Technologie komunikacji bezprzewodowej GPRS and radio optimisation

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1 1 GRS and radio optimisation rezentacja jest współfinansowana przez Unię Europejską w ramach Europejskiego Funduszu Społecznego w projekcie pt. Innowacyjna dydaktyka bez ograniczeń - zintegrowany rozwój olitechniki Łódzkiej - zarządzanie Uczelnią, nowoczesna oferta edukacyjna i wzmacniania zdolności do zatrudniania osób niepełnosprawnych rezentacja dystrybuowana jest bezpłatnie olitechnika Łódzka, ul. Żeromskiego 116, Łódź, tel. (042) w ramach Europejskiego Funduszu Społecznego Agenda 2 acket transmission GRS/EDGE network and transmission channels overage optimisation problem Main performance indicators and optimization radio tasks

2 Bursty communication 3 Burstiness e l e m e t r y Notification oint of Sale File ransfer WWW Access Video 100 1K 10K 100K Bandwidth (bps) GRS Advantages 4 Efficient use of scarce radio resources A flexible service, with volume-based (or session duration-based) billing Fast set-up/access time Efficient transport of packets in the GSM network Simultaneous GSM and GRS, co-existence without disturbance onnectivity to other external packet data networks, using the I

3 GRS Evolution 5 bitrate UMS EDGE services up to 512 kbps GSM GRS services up to kbps GSM HSSD services up to 57.6 kbps GSM S data services up to 9.6 kbps 91/ /00 02 ime GRS Logical View 6 Signaling AU BS BS EIR FNR GGSN MS U RN S SGSN SMS Authentication enter Base Station ontroller Base ransceiver Station Equipment Identity Register Flexible Number Register Gateway GRS Support Node Mobile Switching enter acket ontrol Unit Radio Network ontroller Service ontrol oint Serving GRS Support Node Short Message Service AU H MS/ MS Server HLR HLR FNR FNR Gr Gs EIR EIR Gd Gf Ge SGSN SMS Gn S SGSN Gn Signaling and raffic Gn I Network Gi GGSN Gom Gom O&M BS A bis GSM BSS U BS Gb Gp Other LMN SGSN/ GGSN Gp

4 GRS Architecture 7 New nodes: SGSN and GGSN New interfaces: Gb (BS), Gs (MS), Gr (HLR) New radio channels acket switching mode Signalling plane for data transmission Different radio channel mapping SN SN LMN LMN MGW MGW R BS BS ISDN ISDN MSS MSS BS/R BS BS INERNE INERNE M EIR HSS GGSN SGSN URAN URAN SGSN Serving GRS Support Node Forwards incoming/outgoing I packets to MS rovides I packet routing to DN destination iphering and authentication Data session management Logical link management to MS Mobility management onnection to HLR, MS, BS, GGSN Output of billing data Geographical SGSN service area 8 INERNE INERNE GGSN SGSN BS/R BS

5 GGSN Gateway GRS Support Node 9 rovides interface toward external DN rovides access functionality with IS (e.g. DNS or RADIUS) Manages GRS session rovides communication setup toward external DN (e.g. MA address) Associates destination user with correct SGSN rovides output of billing data From outer works like packet router INERNE INERNE GGSN SGSN BS/R BS GRS Mobile erminal 10 lass A: It supports simultaneous circuit-switched and packet-switched traffic. lass B: It supports circuit-switched or packet-switched traffic, but does not maintain both kinds of traffic simultaneously. lass : It works either as a packet-switched or circuit-switched terminal.

6 Logical channels in GRS 11 acket Broadcast ontrol hannel BH acket ommon ontrol hannel H Logical hannels acket Dedicated ontrol hannel DH acket raffic hannel raffic DH H acket aging hannel (DL) RAH acket Random Access hannel (UL) AGH acket Access Grant hannel (DL) NH AH acket Associated ontrol hannel (UL/DL) acket Notification hannel (DL) H/D acket iming advance ontrol hannel (DL) acket Data raffic hannel H/U acket iming advance ontrol hannel (UL) GRS acket Data hannels 12 Dedicated DH All resources preconfigured and allocated Radio H Gb signalling link Abis link S Semidedicated DH Some resources preconfigured Dedicated radio H On demand Gb signalling link On demand (or dedicated) Abis link S On-demand DH All resources allocated on demand Radio H Gb signalling link Abis link S

7 Radio acket Segmentation 13 Application (server) down to SGSN SGSN H User data segment segment FH Info FS segment segment segment Application I SND LL BSS down to MS FH 114bits data BS 456bits Encoding and puncture Burst Burst Burst Burst 20 m sec RL/MA hysical EDGE 14 Enhanced Data rates for GSM Evolution GRS + EDGE = EGRS urrently: GMSK Modulation Q EDGE: 8SK Modulation (0,1,0) Q 1 I (0,0,0) (0,1,1) I 0 (0,0,1) (1,1,1) (1,0,1) (1,1,0) (1,0,0) 1 bit per symbol 3 bits per symbol

