A multistep linear prediction approach to blind asynchronous CDMA channel estimation and equalization

A multistep linear prediction approach is presented for blind channel estim ation, multiuser interference (MUI) suppression, and detection of asynchron ous short-code direct sequence code division multiple access signals in mul tipath channels, Only the spreading code of the desired user is assumed to be known; its transmission delay may be unknown. We exploit the recently pr oposed multistep linear prediction approach for blind multiple-input multip le-output channel estimation in conjunction with the structure imposed by t he desired user's spreading code sequence. With the knowledge of the desire d user's code sequence, only the second-order statistics of the data are ne eded under certain sufficient conditions on the underlying multiuser MIMO t ransfer function. Based on the desired user's channel estimate, a linear mi nimum mean square error filter is designed for simultaneous equalization an d MUI suppression. Three illustrative simulation examples are presented.