Analysis for Cross Correlation in Multiplexing

Several multiplexing techniques may be used in next generation GNSS, including QPSK, Interplex, AltBOC, TD-AltBOC, Dual QPSK, POCET. Multiple signals on the same carrier could be multiplexed into a constant-envelope signal with these techniques. Increasing of signals would deteriorate the crossing correlation and its impact on receiving is analyzed. It is shown that cross correlation between signals in-phase has considerable influence; in contrast, the effect could be neglected to signals quadrature. Simulation and real data test is given in the end to support the conclusion, which could guide the selection of multiplex technique and spreading code of Compass.