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

2. 5G Key Features
High throughput
Low latency
High mobility
High connection density

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

4. Mobile Networks Synchronization

5. 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

6. 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

7. 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

8. 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

9. 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

10. 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
+/ nsec
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

11. 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

12. 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
( km/h)
High Security

13. Time Error Limitations for 5G

14. 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 V ( )

15. 5G Intra-Band Non-Contiguous CA: +/-260ns
Non Contiguous Blocks
Single Frequency Band UE
20MHz MHz
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

16. 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

17. 5G Intra-Band Contiguous CA: +/-130ns
Contiguous Blocks
Single Frequency Band UE
20MHz MHz
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

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