Varying early-late spacing in a delay locked loop

摘要

A rake receiver tracks a component of a multipath information signal transmitted over a communication network. The rake receiver aligns and synchronized the component with a locally generated replica of the code sequence that was originally used to spread the information signal at the transmitter side. The rake receiver derives an early de-spread signal using an early shifted version of the replica of the code sequence. The replica is early shifted by a variable delay. The rake receiver also derives a late shifted de-spread signal using a late shifted version of the replica of the code sequence. The replica is late shifted by the same variable delay. The variable delay may be chosen arbitrarily or among a selection of predetermined values. The predetermined values may be selected so that the tracking process is optimized.