The mission and organization of the Time and Frequency Division of the national Institute of Standards and Technology (NIST) are reviewed and a discussion is presented of recent activities. Among the major recent milestones have been the development of cold-atom frequency standards, including the construction of a new cesium-fountain frequency standard and the design of a standard for operation on the International Space Station. In addition, the use of GPS carrier phase for frequency transfer at the 1x10~(-15) level has been demonstrated, and the power radiated by WWVB has been increased to 50 kW. Other areas discussed include time scales, time transfer, optical frequency standards, and time and frequency dissemination services.
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