SELECTING ROOT INDICES IN MULTIPHASE CAZAC SEQUENCES Russian patent published in 2012 - IPC H04L27/26 

FIELD: information technology.

SUBSTANCE: disclosed devices and methods of creating a set of synchronisation channel sequences are resistant to systematic errors of time shifts and enable estimation of optimum frequency offset. A set of root indices is established for Zadoff-Chu sequences, which optimise the performance index or quality criteria in a first domain (e.g. time domain) or in an inverse domain (e.g. frequency domain). The optimum indices satisfy a centrally symmetrical relationship relative half the value of the length of the sequence: when λ is an optimum index, N-λ is also an optimum root index. For sequences with length Q²=N, the basic sequence formed through the optimum sequence can be used to form at least two other more optimum sequences through sign switching, conjugation and periodic modulation operations. The basic sequences can be assigned to different sectors of a base station.

EFFECT: high synchronisation accuracy.

33 cl, 11 dwg