Microwave Clock Transmission Solutions

HUAWEI TECHNOLOGIES CO., LTD.

www.huawei.com

Huawei Confidential

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Transmission Network Marketing Support Department

Microwave Clock Transmission Solutions

HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 2

Document DescriptionDocument Name Microwave Clock Transmission Solutions

Objective Intended for the field product managers to learn and make clock transmission solutions, and to communicate with customers.

Intended Audience Sales personnel and marketing personnel

Content This document describes the meaning and principle of microwave clock synchronization, clock transmission capability, and common clock synchronization solutions.

Usage GuideVersion Information

Version Date Prepared by Approved by Issued by

V1.00 June 2010 Huang Zengsong, Zong Yong Wang Xiaozhong

Transmission Network Marketing

Support Department

V1.10 Nov 2010 Huang Zengsong Wang XiaozhongTransmission

Network Marketing Support

Department

Please delete this slide

before presentation!


Version Date Modification Prepared by Approved by Issued by

V1.2 Jun 2011Modify the roadmap of

1588V2Huabinshan Zhou xiao

Transmission Network

Marketing Support

Department


ContentsContents

33 Microwave Clock Transmission Microwave Clock Transmission SolutionsSolutions

11 Why Is the Clock Synchronization Why Is the Clock Synchronization NecessaryNecessary

22 Microwave Clock Transmission Microwave Clock Transmission ModesModes

44 FAQFAQ


Concepts of Clock SynchronizationConcepts of Clock Synchronization

What is a clock?A clock is a device that generates time signals. Clock signals involve the reference specifications such as frequency, period, jitter, and wander.

What is synchronization? Synchronization refers to that two signals appear or disappear in the same state at the same moment.

Clock synchronization refers to that all the devices on the network operate at the same rate.


Modes of Clock SynchronizationModes of Clock Synchronization

Frequency synchronization The signals remain a relative relationship in

frequency and phase. The corresponding valid instances appear at

the same average rate. As shown in Figure 1, clock B is six hours later

than clock A. Clock synchronization generally refers to

frequency synchronization.

Time synchronization The signals remain a consistent

relationship in frequency and phase. The phase of a clock is expressed in value,

that is, moment. As shown in Figure 2, clock B and clock A

remain the same in time at any moment.

Frequency synchronization

Clock A

Clock B

Clock A

Clock B

Figure 1

相位同步

Figure 2

Time synchronization


What Are the Impacts When the What Are the Impacts When the Clocks Are not Synchronized?Clocks Are not Synchronized?

Data:Characters in fax application are missed. The Internet is offline frequently.Mosaic images occur in the video services

Voice application:Calling failsconversation is not consecutive, and even crosstalk occurs. In the case of cross-boundary handover or dual-band handover, handoff occurs or the communication is unilateralism available.

Frequency Deviation Slips/per day

10E -11 0.007

10E -9 0.69

10E -7 69.1

10E -6 691.2Clocks not

synchronized

Impact of slip accumulation

Slip

Communication quality is

degraded ！


Requirements of Mobile Requirements of Mobile Communication for Clock Communication for Clock SynchronizationSynchronization

Mobile Communication

Technology

Requirement for Frequency

Synchronization

Requirement for Time

Synchronization

GSM 0.05 ppm NA

WCDMA 0.05 ppm NA

TD-SCDMA 0.05 ppm 3 us

CDMA2000 0.05 ppm 3 us

WiMax FDD 0.05 ppm NA

WiMax TDD 0.05 ppm To be determined

LTE 0.05 ppm 1.66 us (temporarily)

The requirements for clock synchronization are higher and higher!


ContentsContents

33 Microwave Clock Transmission SolutionMicrowave Clock Transmission Solution


22 Microwave Clock Transmission Microwave Clock Transmission ModeMode

44 FAQFAQ

Comparison of Application ScenariosComparison of Application Scenarios

Overview of Common Clock Transmission Overview of Common Clock Transmission ModesModesIntroduction to Microwave Introduction to Microwave ClocksClocks


Overview of Common Clock Transmission Overview of Common Clock Transmission ModesModes

Physical synchronization: a clock synchronization mode in which clock information is saved in a service stream.

