LTE 架構、協定與效能 - speed.cis.nctu.edu.tw

1 1 LTE 300 1001 9-30-2011 4G LTE LTE (UE) (eNB) All-IP Control-plane User-plane Control-plane UE Control-plane Paging LTE All-IP Control-plane User-plane TA list DRX : LTE E-UTRAN EPC Paging DRX 1. LTE LTE (Long Term Evolution) 3 GPP[1] 4G 2008 3 GPP Release 8 2011 LTE 20 MHz 100 Mbps/ 50 Mbps LTE 2 500 3 GPP LTE 4G 2.

2 LTE LTE LTE E-UTRAN (Evolved Universal Terrestrial Radio Access Network) EPC (Evolved Packet Core) Control-plane User-plane Control-plane UE eNB MME User-plane UE eNB Serving Gateway Packet Data Network Gateway Evolved Universal Terrestrial Radio Access Network (E-UTRAN) E-UTRAN[2][3] LTE UE eNB (Evolved Node B) UE eNB UE eNB LTE-Uu LTE-Uu ( :3 GPP) eNBPHYUEPHYMACRLCMACMMERLCNASNASRRCRRCPD CPPDCPL ayer 1 Layer 3 Layer 2 3 NAS UE eNB LTE-Uu Layer 3: NAS (Non-Access Stratum) Bearers RRC (Radio Resource Control) RRC User-plane Control-plane LTE-Uu Layer 2: PDCP (Packet Data Convergence Protocol) RLC (Radio Link Control) ARQ HARQ MAC frame MAC (Medium Access Control) QoS Layer 1: PHY (Physical) OFDMA MIMO Evolved Packet Core (EPC) EPC EPC All-IP ( 2G 3G ) IP ( WLAN WiMAX ) :MME (Mobility Management Entity) S-GW (Serving Gateway) PDN-GW (Packet Data Network Gateway) MME Control-plane S-GW User-plane Routing/Forwarding Mobility Anchor( eNB ) 3 GPP Anchor LTE 3 GPP ( 2G/3G ) PDN-GW User-plane (Internet) SAE Anchor LTE 3 GPP ( WLAN WiMAX ) S1-MME ( :3 GPP) S1-U (.)

3 3 GPP) eNB S1 S1 Control-plane S1-MME ( MME ) User-plane S1-U ( S-GW ) S1-MME SCTP (Stream Control Transmission Protocol) TCP UDP S1-U SCTP L2 L1 IP L2 L1 IP SCTP S1-MME eNodeB MME S1-AP S1-AP UDP L2 L1 IP L2 L1 IP UDP S1-U eNodeB S-GW GTP GTP-U 4 GTP-U (GPRS Tunneling Protocol for the user plane) User-plane UE PDN-GW eNB S-GW IPv4, IPv6 PPP 3. UE UE [4] LTE_DETACHED LTE_ACTIVE LTE_IDLE LTE_DETACHED LTE_ACTIVE RRC RRC_CONNECTED UE UE UE LTE_IDLE RRC_IDLE IDLE UE Control-plane UE RRC RRC[5] RRC_IDLE RRC_CONNECTED LTE_IDLE LTE_ACTIVE IDLE UE UE RRC_CONNECTED SRB (Signaling Radio Bearer) DRB (Data Radio Bearer) RRC : RRC connection establishment: RRCC onnectionSetup RRCC onnectionRequest UE EUTRAN RRCC onnectionSetupComplete RRC connection establishment(.

4 3 GPP) UE 5 RRC connection establishment UE RRC_IDLE SRB0 establishment SRB0 SRB1 SRB1 establishment RRC RRC_IDLE RRC_CONNECTED C-RNTI (Cell Radio Network Temporary Identifier) UE RRC Initial security activation: SecurityModeComplete SecurityModeCommand UE EUTRAN establishment RRC Initial security activation PDCP UE eNB RRC connection reconfiguration: RRCC onnectionReconfigurationComplete RRCC onnectionReconfiguration UE EUTRAN RRC connection reconfiguration SRB DRB Initial security activation SRB2 NAS DRB reconfiguration RRC connection release: RRCC onnectionRelease UE EUTRAN UE IDLE RRC connection release RRC_CONNECTED RRC_IDLE RRC connection release( :3 GPP) RRC connection reconfiguration( :3 GPP) RRC Initial security activation( :3 GPP) 6 Attach Attach LTE_DETACHED LTE_IDLE LTE_ACTIVE Attach[6] UE eNB MME UE eNB RRC UE MME NAS Attach 3 GPP MME Control plane : 1.

5 2. UE eNB 3~6 RRC connection establishment NAS Attach Request MME TAI DRX 7. NAS Attach Accept Activate default EPS bearer context request 8~10 MME UE 7. eNB eNB UE MME UE Control-plane 7 11. 12. RRC Initial security activation UE 13~15 RRC connection reconfiguration SRB2 DRB NAS SRB2 DRB 15. MME 16. 17. NAS Attach Complete Activate default EPS bearer context accept Attach 4. Paging ( :3 GPP) MME eNB IDLE UE Paging UE UE Paging Paging Response IDLE ACTIVE LTE IP UE Paging Paging LTE IDLE ACTIVE 100ms TA (Tracking Area) UE eNB Cell TA Cell UE TA TAU (Tracking Area Update) TA LTE TA list TA list TA TA UE TA TA TA list TAU TA List UE TA Paging Paging UE UE TAU eNB TA TA list 8 LTE Always On IDLE LTE DRX (Discontinuous Reception)

6 [7] DRX DRX RF PDCCH (Physical Downlink Control Channel) , Inactivity-Timer DRX DRX On-Duration Opportunity for DRX On-Duration RF PDCCH Paging Opportunity for DRX RF Short/Long DRX cycle DRX Opportunity for DRX RRC_IDLE RRC_CONNECTED DRX RRC_CONNECTED RF UE eNB DRX eNB UE RF RF Paging Inactivity-Timer On-Duration Opportunity for DRX Short/Long DRX cycle 5. LTE LTE All-IP ; Control-plane User-plane TA list DRX Control-plane TA list 9 Paging DRX [1]3 GPP, Overview of 3 GPP Release 8 [2]3 GPP, TS , Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2(Release 10).

7 [3]3 GPP, TS , Evolved Universal Terrestrial Radio Access (E-UTRA); Medium Access Control (MAC) protocol specification(Release 10). [4]Motorola, Inc. Long Term Evolution (LTE): A Technical Overview, 2007. [5]3 GPP, TS , Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification (Release 10). [6]3 GPP, TS , General Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial Radio Access Network (E-UTRAN) access (Release 10). [7]Chandra S. Bontu and Ed Illidge, Nortel, DRX Mechanism for Power Saving in LTE. IEEE Communications Magazine, June 2009.