To generate the main scrambling code of order N and the secondary scrambling code of order K within the set identified by the primary scrambling code of order N, a first m-sequence and a second m-sequence are generated using Fibonacci linear feedback shift registers. The first m-sequence and the second m-sequence are modulo-2 added to form the I branch of the primary scrambling code. A first T-bit masking word and a second T-bit masking word of rank 0 are generated that correspond to the polynomial time shifts, and the intermediate taps of the X and y registers respectively chosen by the masking words are modulo-2 added so as to generate a third sequence and a fourth sequence, which are modulo-2 added together to form the Q branch of the primary scrambling code. Starting from the least significant Kmax bits of the register X, of the K-th intermediate tap corresponding to the secondary scrambling code of order K within the set identified by the primary scrambling code of order N, a fifth sequence is generated, which, modulo-2 added to the second sequence, forms the I branch of the secondary scrambling code. By modulo-2 summing the intermediate taps of the register X masked by the first masking word of rank N, a sixth sequence is generated, which, modulo-2 added to the fourth sequence, forms the Q branch of the secondary scrambling code.

 
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