Study of geometric characteristics of inter-satellite links between LEO layer and MEO layer in LEO/MEO satellite constellation;

Tentative plan of a micro-satellite constellation used for reconnaissance;

The Study on Architecture and Key Technologies of the Military Satellite Constellation Communication Network Based on NEMO;

Handoff data registration strategy in satellites constellations communication system;

In order to minimize the mobility management signaling cost, the general scheme is to reduce the location update interval and the use of paging beams in satellites constellations communication system.

Call drop will occur when no satellite can be visible,handoff is not real-time and the corresponding response is lost in satellites constellations communication system.

Application of real time comparison to measuring satellite magnitude and it s precision evaluating;

Using the relationship,the satellite magnitude was obtained by the CCD gray value under the same conditions as integral time,attenuation slice,and so on.

Among the GPS satellite ephemeris,IGS ultra-rapid ephemeris which have twenty-four hours prediction orbit can be obtained momently by GPS user besides GPS broadcasting ephemeris.

The satellite ephemeris calculated by orbit determination sub-system in GEO positioning system is more real-time,more accurate than the satellite orbit parameters calculated by satellite Measuring and Control Center.

In this paper,satellite ephemeris and GPS carrier-phase observations are used to calculate the velocity/acceleration of vehicle.