Packet synchronization: a clock synchronization mode in which clock information is saved in a service packet.

Packet synchronization and time synchronization future-proof the clock synchronization technology.

Frequency synchronizationTime synchronization

Not supported by RTN equipment

Packetsynchronizatio

n 1588v

2

Physical synchronizatio

n SyncEth GPS

1588 ACR

CES

NTP

PDH/SDH

Supported by RTN equipment

Supported by wireless equipment

Microwave clockMicrowave clockOverviewOverview Application scenarioApplication scenario


PDHPDH Clock SynchronizationClock Synchronization

Transmit end: E1 signals are loaded into container C through bit adjustment, multiplexed into high-speed signals, and sent out at the system clock frequency f at the transmit end. (On the OptiX RTN equipment , the E1 retiming function needs to be enabled on the part as shown in the figure.)

Receive end: E1 signals are demultiplexed from container C by eliminating bit adjustment. The features of E1 signals remain the same. The OptiX RTN equipment extracts and traces E1 clocks to achieve clock synchronization , as shown on the dotted-line part.

Advantages: The principles and technologies are simple, facilitating the transparent transmission of clocks.

Disadvantages: Multiplexing and demultiplexing cause signal deterioration, which affects the transmission of high traffic.

Note: The traditional PDH network is a pseudo – synchronous network. It does not need to extract clocks or support the E1 retiming function.

High-speed signal

NE A NE B

fSystem clock unit

Service stream bearer clock

E1 Container C E1Container C

fSystem clock unit


High-speed signal


SDHSDH Clock SynchronizationClock Synchronization

Container Vc Container Vc

NE A NE B

fSystem clock unit


Service

Service

System clock unit f

Transmit end: Signals are loaded into container Vc, and sent out at the system clock frequency f at the transmit end. The STM-N bears the clock signal f.

Receive end: The clock signal f is recovered from the STM-N services, and sent to the system clock unit. The signals are considered as the system clock of the local NE and send out (as shown on NE A) to achieve the frequency synchronization between NE A and NE B.

Advantages: This technology is widely used and can meet the synchronization requirements of the SDH transmission network.

Disadvantages: The precision of the SDH clock synchronization only reach the millisecond level.



Synchronous EthernetSynchronous Ethernet

Transmit end: The Ethernet interface sends out Ethernet services at the system clock frequency f through the PHY chip. The service stream bearers the clock signal f.

Receive end: The clock signal f is recovered from the STM-N services, and sent to the system clock unit. The signals are considered as the system clock of the local NE and send out (as shown on NE A) to achieve the frequency synchronization between NE A and NE B.

Advantages: This technology is widely used and can meet the synchronization requirements of the Ethernet transmission network.

Disadvantages: The precision of the SDH clock synchronization technology is not high, and can only reach the millisecond level.

Note: The processing of synchronous Ethernet is similar to the processing of the SDH synchronization. The difference is that the service stream is the Ethernet service stream but not the STM-N service stream.

Ethernet interface

NE A NE B

f

System clock unit


Data service

Data service

System clock unit

f


Ethernet interface


IEEE 1588 V2 (Clock Architecture)IEEE 1588 V2 (Clock Architecture)

TCPrimary time

input

BC-11 2 3S M M

OC-1M

BC-21 2 3S M M

S

TC TCTC

BC: boundary clockOC: ordinary clockTC: transparently transmitted clock

SOC-2

OC-4M : master clockS: slave clock

OC model: only one port supports the transmission and extraction of IEEE 1588 V2 packets, and can either be the source or sink of the packets.

BC model: multiple ports support the IEEE 1588 V2 packets. To be specific, one port extracts and terminates the IEEE 1588 V2 packets, and the other ports generate and send out the new IEEE 1588 V2 packets. The BC contains the source and sink of the IEEE 1588 V2 packets.

TC model: processes the delay and transparently transmits clocks. The model does not extract and recover clocks.

Two NEs perform the relevant calculation based on the time stamps in the packets to achieve time synchronization.

