Patent ID: 7729438

Claim:
A method of data communication in a wireless system, comprising: parsing a bit stream into multiple spatial data streams; interleaving the bits in each spatial data stream by performing multiple column rotations and at least one row rotation, to increase diversity of the wireless system; and transmitting the bits of each spatial data stream, wherein the interleaving the bits in each spatial data stream includes performing a first interleaving permutation to ensure that adjacent coded bits are mapped onto nonadjacent subcarriers in one data stream for transmission, the first interleaving permutation varying on different spatial data streams by performing the different multiple column rotations and the at least one row rotation, to increase diversity of the wireless system, and wherein each spatial data stream interleaver array includes N row rows and N col columns of bits, such that the number of row and column rotations for each spatial data stream is according to the relation: i=N row *((( k mod N col )+floor( N col /N ss )* i ss )mod N col )+(floor( k/N col )+ ceil ( N/N ss *i ss )* N BPSC )mod N row where k=0, 1, . . . N CBPS −1, i ss =0 . . . N−1 where N ss is the number of spatial data streams, N BPSC is the number of coded bits per subcarrier, N CBPS is the number of coded bits in a single OFDM symbol, i is the index of the bits after the block interleaving, k is the index of the coded bit before the first interleaving permutation, N ss is the number of spatial data streams and i ss is the index of spatial data stream, and N=3 for 20 MHz channel and N=6 for 40 MHz channel.