A Novel Creating Method of Ground Blockage Database by Civil GPS Receivers as Distributed Sensors

A new framework is proposed and demonstrated where satellite visible coverage seen from running vehicle is economically and effectively estimated with such low cost GPS satellite signal receivers like civil automobiles are equipped with. Our preliminary experiment indicated even economical L1 C/A 1.5 GHz civil GPS receivers can create enough precise database of ground feature blockage, if only two statistical parameters the author proposed are adequately set. Integrating the series of the author group´s efforts on this research field, it is expected feasible to develop an automatic database creation system in cooperation with the government and the civil vehicles with low cost civil GPS receivers. This blockage database enables us to make a real-time blockage prediction and feasible handover control in land vehicle satellite communication in future.