacity All-IP BTS • Supports 1 -9 sectored solutions • up to 36 WCDMA carriers per cabinet • up to 1152 code channels per cabinet • multi-mode capable with All-IP RAN rel. 2 • ideal for multi-operator RAN • full support for Nokia Smart Radio Concept • ideal for indoor installations • Co-siting with existing BTS sites • Dimensions H x W x D 1800 x 600 mm • Operating temperature range -40 … +50 C • Mains Supply -48 VDC or 230 VAC 10 © NOKIA FILENAMs. PPT/ DATE / NN

All-IP Outdoor Compact BTS High Capacity All-IP BTS • Supports 1 -9 sectored solutions

All-IP Outdoor Compact BTS High Capacity All-IP BTS • Supports 1 -9 sectored solutions • up to 36 WCDMA carriers per cabinet • up to 1152 code channels per cabinet • multi-mode capable with All-IP RAN rel. 2 • ideal for multi-operator RAN • full support for Nokia Smart Radio Concept • ideal for outdoor installations • Co-siting with existing BTS sites • minimized site requirements due to small size • unobtrusive in roof top installations due to low cabinet height • Dimensions H x W x D 1500 x 770 mm • Operating temperature range -40 … +50 C • Mains Supply -48 VDC or 230 VAC 11 © NOKIA FILENAMs. PPT/ DATE / NN

All-IP Upgrade to Ultrasite WCDMA BTS Base station (BTS) software upgrade for new functionality:

All-IP Upgrade to Ultrasite WCDMA BTS Base station (BTS) software upgrade for new functionality: • Iub over IP in R 4 network • All-IP RAN BTS in R 5 Transport upgrade: • new IP router unit (IRIS), • reuse of RAN 1/RAN 2 IFUs (IP over ATM), or • introduction of new IP IFUs (no ATM) 12 © NOKIA FILENAMs. PPT/ DATE / NN

All-IP RAN Server Configurations - Examples OMS+RNAS+CRMS+SMLC OMS+RNAS+CRMS OMS+SMLC OMS+CRMS ( ca. 3 Msubs

All-IP RAN Server Configurations - Examples OMS+RNAS+CRMS+SMLC OMS+RNAS+CRMS OMS+SMLC OMS+CRMS ( ca. 3 Msubs ) ( ca. 1. 5 M subs ) (ca. 1. 5 M subs) ( ca. 1 M subs ) HDD OMS RNAS SMLC CRMS • Flexible configuration of nodes to different server applications; max. 44 nodes per rack • Connectivity to 1000 IP-BTS, max. 6000 IP-RAN cells; Capacities/node estimates with current call-mix assumptions for 2008: RNAS 150 k subs, CRMS: 250 k subs, SMLC: 375 k subs 13 © NOKIA FILENAMs. PPT/ DATE / NN

All-IP RAN Servers - Server Blades HW Cabinet Chassis 2 x LAN switches &

All-IP RAN Servers - Server Blades HW Cabinet Chassis 2 x LAN switches & Fiber Channel hubs, System mgt functions Up to 12 CPU slots Fan tray, display panel IP Director CPU Disk Drive • 9/11/12 nodes per subrack, two CPUs per node => 88 CPUs per rack • duplicated IP director per rack (one IP address, or very few addresses, visible to external network) • Pair of disks per rack (exact location in the rack FFS) 14 © NOKIA FILENAMs. PPT/ DATE / NN

RNGW • IP 740 platform • 19" racking • User plane throughput 44 Mbps

RNGW • IP 740 platform • 19" racking • User plane throughput 44 Mbps per RNGW (200 byte packets), 150 k RABs (max. 2. 5 k Handovers/s) • max. 18 RNGWs per rack => 792 Mbps and 2. 7 M RABs per rack 15 © NOKIA FILENAMs. PPT/ DATE / NN

