Sea

Frequency Electronics has a long history of supporting the USNO and National Institute of Standards (NIST) time keeping mission and has 1000’s of space qualified rubidium frequency standards operating in space.  The FEI Digital Rubidium Atomic Frequency Standard (DRAFS) is one of the key master clocks for the future GPS launches.

Programs

FEI has two very important next generation atomic clock programs with the Office of Navy Research.  The Pulsed Optically Pumped Rubidium Atomic Frequency Standard (POPRAFS) as well as the Mercury Ion Clock in partnership with JPL promise future unmatched performance for Navy time keeping standards.

FEI builds mission critical solutions for the naval environment. FEI has in-house production capabilities of key-building-blocks of these systems like quartz fabrication to produce resonators and timing systems and vapor cell production using rubidium chloride to produce atomic clocks and other quantum sensing devices.  FEI designs, develops and manufactures space qualified solutions for programs like:

• • • • Navy SEWIP
      • Navy AOEW
      • ONR Next Generation Atomic Clock
      • USNO Master Clock
      • GPS

 

Capabilities

FEI Solutions integrate previously developed components and solutions from the list below into a deliverable subsystem that meets the customers requirements and which can include the below functions in single, dual and triple redundant configurations:

• • • • Atomic Frequency Standards
      • Oscillators
      • Synthesizers
      • Amplifiers/Distribution Modules
      • Reference Generators
      • DC-DC Converters
      • GPS Aided Time/Frequency Distribution and Synchronization Equipment
      • Integrated M-Code GPS Subsystems
      • Electronic Warfare Microwave Receivers, Frequency Converters and Frequency Synthesizers

Product Examples

For navy applications, all products are tailored made and developed specifically for customer requirements reusing and integrating previously developed components and subsystems.  The products on our website are just a fraction of the 1000’s of units FEI has delivered for navy applications.

FEI has two very important next generation atomic clock programs with the Office of Navy Research.  The Pulsed Optically Pumped Rubidium Atomic Frequency Standard (POPRAFS) as well as the Mercury Ion Clock in partnership with JPL promise future unmatched performance for Navy time keeping standards.

POPRAFS

Pulsed optically pumped rubidium vapor atomic clocks provide even better long-term stability with vapor cell clock simplicity. The typical rubidium lamp is replaced with a single laser light source and the filter cell is removed. All the remaining physics elements are proven legacy technology. The design is targeting a significant reduction in size, weight and power with a target size being a 2 slot 3U VPX.

A POPRAFS clock is expected to provide a 10 times improvement in stability:

• • • Flicker floor: σy(τ) = 3E-14/√τ
    • Stability: σy(τ) = 3E-12/√τ
    • Drift < 1E-14/day

 

Mercury Ion Clock

FEI is working with JPL to bring the JPL Mercury Ion clock technology from the laboratory to production.  This advanced ion clock technology enhances long term stability from electromagnetically trapped ions. It is a compact, environmentally robust design that is manufacturable. FEI is also developing a low ADEV quartz oscillator (σy (τ)∼ 3 × 10-13 at τ= 1s).

 

USNO Master Clock/GPS

The DoD common time reference is the U.S. Naval Observatory Master Clock.  It is generated at USNO in Washington, D.C. and at the Alternate Master Clock Facility at Schriever Space Force Base in Colorado.

U.S. Naval Observatory (USNO) which has provided timing for the Navy and the Department of Defense since 1830 and, in cooperation with other institutions, has also provided timing for the United States and the international community. Its Master Clock (MC) is the source of UTC (USNO), the USNO’s realization of Coordinated Universal Time (UTC), which has stayed within 5 ns RMS of UTC since 1999. The data used to generate UTC (USNO) are based upon 73 cesium and 21 hydrogen maser frequency standards in three buildings at two sites. The USNO disseminates time via voice, telephone modem, LORAN, Network Time Protocol (NTP), GPS, and Two-Way Satellite Time Transfer (TWSTT).

Today, USNO’s Precise Time Department is charged with maintaining the DoD reference for Precise Time and Time Interval (PTTI).  That reference is UTC(USNO).  This time-scale is determined by an ensemble of dozens of atomic frequency standards, popularly called “atomic clocks”, which are continuously scanned, selected, and averaged by computer to provide a day-to-day precision measured at the picosecond (10-12 seconds) level per day.

USNO monitors the Global Positioning System (GPS) constellation and provides system timing offsets to the U.S. Space Force 2nd Space Operations Squadron (2SOPS), timing data for individual GPS satellites, and time transfer services using GPS.

USN SEWIP

FEI-Elcom’s VMESG-2000 and VPXTR-6501 synthesizers are the perfect choice for Electronic Attack (EA), Electronic Countermeasures (ECM), Electronic Counter Counter Measures (ECCM) systems which require fast switching, phase coherent and phase continuous signal generation like the US Navy’s AN/ALQ-248 system. Elcom’s synthesizers are an important integral part of the NAVY SEWIP Block 3 Upgrade program.