Patent ID: 6738443
Filing Date: 2004-05-18
Classification: H04L

Abstract:
A method of generating a synchronization preamble signal for a Broadcast (BCCH) channel of an OFDM system, the method comprising the steps of:generating OFDM symbols by modulating the subcarriers Sâˆ’26,26 of the OFDM symbol as follows: Sâˆ’26,26={0,0,0,0,S1,0,0,0,S2,0,0,0,S3,0,0,0,S4,0,0,0,S5,0,0,0,S6,0,0,0,S7,0,0,0,S8,0,0,0,S9,0,0,0,S10,0,0,0,S11,0,0,0,S12,0,0,0,0); generating a time domain signal of the first part (A-FIELD) of the preamble signal by inverse Fast Fourier Transforming OFDM symbols; the preamble signal being characterized in that the frequency domain sequence S1 . . . S12 of the modulated subcarriers of the first part (A-FIELD) is: S1 . . . S12=+A,+A,+A,+A,+A,âˆ’A,âˆ’A,+A,+A,âˆ’A,+A,âˆ’A; S1 . . . S12=+A,+A,+A,+A,âˆ’A,âˆ’A,+A,+A,âˆ’A,+A,âˆ’A,+A; S1 . . . S12=+A,+B,âˆ’A,âˆ’B,âˆ’A,âˆ’B,âˆ’A,âˆ’B,âˆ’A,+B,+A,âˆ’B; S1 . . . S12=+A,+B,âˆ’A,âˆ’B,+A,âˆ’B,+A,âˆ’B,+A,âˆ’B,âˆ’A,+B; S1 . . . S12=+A,âˆ’B,âˆ’A,+B,âˆ’A,+B,âˆ’A,+B,âˆ’A,âˆ’B,+A,+B; S1 . . . S12=+A,âˆ’B,âˆ’A,+B,+A,+B,+A,+B,+A,+B,âˆ’A,âˆ’B; or an order reversed modification thereof in which the values of S1 to S6 are swapped with S12 to S7, respectively, such that S1 is replaced by S12, S2 is replaced by S11, . . . , and S12 is replaced by S1, wherein: â€ƒA=exp(j*2*&pgr;*&phgr;A),B=A*exp(j*&pgr;/2), and 0&lE;&phgr;A&lE;1.