A method and a system for L1/L2 phase and magnitude determination in
satellite navigation equipment is disclosed herein. The method generates
separate W code estimates for the L1 signal and the L2 signal, the
estimates being uncorrelated with the error in the inphase and the
quadrature components of the corresponding signals. The W code is
estimated using both the L1 signal as well as the L2 signal. The L1 and L2
baseband signals are obtained from the corresponding RF signals. The
baseband signals are added and then filtered using a non-causal FIR LPF.
This filter has the property that the output at a time instant is
uncorrelated with the input at that time instant. In the preferred
embodiment, a one-W-code-bit I&D filter is used instead of a FIR LPF. In
an alternate embodiment, a single W code estimate is obtained for both the
L1 and the L2 signal.
