Patent ID: 7590044

Claim:
A method for an interleaver within an encoder to encode information bits, the method comprising the steps of: the interleaver grouping the information bits into couples (A 0 ,B 0 ), (A 1 ,B 1 ), (A 2 ,B 2 ), (A 3 ,B 3 ), . . . , (AN−1,BN−1); the encoder performing the steps of: encoding (A 0 ,B 0 ), (A 1 ,B 1 ), (A 2 ,B 2 ), (A 3 ,B 3 ), . . . , (AN−1,BN−1) in a first encoder; switching alternate couples to produce (A 0 ,B 0 ), (B 1 ,A 1 ), (A 2 ,B 2 ), . . . , (BN−1, AN−1)=u 1 ( 0 ), u 1 ( 1 ), u 1 ( 2 ), u 1 ( 3 ), . . . , u 1 (N−1); mapping the couples of sequence u 1 onto an address j of an interleaved sequence, where a function P(j) provides the address of the couple of the sequence u 1 that shall be mapped onto the address j of the interleaved sequence, wherein u 2 ( j )=u 1 (P(j))=[u 1 (P( 0 )), u 1 (P( 1 )), u 1 (P( 2 )), u 1 (P( 3 )), . . . , u 1 (P(N−1))], and wherein for j=0, . . . , N−1 switch j mod 4: case 0: P(j)=(P 0 j+1)mod N case 1: P(j)=(P 0 j+1+N/2+P 1 )mod N case 2: P(j)=(P 0 j/+1+P 2 )mod N case 3: P(j)=(P 0 j+1+N/2+P 3 )mod N; encoding u 2 in a second encoder; transmitting the encoded u 1 and/or u 2 ; and where values for N, P 0 , P 1 , P 2 , and P 3 take the form Data block size (bytes) N P 0 P 1 P 2 P 3 120 480 53 62 12 2 240 960 43 64 300 824 360 1440 43 720 360 540 480 1920 31 8 24 16 600 2400 53 66 24 2 and wherein (A 0 ,B 0 ), (A 1 ,B 1 ), (A 2 ,B 2 ), (A 3 ,B 3 ), . . . , (AN−1,BN−1) are information couples, N is an integer, and P( 0 ) . . . P(N−1) are functions that provide the address of the couples.