SOC-3



IEEE 1588 V2IEEE 1588 V2 (Master and Slave Clock (Master and Slave Clock Synchronization)Synchronization)

Delay request packet

Synchronization packet

Delay response packet

t1 ， t2

t1 ， t2 ， t3

t1 ， t2 ， t3 ，t4

t1

t4

t2t3

Transmit end Receive end

△t1

△t2

The master clock transmits the synchronization packet at the moment t1, and the slave clock receives the packet at the moment t2 and obtains the time △t1.

The slave clock transmits the delay request packet at the moment t3, and the master clock receives the packet 2 at the moment t4 and obtains the time △t2.

Compute the trail delay and offset, and correct the time of the slave clock.Delay = (△t1 + △t2)/2 Offset = (△t1 - △t2)/2

Advantage: supports time synchronization, and is slightly associated with the PSN. The packets are transmitted independently, which is irrelevant to service transmission.

Disadvantage: All the equipment on the link needs to support the IEEE 1588 V2 protocol.



1588 ACR1588 ACR

Transmit end: transmits the synchronization packets 1, 2, and 3 at the frequency f with time stamps t1, t1', and t1'' respectively.

Receive end: receives the synchronization packets 1, 2, and 3, and records the arrival times t2, t2', and t2''. Due to the impact of different delays, △t1, △t2, and △t3 may be different. However, the received end adds different weights for the time stamps to achieve frequency synchronization.

Advantage: The clock synchronization is of good quality, and the protocol is standardized to support the interconnection of equipment from different vendors.

Disadvantage: only supports frequency synchronization but not time synchronization, and is easily affected by the PDV.

synchronization packet 1

t1 ， t2

t1 ’ ， t2 ’

t1’’ ， t2 ’’

t1

t1 ’’

t2

t2 ’

Transmit end Receive end

△t1

△t2t1 ’

t2 ’’



△t3

f fsynchronizatio

n packet N



GPSGPS

The global positioning system (GPS) is operated by the astronomical observatory of the U.S navy. As a precise satellite-based global navigation and location system, the GPS is composed of 24 communications satellites, three of which work as standby ones. The GPS can provide high precision clocks to the BTS, NodeB, or BITS. Advantage: the clock synchronization is of good quality, and time synchronization is

supported. Disadvantage: is costly and cannot be widely deployed.

GPS satellite

BITS

11111Costly

deployment

NodeB/BTS



Comparison Between Synchronization Comparison Between Synchronization TechnologiesTechnologiesSynchronization Technology

Frequency Synchronization

Time Synchronizati

on

Application Scenario

PDH √ X

1.The PDH network needs to be synchronized.2.The network provides PDH service interfaces only.3.The service needs to traverse the third-party PDH

and SDH lines.

SDH √ X 1.The SDH network needs to be synchronized.2.The network provides SDH service interfaces only.

Synchronous Ethernet √ X

1. PSN2. The network provides Ethernet service interfaces

only.

IEEE 1588 ACR √ X1.PSN2.The services need to transparently traverse the

third-party PSN.

IEEE 1588 V2 √ √ The network requires time synchronization.

GPS √ √ BITS and base stations that require high precision clocks from the GPS.



NodeB/BTSE1/FE/GE/external clock interface

The OptiX RTN equipment supports the transmission and reception of clocks at the slave clock interface, service interface, and air interface.

In actual networking, multiple clock bearer modes can be configured at the same time.

Air interface

External clock interface

Stm-1/E1/GE /FE service interface

Clock Bearer ModeClock Bearer ModeWith 3-PartyWith 3-PartyDesign principleDesign principle Typical scenarioTypical scenarioRTN networkRTN network

3

2

1 BITS

RTNRTN


ContentsContents


11 Why Is the Clock Synchronization NecessaryWhy Is the Clock Synchronization Necessary


44 FAQFAQ

Network Consisting of the OptiX RTN and Third-party Network Consisting of the OptiX RTN and Third-party EquipmentEquipment

Design PrinciplesDesign Principles

Typical ScenariosTypical Scenarios

Network Consisting of the OptiX RTNNetwork Consisting of the OptiX RTN Equipment onlyEquipment only


Clock Bearer Technology(Except Clock Bearer Technology(Except 900R3)900R3)

