Title: Timing characteristics of telecom grandmaster clocks for frequency synchronization

On this page:

Summary

• Packet-Based Equipment Master Clock for Frequency (PEC-M-F)

• Takes PRC-quality input and generated PTP output

• Based on the G.812 Types I, II or III clocks (SSU clocks)

• Specifies frequency accuracy, noise generation, noise tolerance, holdover, testing methods

Status

• Current version: 1st. Edition, November 2016, plus Amendment 1, March 2018
• Download from: http://www.itu.int/ITU-T/recommendations/rec.aspx?rec=13106

Key Contents

• Three types of clocks: Type I (Europe), Types II and III (N. America)
• Performance characteristics based on the equivalent G.812 Types I, II or III:
  • Frequency accuracy (free-run)
  • Wander generation (but measured through a low-pass filter of 0.1Hz)
  • Wander tolerance
  • Wander transfer
  • Transient response and holdover
• Functional model: