| 摘要 |
<p>The location of a mobile terminal (12) in a given area is determined by including the mobile terminal (12) both in a satellite-based positioning system and in a cellular communications system (14). The mobile terminal (12) is thus adapted to receive satellite signals from the satellite-based system and to be covered by at least one cell of the cellular communications system (14). The mobile terminal (12) is configured for determining at least approximately its coordinates (x, y, z), including an altitude coordinate (z) in said area, based on both satellite signals received from the satellite-based system and information (52) related to the cellular communication system (14). An estimate of the altitude coordinate (z) is derived from the information related to the cellular communications system (14), whereby satisfactory location performance is ensured also when one or more satellites in the satellite-based system are not visible at the mobile terminal (12).</p> |