Type/Version 620R1/R2

620R3/R5 605R1 605R3/

R5 900R1 900R2

Service interfa

ce

SDH √ √ × × √ √

E1

Transparent

transmission

√ √ √ √ × √ Retiming √ √ × × √ √

ETH

Synchronous Ethernet × √ × √ √ √

1588V2 × × × × √ × 1588ACR × × × × √ ×

Air interface √ √ × √ √ √ External clock √ √ × × √ √ Two clock transmission modes are available for E1 services:

1. Clock transparent transmission: Transmitted E1 clocks are irrelevant to the equipment.

2. Retiming: Transmitted E1 clocks are equipment clocks.

With 3-PartyWith 3-PartyDesign principleDesign principle Typical scenarioTypical scenarioRTN networkRTN network


Clock Bearer Technology (RTN900R3)Clock Bearer Technology (RTN900R3)

Type/Version900R3C00(2011Q

1)900R3C02(2011Q2

)910 950/980 910 950/980

Service

interface

SDH √ √ √ √

E1

Transparent

transmission

√ √ √ √ Retiming √ √ √ √ CES ACR √ √ √ √

ETH

Synchronous

Ethernet√ √ √ √

1588V2 √ × √ Hardware ready1588ACR √ × √

Air interface √ √ √ √ External clock √ √ √ √

With 3rd-PartyWith 3rd-PartyDesign principleDesign principle Typical scenarioTypical scenarioRTN networkRTN network


Clock transmission capability: m1*k1 + m2*k2+……<=1Note: m1 and m2 are the hop counts of the link IF boards, and k1 and k2 are the transmission capability coefficients of the IF board in the corresponding modes.

Equipment Series IF Board Clock Type

Transport Capability

Coefficient kHop Count Supported Remarks

RTN 620

IF0 E1 0.1 10IF1 E1/STM-1 0.1 10 　IFX E1 0.1 10 　

IFH2Transparently transmitted E1 0.1 10 　System clock/Synchronous Ethernet/Retiming E1 0.05 20 　

RTN 605

1A/1B/2B Transparently transmitted E1 0.1 10 　1F/2F Transparently transmitted E1 0.1 10 　1D/2D/1E/2E Transparently transmitted E1/Synchronous

Ethernet 0.0625 16 　

RTN 950/910

IFE2 Transparently transmitted E1 0.1 10

IF1 System clock/Synchronous Ethernet/Retiming E1 0.05 20 　

IFU2Transparently transmitted E1 0.1 10 Supported by only the

OptiX RTN 900 V100R002System clock/Synchronous Ethernet/Retiming E1 0.05 20

IFX2Transparently transmitted E1 0.1 10 Supported by only the

OptiX RTN 900 V100R002System clock/Synchronous Ethernet/Retiming E1 0.05 20

Clock Transmission CapabilityClock Transmission CapabilityWith 3-PartyWith 3-PartyDesign principleDesign principle Typical scenarioTypical scenarioRTN networkRTN network


Clock InjectionClock Injection

Clock input point Clock signal trail

Chain network: The length of the radio link whose clock transmission capability is insufficient is L, and the clock transmission capability is N.1. 0 < L < N. The clock is injected at an upstream node.2. N =< L < 2N. The clock is injected at an intermediate node.

Star network: The clock is injected at a hub node.


Clock input Clock inputClock input

Clock injection at an upstream

node

Clock injection at an intermediate

node

Clock injection at a

hub node


Injecting the Clock from the BITS to the Injecting the Clock from the BITS to the OptiX RTN EquipmentOptiX RTN Equipment

A

BSC/RNC

E1

B

NodeB/BTS

E1/FE

Injecting the clock from the

BITS

The clock is transmitted through the external clock interface/E1, Ethernet, or SDH service interface and the air interface.

Note: When the clock transmission capability of the OptiX RTN equipment is insufficient, the clock needs to be injected from the BITS for clock compensation.

