Channel equalizer and method for cancelling ghosts

In a communications system wherein an information signal is sent from a transmitter to a receiver via a communications channel having a responsive H(t) which includes minimum and maximum phase portions, wherein the information signal includes a training signal and data which experience ghosts as a result of the response H(t), wherein the training signal is representative of an impulse modified by transmitter-based processing circuitry having a response A(t) which also includes minimum and maximum phase portions, a receiver-based channel equalizer for removing ghosts experienced by the data, comprising:

• a filter chain receiving the transmitted training signal and its ghosts and the data and its ghosts, the filter chain including a plurality of cascaded, second order recursive filters, the first of which assumes and remains in a filter condition dependent on the training signal and its ghosts for outputting a modified signal, each successive filter assuming and remaining in a filter condition for outputting a modified signal dependent on the modified output of an immediately preceding filter so that when the data and its ghosts are received by the filter chain, each filter therein filters the data and its ghost according to its assumed condition, the assumed condition of each of said filters being such that the chain's cumulative response is the inverse of the result of convolving the minimum phase portion of H(t) with the minimum phase portion of A(t);
• and
• means for modifying the output of the filter chain by the minimum phase portion of response A(t) so that the training signal and data are recovered.