| 摘要 |
<p>For pseudo-random noise (PN) code correlation, a GPS receiver employs sign and magnitude input weighting for each of the in-phase (I) and quadrature-phase (Q) samples of a received PN-code modulated carrier. A programmable R factor register (82) provides input A/D sample sign and magnitude weighting control by a multiplexer (84) of outside crossing samples for interference rejection of other RF signals interfering with the received PN-code modulated RF carrier. The R factor weighting determines whether the A/D samples (I out, Q out) are from a linear or adaptive A/D converter. In-phase reference (IREF) signals (CIX7:0) and quadrature-phase reference (QREF) signals (CQX7:0), produced by an internally generated PN-code reference system (48, 50, 52, 34, 36, Fig. 3), are provided to a plurality of I and Q multi-Y-tap correlator/integrators (88-102, 114-128 Fig. 9) for correlation with the I and Q samples. The apparatus correlates I and Q samples obtained from IF sampling or baseband sampling of the received PN-code modulated carrier. <IMAGE></p> |
