Method and arrangement for minimizing the autocorrelation error in the demodulation of a spread-spectrum signal subject to multipath propagation

摘要

A method is disclosed relating to an arrangement for minimizing the autocorrelation error in the demodulation of a spread-spectrum signal subject to multipath propagation. The received signal is received from a transmitter via a plurality of propagation paths. A demodulator produces a local spread sequence, which is correlated with the received spread sequence in a first control loop on a first phase-angle pair which has a first early-late spacing 2 &Dgr;₁, and which is correlated with the received spread sequence in a second control loop on a second phase-angle pair which has a second early-late spacing 2 &Dgr;₂. The first and the second control loop emit a first point phase value T1 and a second point phase value T₂, respectively, when in the steady state, which phase values express the phase angles of the received spread sequence with respect to the local spread sequence on the first phase angle pair or on the second phase angle pair, respectively. The phase value (T0) (which is supplied to a demodulation correlator) of the local spread sequence with respect to the received spread sequence is calculated using the formula T₀=(&Dgr;₂ T₁−&Dgr;₁ T₂)/(&Dgr;₂−&Dgr;₁), where &Dgr;₂ is chosen to be less than &Dgr;₁.