Time Measurement and Analysis Service (TMAS)

Summary

The NIST Time Measurement and Analysis Service (TMAS) measures time with a combined standard uncertainty of 5 ns with respect to UTC(NIST), and frequency with an uncertainty of approximately
1 x 10^-14 after 1 day of averaging.

The service is based on the real-time, multi-channel GNSS common-view technique using a tri-band GNSS receiver at both locations (reference and device-under-test). Subscribers to the TMAS receive a time measurement system, which they install at their facility (all equipment remains the property of NIST). The system is calibrated at NIST prior to shipment and includes everything needed to continuously compare the customer’s time standard to the national standard at NIST.

The system accepts a 1 pulse per second (pps) timing output from the customer's time standard. The customer is required to supply an always-on Internet connection with a dedicated IP address, to install a GNSS antenna in an outdoor area, and to provide either a 5 or 10 MHz frequency source for use as a time base.

All measurement data is sent securely via HTTPS file transfer to a NIST server every 10 minutes, where it can be viewed immediately using any web browser. Therefore, customers can view their time and frequency offset and uncertainty with respect to the national standard at any given time, showing data up to the previous 10-minute upload. If any measurement system component fails, NIST replaces it as soon as possible using an overnight delivery service.

Description

Credit: NIST

The TMAS meets the requirements of any facility or organization that needs to maintain a high accuracy time standard. TMAS customers include calibration and metrology laboratories, telecommunication providers, instrumentation manufacturers, military installations, defense contractors, government research laboratories, and financial markets, stock exchanges and data centers. Each of these customers must continuously generate time signals and be able to state the uncertainty of those signals with respect to UTC(NIST) so that traceability to the International System (SI) of units can be established.

This service can be purchased with one or more of the following optional services:

76202C NIST Disciplined Clock (NISTDC), rubidium clock version

The NIST disciplined clock (NISTDC) - rubidium clock version - is for facilities without a time and frequency standard or who prefer having NIST supply and maintain a time standard.

The customer receives a rubidium clock (which remains NIST property) built-in to the measurement system. The rubidium clock is continuously disciplined, or adjusted, to agree with UTC(NIST) with a time uncertainty of about 5 nanoseconds and a frequency uncertainty of about 1 x 10^-14 at an averaging period of one day. The holdover characteristics for the rubidium oscillator will hold time accuracy better than a microsecond for several days, in case of a satellite and/or network outage.

The rubidium NISTDC provides at least seven (7) 1 pulse per second (pps) time outputs and three (3) 10 MHz frequency outputs.

Please note that the NISTDC is an option for the TMAS service (76201C) and only works with the TMAS service. Therefore, a subscription to 76201C is required before subscribing to the NISTDC.

76203C - NIST Disciplined Clock (NISTDC), cesium clock version

The NIST disciplined clock (NISTDC) - cesium clock version - is for customers who own a cesium clock, and who would like to have NIST continuously monitor and adjust their clock to agree with NIST time. A cesium clock has superb long-term holdover characteristics, better than a microsecond for many months.

The cesium is continuously disciplined, or adjusted, to agree with UTC(NIST) with a time uncertainty of about 5 nanoseconds and a frequency uncertainty of about 1 x 10^-14 at an averaging period of one day.

Please note that the NISTDC is an option for the TMAS service (76201C) and only works with the TMAS service. Therefore, a subscription to 76201C is required before subscribing to the NISTDC.

76204C NIST Disciplined Clock (NISTDC), quartz clock version

The NIST disciplined clock (NISTDC) - quartz clock version - is for facilities without a time and frequency standard or who prefer having NIST supply and maintain their standard, with good short-term stability, but less holdover characteristics than a rubidium oscillator.

The customer receives a quartz clock (which remains NIST property) built-in to the measurement system. The quartz clock is continuously disciplined, or adjusted, to agree with UTC(NIST) with a time uncertainty of about 5 nanoseconds and a frequency uncertainty of about 1 x 10^-14 at an averaging period of one day.

