Synchronization Methods in Fronthaul

In order to meet the extremely tight synchronisation requirements of the 5G fronthaul network, the ITU-T is defining a new set of “enhanced clocks”. These clocks have around an order of magnitude better performance than the clocks defined for the 3G and 4G networks.

The new ITU-T clocks under development include the Class B PRTC (G.8272), ePRTC (G.8272.1), ePRC (G.811.1), eEEC (G.8262.1) and the Class C and Class D T-BC (G.8273.2). New network limits are being defined for these clock types, for example, the enhanced frequency network k limit in G.8261, and the enhanced time and phase network limit in G.8271.1.

A schematic representation of the ITU-T clocks is shown in the following figure. The concept is to separate the time and frequency distribution into two independent planes, using enhanced SyncE to distribute the frequency, and PTP to distribute the time and phase. The planes can be independently managed and routed, allowing more freedom to the operator to handle failure conditions and re-routing.

Some other organisations are also looking at fronthaul synchronization. IEEE802.1CM is a project looking at the use of time sensitive network techniques in Ethernet. The idea is to re-use the ITU-T clock types, but add extra capabilities such as time-aware shaping (defined in IEEE802.1Qbv) and pre-emption (IEEE802.1Qbu). IEEE1914.1 is also looking at defining the performance of the transport network in order to meet the fronthaul requirements.

Tim Frost
Strategic Technology Manager, Calnex Solutions.

Recent Blogs

Related Blogs

banana skin

Will SD-WAN really be the savior?

Mar 13, 2019
The only way to prove it is to get validation on how it will perform against your needs…
1951 Read more
Four Boardroom Members

How to Optimise Your IT Network and Spend

Feb 06, 2019
Network emulation can be a key tool to overcome barriers in getting the most out of your…
3091 Read more

Responding to IT Network Issues

Jan 22, 2019
If simple remedial scripts are not enough to fix an IT network issue, a more…
4002 Read more

Archived Blogs

1127 More

Timing not Telecoms

Nov 08, 2016
735 More

5G Coming Soon

Aug 22, 2016
759 More

What is 1588 PTP?

Aug 04, 2016
905 More

5G on the Horizon

Aug 01, 2016
765 More
776 More

What is a PTP Clock?

Apr 09, 2016
916 More

What is Time Error?

Oct 21, 2015
757 More

LTE-A & VoLTE Rollout

Sep 22, 2015
741 More

LTE Picks Up Speed

Aug 22, 2015
721 More

What is the Time?

Aug 22, 2015
725 More

Mobile and Sync

Aug 22, 2015
705 More

What is SyncE?

Aug 22, 2015
1393 More
807 More

Microwave Update

Aug 22, 2015
803 More

Unravelling Standards

Aug 22, 2015
770 More

Partial Progress?

Aug 22, 2015
724 More

Interpreting ITU

Aug 22, 2015
709 More

Confusion Rules!

Aug 22, 2015
736 More

Basestations Need Sync

Aug 22, 2015
754 More

ITSF 2015 Edinburgh

Aug 22, 2015
710 More

India to Follow China?

Aug 07, 2015
728 More
HOW CAN CALNEX HELP YOU FURTHER?

Click your area of interest below for more tutorials and real-world case studies.