software computer services computer software gps research and development calibration time innovative design defence satellite navigation counters industrial design peripherals Receivers art materials intelligence metrology Hydrogen Frequency oscillator antarctica Research And Development Team atomic clock Product Realisation peripheral products industry standard products Circuit Simulation Seismology Rubidium Frequency meters Position Fixing Software Clock Active Hydrogen Maser Radar Imaging Missiles Radiocommunication Test Systems Telecom Network Synchronisation International Time Synchronisation National Timekeeping Frequency And Phase Measurement Calibration Of Caesium And Rubidium Determination Of Earth Rotation Frequency Calibration Earthquake Research