Patent ID: 7782756

Claim:
An apparatus (A) for generating sequences of signal coding elements for a signal transmission device (TD) on a code division multiple access communication network, said apparatus (A) comprising calculation means (CM) configured i) to construct a 2×2 intermediary matrix (M K ) with rank K, where K is a selected integer greater than or equal to 1, and comprising four matrix elements each constructed of another 2×2 intermediary matrix with rank K−1, then ii) to convert said 2×2 intermediary matrix (M K ) with rank K into an N×N final matrix (M′ K ) with rank K, where N=2 K , in which each element associated with one of the N rows and one of the N columns is a value, and iii) to deliver N sequences that are orthogonal to one another, each comprising N coding elements respectively constructed from the values of the elements contained within one of the N lines of said final matrix (M′ K ), and each capable of serving to spread signal spectra of signals, said signals being associated with different communication channels, before they are modulated and then transmitted, characterized in that said calculation means (CM) are configured to construct each intermediary matrix with rank K (M K ) using an odd-numbered value K and four matrix elements (X K , Y K , Z K , U K ) defined as follows: - X K = ( X K - 1 X K - 1 X K - 1 - X K - 1 ) , where X 1 =1, - Y K ⁡ ( Y K - 1 - Y K - 1 - Y K - 1 - Y K - 1 ) , where Y 1 =−1, - Z K = ( Z K - 1 - Z K - 1 - Z K - 1 - Z K - 1 ) , where Z 1 =1, and - U K = ( U K - 1 U K - 1 U K - 1 - U K - 1 ) , where U 1 =1.