基于ORBCOMM卫星机会信号的定位技术

In order to get rid of the dependence on Global Navigation Satellite System (GNSS) and overcome the problem that it cannot work under the condition of intentional or unintentional interference, we can use Signals of Opportunity (SOP) to realize positioning. Low earth orbit satellite SOP have advantages of strong signal power, wide coverage and no need for additional infrastructure. This paper proposes to use Orbit Communication satellite (ORBCOMM) system to realize space-based SOP positioning. Through a further research on the communication system of ORBCOMM signals, Doppler measurement information is obtained by ORBCOMM frequency-doubling signals, and ORBCOMM signals of opportunity positioning method is realized by combining the satellite TLE data with orbit prediction model after establishing mathematical models of instantaneous Doppler positioning and geometric dilution of precision. The experimental results based on actual ORBCOMM signal show that the positioning accuracy can reach better than 140 m.The research of this paper is significant in theoretical research and practice application of positioning technology based on space-based SOP.