Patent ID: 7859987

Claim:
A method of data communication in a wireless system, comprising the steps of: parsing a bit stream into multiple spatial data streams; interleaving the bits in each of one or more spatial data streams by performing frequency rotation after an interleaving operation, to increase diversity of the wireless system, wherein frequency rotation is performed according to relation: r =( j −((2× i ss )mod 3+3×floor( i ss /3))× N rot ×N BPSC )mod N CBPS , j= 0, 1, . . . , N CBPS −1, wherein N BPSC is the number of coded bits per subcarrier, N CBPS is a block size corresponding to a number of coded bits in a single Orthogonal Frequency Division Multiplexing (OFDM) symbol, j is an index after a second permutation and before a third permutation, r is an index after the third permutation, i SS =0, 1, . . . , N SS −1 is the index of the spatial stream on which interleaving is operating, N ss is the number of spatial streams, and N rot is a base rotation number in use and transmitting the bits of each spatial data stream.