摘要 |
<p>A GPS system for determining precise position. The GPS system (20) includes a ground based GPS reference system which receives with a reference receiver GPS signals (25) and makes carrier measurements. The GPS reference system generates and broadcasts an initialization signal (27) having a carrier component, and a data link signal (30) having data representing the phase measurements made by the reference receiver. The GPS system includes a GPS mobile system which receives, with a position receiver, the same GPS signals as were received by the reference receiver, and the data link and initialization signals broadcast by the reference system. In response to the phase measurements made by both the reference receiver and the position receiver during an initialization period, the position receiver generates initialization values representing resolution of the integer ambiguities of the received signals, which are used, after the initialization period, to generate precise position determinations.</p> |