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Metrology

Time & frequency metrology

News and Updates

Blog Posts

Title card reads "A Scientific Christmas Tale" with the NIST logo in a wreath and flashing holiday lights.

A Scientific Christmas Tale

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An antique clock showing a few minutes before 12 is topped with a party hat, and colorful streamers hang in the background.

Auld Lang ‘Time’: One of the Country’s Timekeepers Makes Sure We Ring in The New Year at Just the Right Second

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A researcher wearing safety glasses reaches into a box of circuitry and other equipment, which emits a green glow.

Think You Know What a Second Is? It Will Likely Change in the Next Decade.

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Projects and Programs

The word "TIME" appears and grows larger among line drawings of various types of clocks.

Advancing Statistical Methods for Next-Generation Clock Networks

Ongoing
Atomic clocks are key to a wide array of technologies and scientific experiments, including tests of fundamental physics. Clocks operating at optical frequencies have now demonstrated fractional stability and reproducibility at 10 -18, two orders of magnitude beyond their microwave predecessors
Web interface to control and monitor the servo with interactive blocks

Field Programmable Gate Array (FPGA) Designs for Metrology

Ongoing
Until recently, the precision measurement of phase noise, spectral purity, and related quantities had been a challenging process, with only a handful of qualified experts in the world. However, Field Programmable Gate Array (FPGA) based measurement systems, similar to software defined radio (SDR)
5 MHz Graph of phase noise vs. offset frequency showing NIST synthesized signal, Wenzel OXCO, and BVA oscilloquartz.

Low-Phase Noise Frequency Synthesis

Ongoing
Frequency synthesis plays an essential role in virtually all present-day commercial, industrial, and military technologies. State-of-the-art low-noise frequency synthesis is a crucial technical asset to high-resolution imaging and radar, high-speed telecommunications, and efficient management of the
Image of AM/PM Noise Calibration Standard device made by NIST

Phase and Amplitude Noise Calibration Services

Ongoing
The primary responsibility of the Phase Noise Metrology Group is to develop and provide calibration services for industrial, military, and commercial organizations to support the core mission of NIST. The PM and AM noise measurements require traceability and certification of devices such as phase

Publications

Estimating How Big: The Metric Estimation Game

Author(s)
Elizabeth Benham, Kristen Dill, Dinelka Jagoda, Maryanne Amanze, Yoon Thwel
The metric system (International System of Units, SI) is easy to use and learn. The Metric System Estimation Game is a fun, hands-on activity that helps

Wavemeter calibration by frequency comb

Author(s)
Patrick Egan
Upgrades to the vacuum-wavelength calibration service at NIST are reported. The instrumentation centerpiece is an optical frequency comb tied to a GPS

Awards

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