Dimensioning, configuration and deployment of Radio Access Networks. part 1: General considerations Mobile Telephony Networks 1
The Evolution of Mobile Telephony 1st Generation 2nd 3rd 4th Analogue Voice Roaming Digital Voice Low-rate data European standard HSPA Multimedia Services broadcast Services HSPA Multimedia Services broadcast Services NMT, AMPS GSM, PDC IMT-2000 IMT-Advanced TACS IS-95, IS-136 1980 1990 2000 2010 Evolving Mobile Generation 1G was innovation I can actually make a phone call in my car! 2G was revolution New infrastructure, frequencies and mobile terminals No backward compatibility, no NMT GSM handovers 3G was evolution New radio interface, reuse part of 2G network 2G/3G handovers 4G will be innovation, revolution and evolution New radio access and multi frequency usage, multi access Enhanced mobility and control functionality 2
Evolution of cellular systems TDMA (IS 136) GSM GPRS IMT 2000 Capable EDGE New spectrum Existing spectrum Existing spectrum HSPA+ PDC WCDMA HSDPA HSPA MIMO cdmaone 1xRTT CDMA2000 1xEV DO LTE Existing spectrum New spectrum 2G 9.6kbps 2.5G 144kbps 3G 384kbps 3.5G 384k/14.4 Mbps 3.75G 5.8/14.4 Mbps 3.9 4G 50/150 Mbps Voice+sms Packet services Higher data rates Very high DL rates Improved latency Improved efficiency Very high UL rates Improved latency Improved efficiency Extremely high rates Improved latency Improved efficiency Improved architecture... High data rates in mobile communications Shannon s limit Spectrum efficiency Spectrum efficiency = Throughput BW log 2 (1 +SNIR) SNIR Power-limited region (cell edge) Low SNIR Throughput proportional to SNIR Low bandwidth utilization (spectrum efficiency) BW-limited region (close to the site) High SNIR Throughput proportional to log(snir) Throughput saturation due to very high SNIR (close to site) Large SNIR increase leads to small throughput increase High bandwidth utilization (spectrum efficiency) 3
Mobile Telephony Network PSTN MSC HLR 50-200 BS MSC BS BS BS GSM Voice and data architecture 4
UMTS Network Architecture UE Uu Node B I ub RNC I u-cs VLR B MSC GMSC PSTN PSTN I ur D HLR C Gr Ge SGSN GGSN Node B RNC Gn I u-ps Gi Internet The cost of a 3G Network Mobile Networks generally consist of a Radio Access Network (RAN), a Core Network (Core) and mobiles RAN RNC MSC/ VLR GMSC HLR SGSN GGSN Node B Core Claes Beckman 10 70 80% 20 30% 5
Users of a 3G Network The relative equipment volumes needed to build a network vary between vendors but can generally be estimated to: MSC/ VLR GMSC Node B RNC HLR SGSN GGSN 1E6 1E3 10 1 Mobiles Bas stations Network Control Core Net Claes Beckman 11 UMTS/GSM/GPRS architecture GSM CN NodeB RNC VLR MSC SA 1 Handover MS Connected NodeB NodeB RNC LA 1 VLR MSC SA 2 GMSC PSTN Location Updating SMS-C EIR HLR AUC No Update Idle NodeB RNC LA 2 SGSN GGSN Internet UMTS GSM NodeB BSC GPRS CN BTS Radio Network Core Network 6
Evolved Packet System (EPS) / Long Term Evolution (LTE) architecture E-UTRAN EPC enb MME S-GW P-GW Handover UE Connected enb enb MME S-GW HSS Internet Cell reselectio n Idle enb PS Core PSTN LTE UMTS enb RNC CS Core Other 3GPP (or 3GPP2 technology) UTRAN UMTS CN 1) 2) 1a) 1b) 2G/3G Basic procedures 1) Power on! 1a) read System Information => - neighbours to monitor - Location Area Identity (store -etc. LA1 1b) 1b) Location Updating 1c) Update location Download subscriber data PLMN A LA2 3) 4) 3) VLR 1 MSC 1 4b) 4c) 1c) HLR MS is Idle Compares: serving cell <->neighbours 2) Intra LA cell change no updating needed 3) Intra MSC /VLR LA change Location Updating (VLR) LA3 4a) VLR 2 MSC 2 5c) 5b) 4)Inter MSC /VLR cell change 4a) Loc. Upd. 4b) Update loc. Download sub. data 4c) Cancel location PLMN B LA1 5) 5a) 5) Power on! (Roaming MS) 5a) 5a) Loc. Upd. 5b) Update loc. VLR 1 Download sub. data MSC 1 5c) Cancel loc. 7
LA1 2G/3G basic procedures Call setup Signalling Traffic LA2 * A * * ** *** B BSC 1 BSC 2 VLR data: MS-LA2 VLR 1 MSC 1 HLR data: MS-VLR1 HLR GMSC PSTN/ISDN Incoming call Speech connection setup + 46 70799... C Get number to serving MSC/VLR Incoming call Speech conn. setup Page (*) Page MS in LA2 - - MT - - (**) Radio channel establishment MT: Paging response Prepare traffic channel Go to TCH MS C A B BSC 2 MSC1/VLR1 HLR GMSC BTS MO: Service Request Traffic (***) MO 2G/3G basic procedures Handover Signalling LA1 Traffic RNC 1 A VLR 1 MSC 1 GMSC PSTN/ISDN LA2 B RNC 2 C Traffic Measurement Report Handover algorithm detects: A is better! => Handover to A Access Prepare to receive MS Go to BS A! Traffic UE C A B RNC 2 MSC1/VLR1 NodeB 8
Network Roll out Network roll out involves a number of processes for planning of Radio Capacity Coverage Transmission GSM 900 initial roll out 4/12 Reuse pattern for control Channels 3/9 for Traffic Channels Required sensitivity > 9 db C/I 9
GSM 1800 adding voice capacity Co incident cell boundaries or Seperate networks UMTS (3G) adding data capacity 3G rel 99 both voice and data HSPA adds packet data up to 24Mbps Where needed 10
Coverage Map Capacity and Quality Improvments Building New sites (GSM, UMTS or LTE) Coverage Capacity Adding Frequencies (e.g. 1800) Swapping network elements New technology Adding carriers Network optimization Kpi based SON 11
Site Equipment Site Room Equipment 12
Tower/Antenna Equipment 13
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