Bit parallel algorithm for realtime acquisition and tracking of GPS signals
This invention discloses a bit parallel algorithm for real-time GPS signal acquisition and tracking. The technology of combining pre-generated one-dimensional cumulative table, 2D sine /cosine table and 3D pseudo-random code table storage, and searching the look-up table by the local carrier and the pseudo-random code, and mixing the local carrier and the pseudo-random code by XOR bit operation. The result should be input directly into the cumulative table and the relevance result is produced by cumulating the look-up table. Then, all the processing will achieve the relevance results on GPS signal acquisition and tracking. Usually, the GPS software correlator receive frequency commands for simulated carrier and code NCOs and uses these to reconstruct carrier and code replicas which it mixes with the input data stream. This patent uses the look-up table, bit operation and bit parallel correlation operation. So, the optimized technology will achieve the relevant increase of operation speed, and realize, in effect, to shorten the processing of the local carrier and the pseudo-random code, and greatly reduce the GPS signal demodulation time in the software GPS receiver platform.
11/SSC/414/ITF Inventor: Professor LIN Hui, Institute of Space and Earth Information Science
香港
