Patent ID: 8270551

Claim:
A method for synchronising a device for receiving scrambled data, the method comprising: receiving scrambled data that has been scrambled by at least one periodic scrambling sequence organized into K time intervals, each including N periods of bits called symbols; and calculating a synchronization value of at least one generator polynomial of said scrambling sequence, in a predetermined synchronization time and synchronization bit period, wherein, in said calculation step, a matrix calculation of said synchronization value is implemented that operates successively: a jump of at least one time interval inside said sequence, in order to position on a desired time interval; and a jump of at least one bit period inside said desired time interval, in order to position on a desired bit period wherein said data is scrambled according to at least two scrambling sequences X and Y, wherein an initialization value for said sequence Y is set and an initialization value for said sequence X is characteristic of a device for transmission of said scrambled data, and wherein, to reach an index phase vector (β+μ) from an index phase vector β of said scrambling sequence by successive jumps of value i, at least the following series of steps is carried out: breaking down the index value μ in the form of a sum of the quotient and the remainder r of the Euclidian division of μ by i, said quotient being expressed in the form of a product of an integer j with said jump value i; increasing to the integer power j said time interval transfer matrix of said sequence X, said time interval including ranges of i bit periods; multiplying said index phase vector β by said time interval transfer matrix (M X i ) j , so as to obtain the value of said index phase vector (β+i×j), then; multiplying said index phase vector (β+i×j) by said bit period transfer matrix (M X r ), so as to be positioned on the correct bit period value; so as to be limited to a value of (j+r) the number of clock cycles to be applied in order to reach said desired index phase vector (β+μ).