1 cabinet 10000 channels 16 © NOKIA FILENAMs. PPT/ DATE / NN TCU MXU

1 cabinet 10000 channels 16 © NOKIA FILENAMs. PPT/ DATE / NN TCU MXU x MXU MX 622 -B PD 20 MX 622 -B IPNIU x x TBUF ISU TBUF 7 TBUF x. TCU x. CDSP TCU A 2 SU CDSP AL 2 S TCU IPNIU TCU A 2 SU AL 2 S CDSP TCU A 2 SU TCU CDSP ISU MX 622 -B CCP 10 x PD 20 IPS 1/IPGE CDSP MXU MX 622 -B CDSP AL 2 S TCU TCU TCU CDSP TBUF 7 CDSP 6 A 2 SU 6 CM / 1 TSS 3 (OMU) HDS CCP 10 (NEMU) HDS (OMU ) MDS PD 20 MX 622 -B TBUF WDU / 1 OMU / 1 WDU / 1 FDU x MXU 0/ 1 SPMU / 1 CACU / 1 CCP 10 TBUF (OMU) HDS CCP 10 (NEMU) HDS MCPC 2 ESA 12 EHAT PD 20 MX 622 -B CCP 10 x 7 CCP 10 5 TSS 3 WDU / 0 OMU / 0 WDU / 0 NEMU (NEMU) EHU x MXU 0/ 0 SPMU / 0 CACU / 0 CM / 0 NIS 1/ 0 NIS 0/ 0 / x x x 6 AL 2 SU 3 4 NIS 1/ 0 ISU CCP 10 SFU /0 x 5 IPS 1/IPGE 2 NIS 0/ 0 / x x SF 10 x 3 4 CDSP 5 7 A 2 SU TCU CDSP 3 4 6 AL 2 SU TCU CDSP 2 TCU 1 CDSP SFU /1 x 2 5 A 2 SU TCU CDSP SF 10 x 3 4 TCU IWU TCU 1 2 CDSP TCU CDSP IWU TCU IW 16 P 1 CDSP 1 AL 2 SU TCU • 10 000 Iu-CS channels per rack TCU • 1800 * 600 mm (H*W*D) rack CDSP • IPA 2800 platform CDSP CSGW 8 9 10 11 12 13 14 15 16 17 18 19

Core Site Solution ( incl. All-IP RAN Servers ) Core Site (IP/MPLS) HSS MSC

Core Site Solution ( incl. All-IP RAN Servers ) Core Site (IP/MPLS) HSS MSC CPS Server SGSN RNC GGSN MGW RNGW Interconnects CSGW All-IP RAN Servers IP ATM LAN/WAN connectivity (IP/MPLS) 17 © NOKIA FILENAMs. PPT/ DATE / NN OSR GSR SDH/ DWDM

Simulation on All-IP RAN gains 18 © NOKIA FILENAMs. PPT/ DATE / NN

Simulation on All-IP RAN gains 18 © NOKIA FILENAMs. PPT/ DATE / NN

Radio Performance gains in All-IP RAN • Introduction / Background • User Plane packet

Radio Performance gains in All-IP RAN • Introduction / Background • User Plane packet channel Gains • Control Plane packet channel Gains for Packet Services • Combined results • Other Potential Gains • Summary 19 © NOKIA FILENAMs. PPT/ DATE / NN

Radio performance in All-IP RAN -Setting up a session for a transport protocol (e.

Radio performance in All-IP RAN -Setting up a session for a transport protocol (e. g. TCP) is quicker in IP RAN due to faster transport and smaller RLC RTT - User experiences smaller delay in setup phase. Router All-IP BTS RLC Mobile Transport Protocol RLC - Transport is based on fast IP routing in IP RAN. - 'Information highway' ends in RNC in UTRAN, but lasts till IP BTS in IP RAN. - Routing of a packet from CN to IP BTS takes only few ms. No Iub in IP RAN --> - Smaller RLC RTT - quicker RLC retransmissions - User experiences better bit rate for bursty traffic 20 © NOKIA FILENAMs. PPT/ DATE / NN

Rlc and transport protocol 21 © NOKIA FILENAMs. PPT/ DATE / NN

Rlc and transport protocol 21 © NOKIA FILENAMs. PPT/ DATE / NN

All-IP RAN Gains for Packet Services Details on the transmission of a data burst

All-IP RAN Gains for Packet Services Details on the transmission of a data burst UTRAN Iub Setup Scheduling, RF meas. and pwr calc. Minimum allocation time of channels Transmission on DSCH Channel Allocation User Plane Time. Gain IP RAN Scheduling, RF meas. and pwr calc. Start: Packet scheduler decides to use DSCH transmission Transmission on DSCH Rel. Timer Shorter Faster RLC allocation RTTtime gives offaster DCH/DSCH that transmission thefaster gives No Iuballocation interface setup time, gives of release higher userofavailability timer data. can beofand reduced. codes and increased setup the DSCH associated DCH capacity. 22 © NOKIA FILENAMs. PPT/ DATE / NN Iub Release Timer Gain Control Plane Gain Channel User Release Plane Timer Allocation Gain: Control Plane Gain: Time Gain: Release Timer time

User Plane Gains for Packet Services (I) • Assumptions: • • • - TCP/IP

User Plane Gains for Packet Services (I) • Assumptions: • • • - TCP/IP traffic, e. g. web browsing, single object per page: TCP algorithms (slow start with 1 Maximum Segment Size initial window, MSS = 1460 B, delayed TCP acknowledgement) - TCP session setup: 3 -way handshake (3 messages, last setup message contains HTTP request) - RLC RTT 140 ms for UTRAN and 70 ms for IP RAN - Block Error Rate over radio 10% - Constant user bitrate over the radio interface - CN RTT 65 ms (web server very close to RAN). No server processing time. • Experienced Bit Rate: user bits / total TX time, without DSCH/DCH allocation delay • Gain (%): how much better experienced bit rate IP RAN gives compared to UTRAN with Iub interface • Result evaluated for WCDMA case, similar results for GERAN 23 © NOKIA FILENAMs. PPT/ DATE / NN

