Orthogonal complex-valued spreading sequences with a wide range of correlation properties

A new family of complex-valued spreading sequences was proposed for code-division multiple-access (CDMA) systems by Oppermann and Vucetic (1994, 1997), which offer the system designer the choice of a wide range of correlation properties. This letter identifies a subfamily of spreading sequences for use in CDMA systems in which the sequence elements in any set are orthogonal. The subfamily also offers a very wide range of values for both aperiodic auto-correlation (AC) and aperiodic cross-correlation (CC) functions with the added property of having orthogonal elements.