Mobile Synchronization Trends 4G to 4.5G to 5G Nir Tshobani – Focus Telecom

5G Key Features High throughput Low latency High mobility High connection density

3 ways to support 5G Key Features More Base stations. More Spectrum. Use the current spectrum more efficially.

Mobile Networks Synchronization

LTE – FDD Frequency Network SyncE services to the eNB SSU LTE Macro Mobile Network Low eNB density EPC (Evolved Packet Core) Cs PTP Grand Master PTP services to the eNB

LTE-A: +/-1.5usec Phase Synchronization Distributed PRTC Architecture Dense Mobile Network PRTC PRTC SSU Cs Timing Moved to Network Edge PRTC PRTC PRTC EPC

LTE-A: End to End PRTC Solution Holding Precise Time at the Edge APTS from the Core PRTC to the Edge PRTC PRTC PRTC PRTC Cs APTS flows PRTC SSU PRTC PRTC EPC

Massive Increase in radios Massive Increase in Phase at Edge 5G Radio Densification at Network Edge: Phase Synchronization Everywhere ePRTC in the Core Massive Increase in radios PRTC PRTC PRTC Massive Increase in Phase at Edge ePRTC Cs PRTC Cs Cs ePRTC PRTC ULTRA RELIABLE 5G CORE ePRTC Cs PRTC PRTC PRTC PRTC PRTC

Massive Dependency of Infrastructure on Phase and Time Remote Remote Secondary Remote Remote Remote Remote Primary Remote Secondary Remote Secondary Primary Primary Remote Core Infrastructure Remote Remote Remote Secondary Remote Primary Secondary Remote Primary Remote Primary Secondary Secondary Remote Remote Remote Remote Remote

Mobile Network Synchronization Trends Macro, cRAN, Hetnet, IoT LTE-A & 5G NR adding functions that impose tighter sync requirements Network will have multiple sync requirements at the edge from relatively lax (IoT, WiFi) to very stringent edge cRAN clusters WiFi Macro Network 16ppb +/- 1.5usec Phase/time +/-40-100nsec CPRI cRAN eCPRI cRAN +/-750nsec or better ePRTC Phase/time +/-30ns PRTC PRTC Phase/time +/-100ns Hetnet Small Cells +/-750nsec – +/-1.5usec PRC Frequency G.811 PRTC SSU Frequency syncE Phase/time +/-100ns IoT

3GPP Release -12 Mobile Macro Network Functions New LTE Macro investment focus on migrating 3G to 4G. Macro eNB will continue to have critical role in 5G network provide excellent wide area coverage, often over 10s of kilometers, serve multiple RF bands spanning 700MHz to 2.6GHz. provide backhaul for other base stations. Are often real estate sunk investment “anchor” points Rel-12: adds enhancements that improve macro cell capacity and performance while lowering TCO and will carry over to 5G Carrier Aggregation (DL and UL), Active Antenna System (AAS) MIMO spatial multiplexing These functions will require phase-enabled access

5G Functions Need Phase At the Network Edge 1000 x 4G Bandwidth Massive MIMO Interference Management eICIC, COMP Hetnet Densification- Indoor & outdoor small cell Much More Phase Synchronization At The Mobile Edge 5G Frame format, CRAN Front-Haul architecture High Speed Handoff (350-500 km/h) High Security

Time Error Limitations for 5G

5G Time Error Limits (Under Discussion) (In addition to LTE-A (+/-1 5G Time Error Limits (Under Discussion) (In addition to LTE-A (+/-1.5usec) ) In addition to Macro network existing LTE-A compatible spec: +/-1.5usec 5G Application Time Error Comments 911 and Location +/-500nsec Proposed by ATT, DT, BT Intra-band non-contiguous Carrier Aggregation ±260 ns For Hetnet as complement to macro cells Inter-band contiguous Carrier Aggregation For Hetnet – possible with WR or TC+PTPinOTN Intra-band contiguous carrier aggregation, ±130 ns Only proposed by CMCC – not considered viable by most opco engineers Massive MIMO with Tx diversity at multiple Carrier frequencies ±65 ns For CPRI CRAN inter RRH & local only 3GPP TS 36.104 V13.1.0 (6.5.3.1)

5G Intra-Band Non-Contiguous CA: +/-260ns Non Contiguous Blocks Single Frequency Band UE 20MHz + 10MHz 30MHz to the UE Blocks of MHz are joined together to give more bandwidth to the UE This requires very good phase control to avoid overlapping and interference between the blocks Sync Requirement: Macro FDD 50ppb Macro TDD +/-1.5usec LTE-A hetnet +/-1.5usec 5G hetnet +/-260ns

5G Inter-Band Contiguous CA: +/-260ns Frequency Band A D UE 20MHz Contiguous Blocks Frequency Band B D 30MHz to the UE 10MHz Blocks of MHz joined together to give more bandwidth to the UE Requires very good control of phase to avoid overlapping and interference between the blocks Sync Requirement: Macro FDD 50ppb Macro TDD +/-1.5usec LTE-A hetnet +/-1.5usec 5G hetnet +/-260ns

5G Intra-Band Contiguous CA: +/-130ns Contiguous Blocks Single Frequency Band UE 20MHz + 10MHz 30MHz to the UE Sync Requirement: Macro FDD 50ppb Macro TDD +/-1.5usec LTE-A hetnet +/-1.5usec 5G hetnet +/-130ns Blocks of MHz joined together to give more bandwidth to the UE

Summary 5G Key Features – Throughput, Latency, Mobility, Density. Mobile Networks Synchronization Time Error Limitations for 5G