| 摘要 |
<p>Prediction methods for navigation message symbols of satellite systems, such as GPS and GLONASS, that use information repetition in navigation data messages are disclosed. An exemplary method comprises the first step of detecting the symbols of the first group within the frames of the information data stream signal (instruction set #1), and the second step of storing in a memory a sequence of the detected symbol values of the first group over at least M frames (instructions set #2). The method thereafter provides the sequence stored in the memory to the global positioning tracking process (instruction set #3). The exemplary method may subsequently monitor the data-stream signal to detect a change in the symbol values of the first group. This may be done by detecting the symbols of the first group within subsequently transmit frames, comparing their values with the sequence of previously detected symbol values stored in memory to find differences, and counting the number of differences encountered since the start of a groups</p> |
