Overview of Research Activities on Time and Frequency at the Communications Research Laboratory
Abstract
Communications Research Laboratory (CRL) is a national institute, which is responsible for the national frequency standards in Japan. For this mission CRL has been conducting many research and development projects in the field of time and frequency standards. To introduce these projects, we will present following topics: - Development of primary frequency standards, such as an optically pumped cesium-beam frequency standard and a fountain type cesium frequency standard, - Time keeping at CRL, - Millisecond pulsar timing observations for long-term stability of time, - Millisecond pulsar timing observations for long-term stability of time scale, - Construction of low frequency stations for the dissemination of the standard time and frequency, - Precise time transfer using two-way satellite time-transfer and GPS carrier-phase method, - Construction of the calibration system for traceability of the frequency standard in Japan, - basic research on the next generation global satellite navigation system, such as the spaceborne hydrogen maser, and the precise time transfer method between satellite and ground station, and - research on the relativistic effects in the time scales and 4-dimensional reference frames.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1999
- Accession Number
- ADA495395
Entities
People
- Ken'ichi Okamoto
- Michito Imae
- Mizuhiko Hosokawa
- Noriyuki Kurihara
- Takao Morikawa