Built-in Rubidium clock
or OCXO (default option)

Up to 1024 PTP clients

Triple Power Redundancy
3h operation on batteries

Double GbE Port
Optical and Electrical interfaces

zPulsar GM52

zPulsar GM52 is a double port PTP Grandmaster clock conceived to supply synchronization to a large number of clients across the Ethernet/IP network. Once disciplined the internal clock, the unit delivers highly accurate Frequency, Phase and Time in time-stamped PTP packets to all its clients that can be connected through electrical and optical interfaces.

zPulsar GM52 has additional inputs/outputs signals for timing including T1, E1, 10MHz, SyncE and 1pps / ToD. The unit is carrier class, fault tolerant, can also operate on batteries and has an excellent performance in hold-over mode when the atomic Rubidium clock is configured.

Fig 1. zPulsar GM52



  • 19inch / ETSI/1U/240mm rack mountable
  • Triple Power Redundancy (AC+DC+Batteries)
  • Fanless operation

Time interfaces

  • SMA (x4): for GNSS(n), 1pps(in), 1pps(out)
  • BNC (x2): for T1(in), T1(out), E1(in), E1(out), 10MHz(in), 10MHz(out)
  • RJ45: for T1(in/out), E1(in/out), 10MHz(in/out)
  • SFP (x2): for PTP (out), SyncE (in/out)
  • 1000BASE-T (x2): for PTP (out), SyncE (in/out)
  • RJ48 (x2): for 1pps(in), ToD(in), 1pps(out), ToD(out)

Fig 2. zPulsar GM52 back pannel


  • Double Gigabit Ethernet Port
  • 2048 PTP clients at full rate (128 packet/s)
  • CLI management interface
  • Remote management through SSH protocol

Time / Clocks

Internal Clocks

  • OCXO (default) better than ±0.1 ppm
  • Rubidium better than ±5.0e-11 (GPS disciplined, warm- up: 600s)

Internal Rubidium clock

    Free―run (No GPS)

  • Freq. accuracy (7.5 minutes warm up): ±1e-9
  • Freq. accuracy on shipment (24 h. warm up): ±5.0e-11
  • Aging (1 day, 24 hours warm up): ±0.4e-11
  • Aging (1 year): ±1.5e-9
  • GPS locked

  • Time/Phase accuracy (24 h. locked): ±20 ns
  • Frequency Accuracy: (averaged over one week) ±1e-11

    Hold - over

  • Freq. accuracy: ±1.5e-11 / 24h
  • Time accuracy: ±100 ns / 2h, ±1.0μs / 24h

OCXO clock

    Free―run (No GPS)

  • Freq. accuracy (7.5 minutes warm up): ±1e-7
  • GPS locked

  • Time/Phase accuracy (24 h. locked): ±25ns
  • Frequency Accuracy: (averaged over one week) ±1e-11
  • Hold - over

  • Freq. accuracy: ±3.0e-10 / 2h
  • Time accuracy: ±2.0μs / 2h


Fig 3. zPulsar GM52 front pannel display


  • Built-in GNSS receiver
  • GPS/GLONASS/Galileo
  • Onmidirectional antenna (SMA)

Input Clock References

  • Rates: T1, E1, 1.544 MHz, 2.048 MHz, 10 MHz
  • 1 pps, ToD
  • SyncE

Output Clock

  • T1, E1, 10 MHz
  • 1 pps, ToD


LTE operators, Power utilities, Finance corporations, Manufacturing plants, Terrestrial and Aerial transport, all are migrating to PTP protocol to satisfy the synchronization demands they have of their mission critical applications. Timing distribution across the existing Ethernet/ IP back-haul is now a commodity to match the required accuracy and redundancy level of these new scenarios to manage real-time events over wide, cellular and metropolitan areas.

Fig 3. zPulsar PTP Applications


Financial services rely on powerful transport layer capable to provide high speed, availability, security and reliability. At the timing side, NTP and GNSS has been la widely used to synchronize nodes, transactions, and to log time-stamped events in a chronological sequence. Nevertheless today are in the migration pace to PTP that will improve the quality and functionalities of this service.

Air Navigation

Timing is a key resource to ensure the correct operation of the Air Navigation Systems. Legacy signal --such as IRIG B, NTP and TDM-- are still on use but are being progressively substituted by PTP time stamping to provide a unique, accurate and coherent synchronization signals based on atomic clocks disciplined by GNSS and distributed across the IP network to the whole territory

LTE-TDD turn-up

LTE deployments have stronger requirements at synchronization plane in order to reduce the size of the cells reusing more often available frequencies and, very important, wireless terminals have to share up/downstream channels to improve the efficiency by using phase information.

Power Utilities

Smart grid automation requires extremely precise time accuracy --and stability as well-- for tasks such as peak-hour billing, virtual power generators, or outage management. It is also necessary for the automatic protection of high voltage lines that are permanently supervised, when a substations detects an event, it is timestamped and transmitted to ensure correct operation.