Closed-form blind channel identification with MSK inputs

Blind equalization of non minimum phase FIR channels requires prior identification, for stability reasons. We present a novel algorithm able to identify a channel in presence of an unknown MSK modulated input (which can be viewed as an a approximation of the GMSK modulation used in GSM: mobile systems), by resorting: only to output second order moments. Blind identification is made, possible: because the: input is not; circular. It is shown that this approach reads to a system of L quadrics in L unknowns, if L denotes the number of taps of the unknown FIR channel. This system is then solved with the help of an original algorithm bast cl on resultant techniques. Performances in terms of Bit Error Rates are eventually reported.