BITS

The clock is transmitted through the OptiX RTN

equipment

Injecting the clock into the base

station



Injecting the Clock from the Injecting the Clock from the Transmission Equipment to the OptiX Transmission Equipment to the OptiX RTN EquipmentRTN Equipment

A

BSC/RNC

E1

B

NodeB/BTS

E1/FE

Injecting the clock from the transmission

equipmentThe clock is transmitted through the external clock interface/E1, Ethernet, or

SDH service interface and the air interface.Note: When the clock transmission capability of the OptiX RTN equipment is

insufficient, the clock needs to be injected from the BITS equipment for clock compensation.

BITS

The clock is transmitted through the OptiX RTN

equipment

Injecting the clock into the base

station



Scheme 1 Clock Re-injectionScheme 1 Clock Re-injection

MUXThird party

MUX

B A

BSC/RNC

E1

C

FE

NodeB

NodeB/BTS

E1/FE

E1/STM-1/GEE1/STM-1/GE

After the clock traverses the leased line, the BITS re-injects the clock into the OptiX RTN equipment.

After the clock is re-injected, the microwave clock transmission solution is as on a network consisting of the OptiX RTN equipment only.

Re-injecting the clock from the

BITS


BITS

Network consisting of the OptiX RTN

equipment only



Scheme 2 Tracing the Clock from the Scheme 2 Tracing the Clock from the Third-Party EquipmentThird-Party Equipment

E1

C

FE

NodeB

NodeB/BTS

E1/FE

MUXThird party

MUX

B A

BSC/RNC

E1/STM-1/GEE1/STM-1/GE

Clock injection modes: injection through a service interface and injection through an external clock interface

Disadvantages: (1) The quality of the third-party clock is hard to be evaluated; (2) When jitters or degrades occur in the third-party clock the clock quality of the OptiX RTN equipment is affected, and the services may be faulty. The fault is hard to be located.

Tracing the clock from the BITS

equipment

Tracing the clock from the third-party

equipment

Not recommended




Scheme 3 Transparently Transmitting Scheme 3 Transparently Transmitting the Clock Through the Third-Party the Clock Through the Third-Party NetworkNetwork

MUXThird party

MUX

B A

BSC/RNC

E1

C

FE

NodeB

NodeB/BTS

E1/FE

E1/STM-1/GE

E1/STM-1/GE

Prerequisite: The third-party network provides the channel for transparently transmitting clocks (though a service channel, for example) so that network A and network C can be synchronized.

Supported services: E1, STM-1, and IP-based services on the third-party network. Clock synchronization mode: After the clock traverses the third-party network, only frequency synchronization

is supported. Computation of clock transmission capability: When the quality of the clock after traversing the third-party

equipment meets G.823 sync, the clock transmission capability needs to be multiplexed by 0.7; When the quality of the clock after traversing the third-party equipment meets G.823 Traffic, the clock transmission capability needs to be multiplexed by 0.1.

Tracing the clock form the

BITS

Transparently transmitting the clock

through the service channel

Extracting the clock of network A from the

service

Network consisting of the

OptiX RTN



1. E1 Leased Line1. E1 Leased Line

Network A: When E1 retiming is used, the network system clock is injected into the E1 service (recommended).

Network B: The E1 clock transparent transmission function needs to be supported (consult the third-party network supplier).

Remark: if the E1 retiming function is also enabled on network B, the E1 clock cannot be transparently transmitted.

Network C: The E1 clock is extracted.

MUXThird party

MUX

B A

BSC/RNC

E1 E1


Injecting the clock into the

E1 service

Transparently transmitting the E1

service

Extracting the clock from the

E1 service

E1

C

FE

NodeB

NodeB/BTS

E1/FE



2. 2. STM-1STM-1 Leased LineLeased Line

Third party

MUX

B

E1

C

Stm-1

E123

NodeB/BTS

E1/FE RTNRouter

BTS

1

Stm-1 Stm-1

A

RNC

Retiming E1 services, looping back the E1 services and cross-

connecting them to the VC-12s in the STM-1

Adding an OptiX RTN device for

time extraction

Transparently

transmitting STM-1 services

Extracting the clock

from the E1 service


OptiX RTN

E1

Network A: ① The E1 service is looped back. The E1 retiming function is enabled and the system clock is re-injected. The E1 clock quality meets the requirement (recommended).

