Patent ID: 8958458
Filing Date: 2015-02-17
Classification: H04B,H04L

Abstract:
1. A method of estimating a scrambling code used on an uplink of a CDMA 2000 system, a signal emitted by a terminal on said uplink being scrambled using the scrambling code, and then spectrally spread using a spreading code and shaped with a shaping filter, said scrambling code being generated by a generator comprising a shift register looped back on itself, said method comprising: sampling the signal received by a receiver at twice a chip frequency of the spreading code; filtering the signal thus sampled with a filter matched to the spreading code and to the shaping filter to obtain a series of samples at said chip frequency; applying differential processing on the samples at an output of the matched filter, said differential processing supplying differential values obtained as Hermitian product of samples from said series; decoding iteratively said differential values to obtain a content of values stored in the shift register of the generator of a first maximum length sequence (M-sequence) representing a sum of two offset versions of the scrambling code; and determining, using the content of values stored in the shift register of the generator of said first M-sequence, a content (a