Feedforward filter

A feedforward filter having a transfer function H(z) comprising:

• a signal divider having input signal X(z) and providing at its output signals mX(z) and nX(z), where m + n = 1;
• a first filter having an arbitrary transfer function G(z),
• said output mX(z) from said signal divider being input to said first filter,
• said first filter providing at its output the signal G(z)mX(z);
• first delay means having transfer function D.sub.1 (z),
• said output nX(z) from said signal divider being input to said first delay means,
• said first delay means providing at its output the signal D.sub.1 (z)nX(z);
• a second filter having transfer fucntion F(z),
• said output G(z)mX(z) from said first filter being input to said second filter,
• said second filter providing at its output the signal F(z)G(z)mX(z);
• a first mixer having input the signals F(z)G(z)mX(z) from said second filter and D.sub.1 (z)nX(z) from said first delay means and providing at its output one of the error signal .epsilon. = F(z)G(z)mX(z) .+-. D.sub.1 (z)nX(z);
• a third filter having transfer function K(z),
• said output .epsilon. from said first mixer being input to said third filter,
• said third filter providing at its output the signal K(z) .epsilon.;
• second delay means having transfer function D.sub.2 (z),
• said output G(z)mX(z) from said first filter being input to said second delay means,
• said second delay means providing at its output the signal D.sub.2 (z)G(z)mX(z);
• and
• a second mixer having input the signals D.sub.2 (z)G(z)mX(z) from said second delay means and K(z) .epsilon. from said third filter and providing at its output the signal Y(z) = H(z)X(z),
• said output signal Y(z) representing the convolution of said input signal X(z) and said transfer function H(z).