The quartz NISTDC provides at least seven (7) 1 pulse per second (pps) time outputs and three (3) 10 MHz frequency outputs and holdover capabilities are not needed. This option provides a traceable time and frequency output for the lowest cost.

Please note that the NISTDC is an option for the TMAS service (76201C) and only works with the TMAS service. Therefore, a subscription to 76201C is required before subscribing to the NISTDC.

76205C NIST Disciplined Clock (NISTDC), high-Q quartz clock version

The NIST disciplined clock (NISTDC) – high-Q clock version - is for facilities without a time and frequency standard or who prefer having NIST supply and maintain their standard, with excellent short-term stability, but less holdover characteristics than a rubidium oscillator.

The customer receives a high-Q quartz clock (which remains NIST property). The high-Q quartz clock is continuously disciplined, or adjusted, to agree with UTC(NIST) with a time uncertainty of about 5 nanoseconds and a frequency uncertainty of about 1 x 10^-14 at an averaging period of one day.

The quartz NISTDC provides at least seven (7) 1 pulse per second (pps) time outputs and three (3) 10 MHz frequency outputs and improved phase noise over the other options. This option trades some of the holdover capability of a rubidium oscillator for the best short-term stability.

Please note that the NISTDC is an option for the TMAS service (76201C) and only works with the TMAS service. Therefore, a subscription to 76201C is required before subscribing to the NISTDC.

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Upon choosing between the 76202C, 76203C, 76204C or 76205C services, you may optionally also select one or both services.

76206C - Time Code Output Service

The Time Code Output service is available for customers who have already subscribed to the TMAS (76201C) and the NIST disciplined clock service (either 76202C - disciplined rubidium clock, 76203C - disciplined cesium clock, 76204 - disciplined quartz clock, or 76205 - disciplined high-Q quartz clock).

The NIST disciplined clock services provide multiple pulse per second (pps) outputs that are synchronized to UTC(NIST). The Time Code Output service will provide a time code that is referenced to and aligned with the 1 pps signals from the NISTDC.

This time code is provided in two industry standard formats, which can be used as a time reference for computers throughout the customers facility/organization. The formats are the Network Time Protocol (NTP) and the Precision Time Protocol (PTP). This service is particularly useful for financial market customers who are required to keep accurate time inside their datacenters or stock exchanges.

Please note that the Time Code Output service is an option for the TMAS (76201C) and NISTDC services (76202C, 76203C, 76204C or 76205C) and only works if you also subscribe to the TMAS and NISTDC.

76207C - Time Code Monitoring Service

The Time Code Monitoring service is available for customers who already subscribe to the TMAS (76201C) and the NIST disciplined clock service (either 76202C - disciplined rubidium clock, 76203C - disciplined cesium clock, 76204 - disciplined quartz clock, or 76205 - disciplined high-Q quartz clock).

This service verifies and compares time codes transmitted by as many as 24 external servers by comparing them to a 1 pulse per second (pps) signal that is synchronized to UTC(NIST). The monitored time codes must be in the Network Time Protocol (NTP) format. Each of the 24 servers is monitored every 10 seconds, and 10-minute averages are available to graph.

The resolution of the Time Code Monitoring Service is 0.1 microseconds (100 nanoseconds) and the uncertainty is limited to one half of the round-trip network delay between the TMAS system and the time server under test.

This service is particularly useful for financial market customers who are required to keep accurate time inside their data centers or stock exchanges, etc. and who need to continuously verify that the time being transmitted by their servers is within specification.

Please note that the Time Code Monitoring service is an option for the TMAS (76201C) and NISTDC services (76202C, 76203C, 76204C or 76205C) and only works if you also subscribe to the TMAS and NISTDC.

76208C - Frequency Measurement and Analysis Service (FMAS)

The Frequency Measurement and Analysis Service (FMAS) add-on to TMAS, which adds eight frequency inputs between 1 Hz and 120 MHz. Two inputs can be configured as high-frequency inputs up to 3 GHz. All measurements are made automatically and are traceable to the International System (SI) of units through UTC(NIST) with a frequency uncertainty of about 1 x 10^-14 at an averaging period of one day. Measurement results from each channel can be graphed individually.

