Asian Surveying & Mapping
Breaking News
China Launches Earth Observation Satellite Gaofen-13 02 for Remote Sensing
China on Friday sent a new Earth observation satellite...
ISRO to conduct young scientist programme in Bengaluru
The Indian Space Research Organisation (ISRO) is organising a...
Egypt launches second remote-sensing satellite from China
The Egyptian Space Agency’s CEO, Sherif Sedky, announced the...
Israeli-developed DRONE DOME to secure Dubai from aerial attacks
Rafael Advanced Defense Systems Ltd. is supplying the system...
China launches 2nd Horus remote-sensing satellite for Egypt (video)
China has launched a second remote-sensing satellite for Egypt,...
China obstructs new subsea cable to Taiwan
Southeast Asia-Japan Cable 2 connecting Japan, Taiwan, Hong Kong,...
Scientific collaboration between China and US key to tackling climate change, experts say
Efforts to combat climate change bore the brunt of...
ISRO Receives India-US Jointly Built NISAR Earth Observation Satellite, Begins Preparations For Launch
US space agency NASA has handed over NISAR earth...
ISRO conducts parachute deployment tests on rail tracks for Gaganyaan Mission
Indian Space Research Organisation (ISRO) has conducted Rail Track...
OceanX helps Riyadh boost best up-and-comers in GEOINT
The Saudi Space Commission has given OceanX the difficult...

February 4th, 2011
Long-term Performance Analysis of Giove Clocks

Passive Hydrogen Maser (PHM) and Rubidium Atomic Frequency Standard (RAFS) are the two baseline on-board clock technologies for Galileo, the European Global Navigation Satellite System (GNSS), which are currently being validated on-board two experimental spacecrafts, GIOVE-A and GIOVE-B. These two spacecrafts are orbiting in a Galileo-representative orbit and transmit Galileo representative signals that are tracked and collected by a network of evenly distributed sensor stations (the Galileo Experimental Sensor Stations). The collected observables (pseudo-range and carrier phase) are being processed by the GIOVE Processing Centre, providing as one of its core product the estimation of the phase offset between the on-board clock and a reference clock, chosen to be an Active Hydrogen Maser connected to one of the sensor stations. Read More