8 GRS oding schemes 15 oding Scheme Modulation method Max data bitrate over Um (kbps) S-1 GMSK 9.05 S-2 GMSK 13.4 S-3 GMSK 15.6 S-4 GMSK 21.4 EDGE Modulation and coding schemes 16 oding Scheme Modulation method Max data bitrate over Um (kbps) MS-1 MS-2 MS-3 MS-4 MS-5 MS-6 MS-7 MS-8 MS-9 GMSK GMSK GMSK GMSK 8-SK 8-SK 8-SK 8-SK 8-SK

9 GRS quality vs S 17 hroughput per timeslot S-4 S-3 S-2 S /I [db] GRS Link adaptation 18 here are three reasons for GRS Link Adaptation: Higher bit rates Low transfer delays Increased system capacity Four oding Schemes available on DL (S-1 to S-4) GRS Link Adaptation dynamically selects the most optimal coding scheme depending on the interference situation S-1 and S-2 is supported on UL and will be static

10 GRS Link adaptation parameters 19 hange to a higher coding scheme From o Required BLER S-1 S-2 < 4% S-2 S-3 < 6% S-3 S-4 < 2% A change to a lower coding scheme is performed if the BLER > 10% Up - and down switching points between coding schemes for EI Streaming BFs From o Required BLER S-1 S-2 < 0.1% S-2 S-1 > 1% EGRS Link quality control 20 Link Quality ontrol Link adaptation Incremental redundancy - Estimate the quality - hoose coding scheme - Re-segmentation is possible - Use very little coding at first - Send more coding if necessary - Receiver uses soft combining ossible to change mode during a BF!

11 GRS logical channels mapping 21 f 1 S0 S1... S7 Downlink: BH, Broadcast ontrol hannel f 2 f n BH Master DH DH Downlink: BH, acket Broadcast ontrol hannel AGH, acket Access Grant hannel H, acket aging hannel NH, acket Notification hannel AH, acket Associated ontrol hannel DH, acket Data raffic hannel H, acket A ontrol hannel DL Uplink: RAH, acket Random Access hannel AH, acket Associated ontrol hannel DH, acket Data raffic hannel H, acket A ontrol hannel UL Note: H printed in bold/italic Downlink/Uplink: DH, acket Data raffic hannel AH, acket Associated ontrol hannel H, acket A ontrol hannel DL/UL Master acket Data hannel 22 rimary SE BH SDH H H H H MDH H H H H H H DH DH DH Secondary SE

12 GRS flexible channel allocation (1) 23 SSALLO has the following values: B No preference (default) S first, S last S first, S no preference Hopping HGR S last, S first S last, S no preference S last, S last S no preference, S last S no preference, S first GRS flexible channel allocation (2) 24 B MS1 he average number of DL BFs per DH=1,0 and BFDLLIMI=1,8. No additional DHs are requested. B MS2 MS1 he average number of DL BFs per DH=2,0 and BFDLLIMI=1,8. Additional DHs are requested. B MS2 MS1 he system orders allocation of one additional DH since the BF limit is reached. B MS2 MS1 here is now increased capacity in the cell and a BF re-reservation is performed for MS2.

13 Multi Service Network 25 Messaging GRS/EGRS Network MMS WA Browsing otal download time Web browsing 26 lient Server F art Signalling

14 27 GRS erformance E2E Key erformance Indicators Accessibility KI:s GRS Attach failures, D ontext activation failures, GRS Service access failures Retainability KI:s F/WA/Web/SM/O3 transfer failures Integrity KI:s GRS Attach time, D ontext activation time, GRS R, GRS Service access time and transfer rates, GRS erformance Radio KI I hroughput 28 Measures the total amount of data divide by the total time taken to transmit it I Latency I latency measure the delay Gb - BSS - MS - BSS - Gb I ransfer Interrupts Determines how often the I transfer is interrupted

15 erformance levels analysis 29 I hroughput I ransfer Interrupts I Latency Interference apacity Mobility RL thp DL RL thp UL H congestion U congestion Multislot utilization DH sharing Inter RA or U RS Intra RA & U RS Sharing DHs Limited DHs No USF or FI HW fault reemption No DH MS capability R-MO Drive test. 30 GRS erformance erformance evaluation I Data Volume I hroughput I buffer discards I Latency Radio Link Quality raffic Load and sharing User Mobility

16 31 GRS erformance erformance evaluation hree test environments are defined in order to evaluate the GRS performance Ideal Environment ontrolled Environment Operational Environment 32 Wprowadzenie do przedmiotu rezentacja jest współfinansowana przez Unię Europejską w ramach Europejskiego Funduszu Społecznego w projekcie pt. Innowacyjna dydaktyka bez ograniczeń - zintegrowany rozwój olitechniki Łódzkiej - zarządzanie Uczelnią, nowoczesna oferta edukacyjna i wzmacniania zdolności do zatrudniania osób niepełnosprawnych rezentacja dystrybuowana jest bezpłatnie olitechnika Łódzka, ul. Żeromskiego 116, Łódź, tel. (042) w ramach Europejskiego Funduszu Społecznego