Network B: Transparently transmits STM-1 services. Network C: ② Adds the IDU 620/910, extracts the E1 clock by broadcasting cross-connections, and

transparently transmits the STM-1 service. ③ Extracts the clock from the E1 service and receives STM-1 services.

MUX



3. Ethernet Leased Line3. Ethernet Leased Line

The third-party PSN meets the following conditions:1. The clock performance cannot be affected by PDV caused by transmission over PSN. The PDV cannot exceed

±10 ms. 2. The PDV values within one second must be the minimum values. These values completely or basically comply

with normal distribution, and meet the requirement of 6σ < 20 us. Disadvantages:1. The PDV of the third-party network is hard to be evaluated, which may introduce risks to the clock quality.2. Only the OptiX RTN 900 V100R001that is not a mainstream product support the IEEE 1588 ACR function.

MUXThird party

MUX

B A

BSC/RNC

ETH ETH


OptiX RTN

Using the 1588ACR function to inject the

clock into the Ethernet service

Transparently transmitting the Ethernet service

Extracting the clock from the Ethernet

service

Not recommended

E1

C

FE

NodeB

NodeB/BTS

E1/FE



Scenario 1 Transparently Transmitting Scenario 1 Transparently Transmitting STM-1 ServicesSTM-1 Services

Third party

MUX

B

E1

C

Stm-1

E123

E1/FE

NodeB/BTS

E1/FE

NodeB/BTS

OSN1500 OSN3500

Router

BTS

1

Stm-1 Stm-1

A

Scenario: Huawei's routers, OptiX OSN 3500, OptiX OSN 1500, OptiX RTN equipment, and third-party equipment construct the networks. The third-party network provides the STM-1 leased line.

Note: ① The E1 service is looped back. The E1 retiming function is enabled and the system clock is re-injected. The E1 clock quality meets the requirement (recommended). ② The added OptiX RTN NEs should be IDU 910/620 (the IDU 605 is not supported). The OptiX RTN NE trace the third-party clock.

RNC

Retiming E1 services, looping back the E1 services and cross-

connecting them to the VC-12s in the STM-1

Adding an OptiX RTN

device for time extraction

Transparently

transmitting the STM-1

service

Extracting the clock

from the E1 service



MUX


Scenario 2 Using the GPS Clock at the Base Scenario 2 Using the GPS Clock at the Base StationStation

Scenario: The OptiX RTN equipment and the third-party equipment construct networks, achieving clock synchronization between the RNC/BSC and the NodeB/BTS.

Note: The clock signal of the NodeB/BTS is obtained from the GPS. The OptiX RTN is not involved or need not be synchronized. ① After the clock traverses the third-party network or when the clock does not meet the requirement, the

clock mode is set to the free-run mode on the OptiX RTN equipment to provide the clock to the downstream NEs.

② Traces the clock that is in free-run mode on the OptiX RTN equipment.③ Not all the NodeB/BTS is capable of obtaining clocks from the GPS.

A

RNC/BSC

MUXThird party

MUX

BE1

C

NodeB/BTS

E1/FE

In free-run mode, providing the clock for the downstream OptiX RTN

equipment

BITS clock

Clock in free-run mode

BTS

123

Obtaining the GPS clock at the NodeB/BTS



Scenario 3 IP Services without ClocksScenario 3 IP Services without Clocks

A

BSC/RNC

FE

NodeB/BTS

FE

FE

NodeB/BTS

B

① Externally connected to the GPS

② Connected to the external clock

interface

③ Idle E1 clock

①The base station transmits the framed E1 signal.②The received E1 service is looped back on the cross-connect unit, and is retimed for clock injection. ③The E1 clock is transmitted to the base station.

BTS

Scenario: The NodeB/BTS transmits all IP services. The OptiX RTN 600 or NodeB/BTS does not support synchronous Ethernet.

Note: In the case of scheme 1, note that not all the NodeB/BTSs are capable of obtaining clocks from the GPS. For details, contact the headquarters of the wireless product line.In the case of schemes 2 and 3, only the IDU 620/950/910 support the clock transmission through the external clock interface or E1 retiming function.



