Necessary and Sufficient Conditions of Channel Identifiability Based on Second-Order Cyclostationary Statistics

where h(.) is the channel impulse response; {Sk} and T are the information symbol sequence and symbol interval, respectively. The “blind” identification problem addressed in this paper i s the identifiability of a possibly nonmin imum phase channel h(.) given only the observation process .(a). The following assumptions are imposed to the above model: (1) { S k } is an i.i.d. sequence. (2) The symbol interval T is an integer. (3) The channel has a finite impulse response. (4) The noise process is uncorrelated with { S k } with known second-order statistics.