User Plane Gains for Packet Services (II) • Gain depends, for example, on the

User Plane Gains for Packet Services (II) • Gain depends, for example, on the allocated user bit rate, RLC BLER and the page size. Page sizes • The smaller the page the more gain -> the gain in the beginning of downloading • The bigger the user bit rate the more gain -> the big bitpipe used more efficiently in All-IP RAN 24 © NOKIA FILENAMs. PPT/ DATE / NN

Control Plane Gains for Packet Services (I) • The Control Plane (ex: allocation and

Control Plane Gains for Packet Services (I) • The Control Plane (ex: allocation and release of radio channel, channel switch, etc) is more efficient in All-IP RAN than in UTRAN, mainly thanks to that there is no Iub interface. • The gain from the more efficient Control Plane is especially large for packet services, due to the frequent change of state. • Evaluation: Find the improvement in download time • for files of different sizes • for different user bit rates on the air interface • Assumption: Iub setup time=350 msec, other parameters like in previous example. 25 © NOKIA FILENAMs. PPT/ DATE / NN

Control Plane Gains for Packet Services (II) • Note that the above gains are

Control Plane Gains for Packet Services (II) • Note that the above gains are found within Control Plane alone • In general, the gain is between 10 and 30%. • Gain is highest for small files and high bit rates • For most common file sizes and user bit rates, the gain is about 20 - 25% 26 © NOKIA FILENAMs. PPT/ DATE / NN

Combined User Plane and Control Plane Gains • The combined User and Control plane

Combined User Plane and Control Plane Gains • The combined User and Control plane results for Gain expressed in in terms of delay gains: -> DELAY REDUCTION UP TO 40 % 27 © NOKIA FILENAMs. PPT/ DATE / NN

Other gains expected from optimization of RRM algorithm • Reasons: Measurements from UE and

Other gains expected from optimization of RRM algorithm • Reasons: Measurements from UE and from. Speed IP BTS are available Note that HSDPA (High Packet Access) isin the same node RRM algorithms aresame preferably located as close as possible to the radio going in the direction as All-IP RAN: Proprietary BTS measurement are available for new optimized RRM algorithms and capacity enhancing features (no need of 3 GPP Iub standardization) • HSDPA scheduling moved to Node B • Example: • However, solution more complex as scheduling • Imagine that an algorithm needina the new. RNC. measurement in the BTS. forenhanced other channels are kept • In IP RAN, we implement it without waiting for 3 GPP. • In UTRAN, this measurement needs to be standardised on the Iub interface, meaning All-IP RANourovercomes problem! that we need to merge proposal withthis the opinions from other companies. • • • 28 © NOKIA FILENAMs. PPT/ DATE / NN

Conclusions • Users experience better service in All-IP RAN for packet data, with delay

Conclusions • Users experience better service in All-IP RAN for packet data, with delay for the transmission of a packet reduced up to 40% • Reduced code allocation time. • Potential optimization of RRM algorithm without the burden of using the predefined Iub measurement 29 © NOKIA FILENAMs. PPT/ DATE / NN

Case; transport comparision 30 © NOKIA FILENAMs. PPT/ DATE / NN

Case; transport comparision 30 © NOKIA FILENAMs. PPT/ DATE / NN

Input parameters • IP Router Buffer Sizes: • Leaf BTS, 30 kbytes (leaf means

Input parameters • IP Router Buffer Sizes: • Leaf BTS, 30 kbytes (leaf means last BTS in the tree topology) • Other BTSs, 100 kbytes 31 © NOKIA FILENAMs. PPT/ DATE / NN

IP RAN DS • 40% SHO OH for RT traffic only • IPv 6

IP RAN DS • 40% SHO OH for RT traffic only • IPv 6 • transport UDP/IP compressed • MDC in first starpoint Rt_Core DS 27. 66 Mbps 30. 04 Mbps Rt_D 2 DS Rt_A 1 1. 92 Mbps 2. 05 Mbps DS 2. 21 Mbps Rt_A DS Rt_A 2 DS DS 2. 05 Mbps Rt_D 1 Rt_D DS Rt_B 1 DS 21. 67 Mbps Rt_E 4 23. 93 Mbps 2. 05 Mbps DS DS Rt_B DS 2. 05 Mbps DS Rt_B 2 2. 05 Mbps DS 2. 05 Mbps Rt_E 1 8. 61 Mbps 2. 05 Mbps 4. 70 Mbps 2. 23 Mbps 9. 00 Mbps Rt_E 2 DS Rt_G Rt_B 3 DS 2. 05 Mbps Rt_C 2. 05 Mbps DS 2. 05 Mbps Rt_F Rt_C 3 2. 19 Mbps 2. 05 Mbps DS FILENAMs. PPT/ DATE / NN DS Rt_C 2 Rt_C 1 Rt_F 2 DS DS © NOKIA Rt_F 3 2. 04 Mbps 2. 22 Mbps Rt_B 5 32 DS DS Rt_E DS 2. 07 Mbps DS Rt_B 4 Rt_E 3 2. 05 Mbps Rt_G 1 DS Rt_F 1