Please note that the FMAS is an option for the TMAS service (76201C) and only works with the TMAS service. Therefore, a subscription to 76201C is required before subscribing to the FMAS.

76209C – TMAS Backup Hardware

The TMAS Backup Hardware option is available for customers subscribing to the TMAS service with any options. A calibrated unit with all the same options is shipped to the customer as a spare, which can be kept in storage or near the operating TMAS. It is meant to be an immediately swappable backup in case of a failure of the TMAS, to operate until the TMAS is repaired.

Please note that the FMAS is an option for the TMAS service (76201C) and only works with the TMAS service. Therefore, a subscription to 76201C is required before subscribing to the FMAS.

NIST TMAS Specifications

Measurement Uncertainty (frequency)	1 x 10-14 (24 hour averaging time, k = 2)
Measurement Uncertainty (time)	<5 nanoseconds (k = 2)
Reporting	All results are made available in near real time (maximum 10-minute delay), viewable with any web browser. Monthly calibration reports are mailed or emailed by NIST.

NIST TMAS Pricing

To request a formal quotation, please call or email the contact listed on the right side of the page. Please feel free to email or call if you have questions or need additional information.

Description	Service ID number	Description	Monthly Cost
Subscription to basic TMAS service	76201C	Provides everything necessary for a customer to continuously compare their time standard to UTC(NIST). The monthly fee covers technical support, equipment replacement, data analysis, and all necessary supplies.	$1,300
Optional NISTDC services (Requires 76201C, only one can be selected)
NISTDC, Rubidium	76202C	Adds a NIST-supplied rubidium oscillator to the TMAS service. The rubidium is continuously disciplined to UTC(NIST) and has provides seven (7) 1 pps timing outputs and three (3) 10 MHz frequency outputs. In the event of failure, NIST covers the cost of oscillator replacement or repairs.	$400
NISTDC, Cesium	76203C	This service will keep a cesium standard owned by the customer continuously synchronized to within nanoseconds of the NIST time scale. However, please check with NIST to make sure that your model of cesium clock is supported, and please note that the customer is responsible for oscillator replacement or repairs in the event of failure.	$200
NISTDC, Quartz	76204C	Adds a NIST-supplied quartz oscillator to the TMAS service. The quartz is continuously disciplined to UTC(NIST) and has provides seven (7) 1 pps timing outputs and three (3) 10 MHz frequency outputs. In the event of failure, NIST covers the cost of oscillator replacement or repairs.	$200
NISTDC, Hi-Q Quartz	76205C	Adds a NIST-supplied Hi-Q quartz oscillator to the TMAS service. The quartz is continuously disciplined to UTC(NIST) and has provides seven (7) 1 pps timing outputs and three (3) 10 MHz frequency outputs. In the event of failure, NIST covers the cost of oscillator replacement or repairs.	$400
Optional Time Code Services (require 76101C and a NISTDC service, either 76102C or 76103C)
Time Code Output	76206C	Adds a synchronized time server to the TMAS service that outputs a time code in both the network time protocol (NTP) and precision time protocol (PTP) formats.	$400
Time Code Monitoring	76207C	Adds a measurement system to the TMAS that verifies and compares time codes transmitted by up to 24 external servers owned by the TMAS customer. It does so by checking them against the 1 pps signal from the NISTDC. The monitored time code will be in NTP format (if the server provides both PTP and NTP, the NTP code will be read and monitored).	$200
Optional Frequency Measurement and Analysis Service FMAS (requires 76101C)
FMAS	76208C	Adds eight (8) frequency measurement channels from 1 Hz to 3 GHz, which can each have a different frequency).	$400
In-place spare	76209C	A calibrated backup system can be kept in-site for an immediate swap, in the case of equipment failure and can be left in-place until the original measurement system is repaired.	$1,000

Ordering Information (request formal quotation before ordering). Subscribers issue a purchase order for the startup fee and at least 1 year of service. Invoices are sent quarterly, semiannually or annually. Delivery normally takes place within 4-6 weeks of receipt of an order.