Patent ID: 6108324
Filing Date: 2000-08-22
Classification: H04B

Abstract:
A multipath searcher for use in a code division multiple access (CDMA) wireless communication system conveying a mobile communication signal, the multipath searcher comprising:a searcher path having as inputs a set of in-phase (I) and quadrature (Q) components at a time offset, for estimating a first plurality of Walsh symbol energy values, and selecting a first set of top Walsh symbol indices from the first plurality of Walsh symbol energy values;a finger Walsh energy generator having as inputs the set of in-phase (I) and quadrature (Q) components, for estimating a second plurality of Walsh symbol energy values and selecting a second set of top Walsh symbol indices from the second plurality of Walsh symbol energy values;a search metric adjuster having as inputs, the first set of top Walsh symbol indices, the second set of top Walsh symbol indices, and the energy metric, for generating a signal representative of a likelihood that the time offset corresponds to a valid time offset of the mobile communication signal during a time period equivalent to N Walsh symbols, wherein the signal representative of the likelihood that the time offset corresponds to the valid time offset is based on a number of identical indices from the first set of top Walsh symbol indices and the second set of top Walsh symbol indices; anda look-up table for outputting an energy correction value based on the signal representative of the likelihood that the time offset corresponds to the valid time offset.