RAN 1 • 40% SHO OH for RT and NRT traffic • No Stat

RAN 1 • 40% SHO OH for RT and NRT traffic • No Stat Mux gain 42, 6 Mbps • No centralised AAL 2 46, 86 Mbps 4, 26 Mbps 4, 26 Mbps 38, 34 Mbps 34, 08 Mbps 4, 26 Mbps 12, 78 Mbps 4, 26 Mbps 8, 52 Mbps 4, 26 Mbps © NOKIA FILENAMs. PPT/ DATE / NN 12, 78 Mbps 4, 26 Mbps 33 4, 26 Mbps

RAN 2 • 40% SHO OH for RT traffic only • Centralised AAL 2

RAN 2 • 40% SHO OH for RT traffic only • Centralised AAL 2 34. 54 Mbps 31. 4 Mbps 3, 14 Mbps 3, 14 Mbps 28. 26 Mbps 25, 12 Mbps 3, 14 Mbps 9, 42 Mbps 3, 14 Mbps 6, 28 Mbps 3, 14 Mbps © NOKIA FILENAMs. PPT/ DATE / NN 9, 42 Mbps 3, 14 Mbps 34 3, 14 Mbps

Comparison • RAN 2 with centralised AAL 2 compared with RAN 1 saves 15%

Comparison • RAN 2 with centralised AAL 2 compared with RAN 1 saves 15% - 30% in capacity • 15% is here refered to modest and 40% aggressive case of saving with Centralised AAL 2 of RAN 2 • Additional saving of RAN 2 compared with RAN 1 is the NRT traffic not having SHO OH Comparison against RAN 1 Comparison against RAN 2 ( 15 % ) 35 © NOKIA FILENAMs. PPT/ DATE / NN

Common Radio Resource Management 36 © NOKIA FILENAMs. PPT/ DATE / NN

Common Radio Resource Management 36 © NOKIA FILENAMs. PPT/ DATE / NN

Common Radio Resource Management (CRRM) Seamless integration of radio technologies to ensure optimum end

Common Radio Resource Management (CRRM) Seamless integration of radio technologies to ensure optimum end user performance and resource usage GSM/EDGE WCDMA multi-mode terminal GSM WCDMA GSM/EDGE WLAN WCDMA TDD Better capacity & quality level • Offer higher user bit rates and lower blocking • Enable load sharing and congestion control • Distribute interference • Enable multivendor RRM interoperability Easier operability • Simple interworking in multi-vendor / multi-system environment 37 © NOKIA FILENAMs. PPT/ DATE / NN Macro Micro Pico

CRRM Interfaces & Function • Nokia CRRM can connect to many different radio interface

CRRM Interfaces & Function • Nokia CRRM can connect to many different radio interface technologies • New standardisation is needed for an open multivendor CRRM interface CRRM server RNC IP-RAN WCDMA Other. . TDD, WLAN, . . GSM/EDGE x. RAN BSC • CRRM acts as an advisor to each system when making decisions • CRRM server is also the platform for other functions eg. • Setting idle mode parameters • Fast auto tuning 38 © NOKIA FILENAMs. PPT/ DATE / NN Cell Loads & Qo. S CRRM Set HO Parameters Handover Candidates Prioritized List CRRM

CRRM Simulation Results - Summary Qo. S class Capacity gain with 2 layers Conversation

CRRM Simulation Results - Summary Qo. S class Capacity gain with 2 layers Conversation Streaming No gain Interactive 40%-100% depending on the required delay Background Capacity gain with 4 layers 32 kbps 3% 144 kbps 10% 384 kbps 30% 70%-140% depending on the required delay Less gain than with interactive if no delay is guaranteed Reason for the CRRM gain Timers are needed to prevent ping-pong (and also useful handovers) without CRRM No load reason inter-system cell reselections assumed without CRRM • CRRM is most important • for interactive connections • for high bit rate (>32 kbps) conversational and streaming connections • when large number of layers and systems are integrated • Note: these gains are fairly ideal gains assuming no delays in signaling etc. With proper CRRM algorithms most of these gains can be obtained in practice 39 © NOKIA FILENAMs. PPT/ DATE / NN