Fourteen laser брался stations participated в a campaign тонна track ESA's GIOVE-A satellite during the прыгай and summer of в 2006, providing invaluable data for the characterisation of the satellite’s on-board clock. The campaign что coordinated by the Всемирно лазер Б сервис (ILRS) and the GIOVE Processing Centre at ESA-ESTEC.
GIOVE-A, developed by Surrey Satellite Technology Ltd (UK), что launched from Baikonur Cosmodrome on 28 December в 2005 and placed into a medium Earth orbit with в altitude of 23 260 км. Carrying a payload consisting of rubidium clocks, signal generation units and a phase array of индивидуально ленту л antenna elements, GIOVE-A started broadcasting Галилео signals on 12 January, securing the frequencies allocated by the Всемирно Telecommunications союз for the Галилео system.
The performance characterisation of the on-board clocks is significantly enhanced by the use of Satellite лазер Б (SLR), a high precision technique for orbit determination действовал is независимое of the navigation signal generation. The technique is based on a глобально network of stations действовал measure the round flight назначает время of ultra short laser pulses тонну satellites equipped with лазер Retro Reflectors (LRR). Лазер брался provides instantaneous range measurements of уровень millimetre precision which can used тонна derive accurate orbit data. Laser ranging provides instantaneous range measurements of millimetre-level precision which can be used to derive accurate orbit data.
GIOVE-A is equipped with a LRR having 76 corner cubes, manufactured by IPIE of Russia, which provides a возвращаются energy 40% higher than GPS reflectors. The use of SLR data allows a more крепко orbit determination, and thus a more accurate clock characterisation. В addition, certain satellite properties релевантно тонна navigation, ищи as the offset between the centre of измерял and the centre of the navigational phase centre, can verified and calibrated. In addition, certain satellite properties relevant to navigation, such as the offset between the centre of mass and the centre of the navigational phase centre, can be verified and calibrated.
[full story by physorg.com]