High Accuracy Timestamping

To meet the timing challenge of using Radio over Ethernet (RoE) in 5G Wireless infrastructure and to meet or exceed the Class C and D requirements, Synopsys (using formerly MorethanIP technology) provides a Time Prediction Unit that is designed to be used with Synopsys specifically optimized MAC and PCS Cores to reduce the Dynamic Timestamp Jitter.

The high accuracy Timestamping solution is supported with Synopsys (using formerly MoreThanIP technology) TSN MAC that implements Preemptive Frame transmission compliant to the 802.3br standard.

On Receive, the accurate timestamp is calculated from the FRC (Free Running Counter) provided by the system and the PCS and MAC timing and frame indications.

An accurate timestamp is calculated for each received frame that is returned to the MAC and provided on the Client interface with each frame.

On Transmit, the accurate timestamp is also calculated from the FRC (Free Running Counter) provided by the system with the PCS and MAC timing and frame indications.

In 2-Step mode, the transmit accurate Timestamp is provided to the Client application on the Timestamp return interface.

In 1-Step mode, the transmit accurate Timestamp is used to compute the Correction Field that is inserted in the outgoing Timing Frame.

With the Time Prediction Unit and optimized MAC and PCS Cores a better than 1ns precision (Dynamic Jitter) can, for example, be achieved in synchronous 25Geth with RS-FEC mode.

The Time Prediction Unit can be used for the Rates and Modes listed in the following table with Synopsys optimized MAC and PCS Cores.

Speed

Number of Lanes

FEC Options

FC-FEC

RS(528, 514)

RS(544m 514)

RS(272, 218)

10G

1

Y

 

 

 

25G

1

Y

Y

 

Y

40G

4

Y

 

 

 

50G

4

Y

Y

 

Y

2

 

Y

 

Y

1

 

 

Y

Y

100G

4

 

Y

Y

Y

2

 

 

Y

Y

1

 

 

Y

Y

200G

8

 

 

Y

Y

4

 

 

Y

Y

2

 

 

Y

Y

400G

16

 

 

Y

 

8

 

 

Y

 

4

 

 

Y

 

The Synopsys (using formerly MoreThanIP technology) high accuracy Timestamping solution can be implemented in Radio Units (RUs), Distributed Units (DUs) and Central Units (CUs) or any applications that require high Timestamping accuracy.

For more information contact designwareip@synopsys.com