Tag: frequency and timing reference

EndRun Launches Two GPS-Based Timing Units
EndRun Technologies has launched two GPS-based timing products.

Meridian II Precision TimeBase.

The Meridian II Precision TimeBase references GPS to provide ultra-accurate time (10 nanoseconds to UTC) and frequency. At the core of Meridian II is a new GPS receiver that EndRun optimized to deliver a variety of traditional- and network-based time and frequency signals.

“The second-generation Meridian II continues EndRun’s heritage of pushing the envelope by delivering an industry-best, UTC time accuracy of 10 nanoseconds.” said Ron Holm, marketing manager, EndRun Technologies. “Meridian II also introduces a security-hardened, high-bandwidth network interface to synchronize evolving, network-centric applications via the Network Time Protocol (NTP) and IEEE-1588 Precision Time Protocol (PTP). Frequency standard customers will be happy to know that the revolutionary ultra-low phase noise and short-term stability performance of the original Meridian continues to be provided.”

Tycho II Precision TimeBase.

Also new is the Tycho II Precision TimeBase time and frequency standard, which references GPS to provide exceptional time (25 nanoseconds to UTC) and frequency (<1×10-13 per day) accuracy in a security-hardened, network-centric platform.

At the core of Tycho II is a new EndRun GPS receiver that is optimized to take advantage of improved GPS system accuracy. Tycho II delivers a variety of traditional and network-based time and frequency signals and services via a modular, customer-configurable platform. Operational status is easily monitored via the network interface (HTTPS, SNMP, SSH). Intuitive charts are provided to assess current and historical performance of Tycho II, its GPS receiver and reference oscillator.

“The second-generation Tycho II provides our customers with a cost-effective, high-performance time and frequency standard without compromise to security and reliability,” said Dan Paine, sales and support manager, EndRun Technologies. “In addition, Tycho II uses the same network-centric core of our ultra-high performance Meridian II TimeBase. This enables operation as a high-bandwidth, Network Time Protocol (NTP) server and optional IEEE-1588 Precision Time Protocol (PTP) Grandmaster.”

Both the Meridian II and Tycho II have modular architecture that allows customers to configure them to meet specific application requirements.

The units support mission-critical operations in a wide range of government and commercial applications including telecommunications, satellite communications, digital video broadcast, simulcast radio, test range, test and measurement, calibration labs and power utilities.

Meridian II Features
- Time accuracy of 10 nanoseconds RMS to UTC(USNO)
- Frequency accuracy better than 1×10-13 per day
- Short-term stability option, ultra-low phase noise 5/10 MHz option (<-115/-110 dBc @ 1 Hz offset)
- Dual gigabit Ethernet ports support high-bandwidth NTP server (7500 packets/second)
- Security-hardened to meet the highest Information Assurance requirements
- IEEE-1588 Precision Time Protocol (PTP) Grandmaster option with 8 nanosecond precision
- Modularity enables custom configuration for up to 23 outputs
Tycho II Features
- Time accuracy of 25 nanoseconds RMS to UTC(USNO)
- Frequency accuracy better than 1×10-13 per day
- Short-term stability option (<6×10-13 at 1 second)
- Ultra-low phase noise 5/10 MHz output option (<-115/-110 dBc @ 1 Hz offset)
- Dual gigabit Ethernet ports support high-bandwidth NTP server (7500 packets/second)
- Security-hardened to meet the highest Information Assurance requirements
- Optional IEEE-1588 Precision Time Protocol (PTP) Grandmaster with 8 nanosecond precision
- Modularity enables custom configuration for up to 23 outputs
October 7, 2015
Jackson Labs Delivers Low Phase-Noise Frequency and Timing Reference

The DROR-II by Jackson Labs.

Jackson Labs Technologies, Inc., a designer and manufacturer of GPS, timing and frequency equipment, is offering the DROR-II, a 10-MHz/5-MHz/1-PPS GPS-Disciplined Atomic Frequency and Timing Reference (GPSDO).

The DROR-II is a ruggedized frequency and timing reference with a Cesium Vapor Atomic Oscillator followed by a precision SC-cut Crystal Double-Oven Oscillator and an actively vibration-compensated VCXO oscillator, with specific emphasis on ultra low phase noise performance under extreme vibration and acceleration such as could be encountered in aircraft, tracked vehicles, and wheeled vehicles.

The DROR-II unit is optimized for operation in high-vibration and high-acceleration environments that require ultra-low phase noise performance and high frequency stability under extreme conditions. The DROR-II combines the strengths of three different on-board oscillators to provide an overall performance that has not been achievable with legacy products, at a steady-state power consumption of less than 3.85W, the company said.

The DROR-II uses a GPS receiver to provide long-term phase and frequency accuracy of the built-in CSAC atomic oscillator which is followed by an SC-cut, Double Oven OCXO (DOCXO) for very high short-term stability and low phase noise, which is itself followed by a three-axis electronically vibration-compensated crystal oscillator for ultra-low-noise under high vibration. Using these four signal sources cascaded to each other allows unmatched Phase Noise and Short Term Stability (ADEV) while also providing long-term atomic holdover, very fast warmup, and long-term phase-lock to UTC. Short term stability of 1E-012 (1ppt), and phase noise floors of -162dBc/Hz are achieved. Frequency stability over 24 hours is better than 5E-013 (0.5ppt) typically when locked to GPS.

The DROR-II supplies three isolated 10-MHz Sine Wave outputs, two CMOS 1PPS, and one 5-MHz output that is phase-synchronized to UTC via the internal GPS receiver. DROR-II contains a 50-channel WAAS/EGNOS/MSAS-enabled GPS receiver that provides support for avionics systems through integrated three-axis gyro-accelerometers and a -160-dBm GPS tracking capability. DROR-II power requirements are less than 3.85W steady-state, and only a single supply of between 11.0V to 32V is required. Support for an external LCD display is standard.

The unit can be monitored and controlled by an RS-232 port or a USB port via industry standard SCPI-99 Commands (GPIB commands), and is capable of generating numerous NMEA-0183 output sentences for easy integration into existing infrastructure. The DROR-II can be ordered with various OCXO options and with different temperature ranges.

February 7, 2014
Reminder: Leap Second This Weekend

News courtesy of CANSPACE Listserv.

Likely none of us needs a reminder as the upcoming leap second has been all over the news outlets for the past few days. But just to provide the details again, read this article.

Presumably, all GPS receiver manufacturers have checked to make sure their receivers will handle the leap second properly. However, at least one late-model high-end receiver from a leading manufacturer is currently reporting incorrect advance leap second information in its data files.

The European Satellite Services Provider (ESSP), the EGNOS system operator and EGNOS safety-of-life service provider, announced in a service notice dated 22 May that there might be an interruption in service for a 72-hour period should the leap second not be managed correctly.

AGI, a company that develops commercial modeling and analysis software for the space, defense and intelligence communities, has warned: “The consequence of failing to accommodate this event is that orbit in-plane motion and corresponding Earth orientation will both become inaccurate by at least one second until the leap second is properly implemented. This will also affect estimating orbits using time sequences of observations spanning this leap second event. GEO satellites might be inaccurate to about 3 km and LEO satellites to about 8 km. How great the discrepancy will be depends on how long one waits to implement the leap second. The probable inaccuracies may be within the collision keep-out zones of many satellites, causing either false alarms or totally missed threat detections.”

And it has also been reported that some computer operating systemsmight hang due to improper handling of the leap second.

An article on the upcoming leap second for the popular press may be found here. And, in case you missed it, a recent Physics Today article on the leap second and its future can be found here.

June 29, 2012