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Calibrations Services in the Time and Frequency Division

NIST offers fee-based calibration services to customers who need the highest possible level of accuracy with the least amount of measurement uncertainty. Our services include remote calibrations of clocks and oscillators to UTC(NIST) via navigation satellite links, geostationary satellite links, and optical fibers. We also offer state-of the art services that perform delay calibrations of satellite timing receivers, measure the frequency stability of atomic oscillators, and that measure the phase modulation (PM) and amplitude modulation (AM) noise of frequencies as high as 110 GHz.




Time Measurement and Analysis Service (TMAS)


The TMAS works by making simultaneous common-view measurements at NIST and at the customer's facility with Global Positioning System (GPS) satellites. Time is measured with a combined standard uncertainty of about 10 nanoseconds, and frequency is measured with an uncertainty near 1 x 10-14 after 1 day of averaging.

SKU: 76101C

Frequency Measurement and Analysis Services (FMAS)

The FMAS makes it easy to measure and calibrate any quartz, rubidium, cesium, or hydrogen maser frequency standard. The service can measure any frequency from 1 Hz to 120 MHz in 1 Hz increments.

SKU: 76100C

Time Over satellite

This calibration is implemented as a link between the NIST time scale reference located at NIST Boulder and a customer’s facility, providing a time reference that is directly traceable to UTC(NIST) through a two-way link via geo-stationary satellite.


Time over Fiber

Provide a signal traceable to UTC(NIST) from NIST Gaithersburg/Boulder through a third-party optical fiber to a customer’s outside user facility. The initial goal will be to realize an accuracy of 1 microsecond in a remote location, with the eventual improvement to 100 ns or better.


SKU: 78100S


SKU: 78110S

Tests of RF PM/AM Noise Measurement Systems: On–Site Test

This is an on-site calibration service to measure the accuracy of phase modulation (PM) noise and amplitude modulation (AM) noise of customers’ measurement systems at 5 MHz, 10 MHz, 100 MHz, 1 GHz, 10 GHz, 20 GHz, and 40 GHz. To achieve this, a portable secondary PM and AM noise standard is sent to the customer. The accuracy of the measurement is determined by comparing the PM and AM noise measured by customer device with NIST calibrated noise levels (2-sigma uncertainty < ± 1 dB).


Special Time/Frequency Measurements: Oscillators and Other Components

This service offers calibration of PM and AM noise of oscillators, amplifiers, frequency multiplier/dividers, phase noise analyzers, and other components for frequencies ranging from 5 MHz to 110 GHz.


Characterization of Global Positioning System (GPS) Satellite Receivers

NIST has the capability to measure the accuracy of a one pulse per second (1 PPS) signal relative to UTC (NIST) at a level of at least ± 1 ns. The stability of the 1 PPS signal can be measured as either a time deviation at better than 0.1 n from 1 s to 104 s, or as an Allan deviation at better than 1 x 10-10/ τ level (τ in seconds). The frequency accuracy of 5 MHz and 10 MHz frequency outputs from the receiver can be determined to 5 x 10-15 for a one–day average, and the Allan deviation can be measured at the 1 x 10-13/ τ level.

SKU: 76120S

Characterization of 5 MHz frequency sources in the Time Domain

NIST provides services to characterize the short-term performance, in the time domain, of frequency sources. The output of the source under test is sampled at 1s intervals and compared with the 5-MHz UTC(NIST) signal. The frequency offset is measured with a relative standard uncertainty of 10-14, limited by the offset between UTC(NIST) and TAI, to determine the uncertainty of this calibration. The actual values transferable to the frequency source under test are often limited by the source's own stability and noise properties. Service requests will be evaluated on a case-by-case basis.

SKU: 77120C

Long-term, time domain characterization of frequency standards

SKU: 77110S

Characterization of Atomic Frequency Standards

SKU: 77110C

Short-term, time domain characterization of frequency standards


Created April 24, 2023, Updated September 22, 2023