Scenario 4 Using the IP Clock Scenario 4 Using the IP Clock EquipmentEquipment

MUXThird party

MUX

BC3FE

NodeBFE

NodeB

OSN3500 Router

NodeB

1

A

RNC

IP clock

FE

In free-run mode, providing the clock to the

downstream RTN NEs

2


BITS to the RNC

Transmitting the 1588ACR clock packet in the

services

Extracting the IEEE

1588 ACR clock from

the FE service

Scenario: The OptiX RTN equipment and the third-party equipment construct networks. The NodeB transmits all IP-based services.

Note: The IP clock equipment is a clock source device developed by Huawei. The IP clock equipment transmits IEEE 1588 ACR clock packets to the NodeB to achieve clock synchronization (the OptiX RTN equipment cannot extract the clock packet).

Note: ① The IP clock equipment injects the IEEE 1588 ACR clock packet into the routers. The clock packet is carried in a independence the FE service. ② The PDV needs to be considered in the transmission of the IEEE 1588 ACR clock packet.

IP clock equipment

generates the 1588ACR clock

packet



Scenario 5 Using the Same Clock on Scenario 5 Using the Same Clock on the With 3-Partysthe With 3-Partys

E1

C

FE

NodeB

NodeB/BTS

E1/FE

NEC

Third party

NEC

B A

BSC/RNC

E1/STM-1E1/STM-1

OSN

Scenario: The OptiX OSN equipment, OptiX RTN equipment, and NEC's equipment construct the networks.

Disadvantages: (1) The quality of the third-party clock is hard to be evaluated; (2) When jitters or degrades occur in the third-party clock the clock quality

of the OptiX RTN equipment is affected, and the services may be faulty. The fault is hard to be located.

Tracing the clock from the BSC/ RNC

Tracing the OptiX OSN equipment clock

Tracing the NEC equipment clock

2 1

Not recommended



ContentsContents




44 FAQFAQ


Restrictions on the Synchronous Ethernet Restrictions on the Synchronous Ethernet Feature Enabled on the OptiX RTN 600Feature Enabled on the OptiX RTN 600

Only the GE interface on the 605 1F/2F supports synchronous Ethernet.

Only the IFH2 board on IDU 620 supports synchronous Ethernet.Support the output and input.

The four Ethernet service interfaces on the 605 1E/2E supports synchronous Ethernet. The FEx2 interface supports the output.

The GEx2 interface supports the output and input.

The FEx3 interface does not support.The GE interface supports the output and

input.

HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential

Typical BITS of Huawei

Page 40

BITS （ Building Integrated Timing Supply), get clock signal from GPS or other clock source equipment , then provide the clock for other communication equipments. Huawei provide V3/V5/V6(T6020) BITS equipments , and recommend use Synlock V3/V6(T6020) in microwave solution.

Frequency synchronization100 frequency interfaces output Suit for big network

Frequency synchronization16 frequency interfaces output Suit for middle or small network

Frequency&phase synchronization （ 1588V2 ）8/14 interfaces frequency /phase outputSuit for small network

recommendatory

Synlock V6 （ T6020 ）

Synlock V3Synlock V5

recommendatory


Q: How does the third-party clock traverse a network consisting of the OptiX RTN equipment?

A: This is similar to the solution for the clock of the OptiX RTN equipment traversing the third-party network. Two factors need to be considered: (1) the bearer mode of the clock; (2) whether the clock meets the requirement of the third-party network after traversing a network consisting of the OptiX RTN equipment.

Q: Where can I obtain documents about Clock solutions except this slide? A: You can download the relevant documentation set from the 3ms website.

Document URL Link

White Paper on Clock Transmission Over Radio (Chinese) 3MS

White Paper on Clock Transmission Over Radio (English) 3MS

http://3ms.huawei.com/mm/docMaintain/mmMaintain.do?method=showMyCreatedMMInfo&f_id=OP200912180050

http://3ms.huawei.com/mm/docMaintain/mmMaintain.do?method=showMyCreatedMMInfo&f_id=OP201001270003

Thank youwww.huawei.com

Microwave Clock Transmission Solutions

Documents

system clock

e1 retiming

clock synchronization

clock transmission

clock bearer

system clock

transmitted

optix rtn