Patent ID: 6684234
Filing Date: 2004-01-27
Classification: H03H

Abstract:
A method for forming an output signal sequence y(nâˆ’p) from a digital input signal sequence x(n) and a reference sequence r(n) with adaptive filters, whereby a respective filter output signal that is optimally adapted to the respective filter reference signal is formed with the adaptive filters from a respective filter input signal and a respective filter output signal, comprising the steps of:forming the time functions x0&af;(t)=&Sum;n&it;x&af;(n)&CenterDot;Ï†&af;(t-n)&it;â€ƒ&it;and&it;â€ƒ&it;r0&af;(t)=&Sum;n&it;r&af;(n)&CenterDot;Ï†&af;(t-n)from the digital input signal sequence x(n) and the digital reference sequence r(n) with scaling functions Ï†&af;(t)=2&CenterDot;&Sum;n-1l=0&it;g&af;(l)&CenterDot;Ï†&af;(2-t-l);determining respective component sets dn1(x),dn2(x), . . . ,dnL(x) and cnL(x) and dn1(r),dn2(r), . . . ,dnL(r) and, cnL(r) of the discrete parameter wavelet transformation from said time functions with wavelet &varphi;&af;(t)=2&CenterDot;&Sum;Ï -1l=0&it;h&af;(l)&CenterDot;Ï†&af;(2&CenterDot;t-l),these being respectively applied in pairs to L+1 adaptive filters as a filter input and as a filter reference signal; andcombining the filter output signals of the adaptive filters dn1(y),dn2(y), . . . ,dnL(y) and cnL(y) to form a single output signal sequence y(nâˆ’p), with an operation inverse to the originally applied discrete parameter wavelet transformation, wherein: dnm(x)=DPWT(x,m,n) dnm(r)=DPWT(r,m,n) h(l)=(âˆ’1)lÂ·g(pâˆ’1âˆ’l) {overscore (g)}(l)=g(pâˆ’1âˆ’l) {overscore (h)}(l)=(âˆ’1)lâˆ’1Â·g(l) {overscore (h)}(l)=h(pâˆ’1âˆ’l) &Sum;Ï -1l=0&it;g2&af;(l)=&Sum;Ï -1l=0&it;h2&af;(l)=12,â€ƒ&it;and&Sum;Ï -1l=0&it;g&af;(t)&CenterDot;g&af;(l+2&CenterDot;k)=&Sum;Ï -1l+0&it;h&af;(l)&CenterDot;h&af;(l+2&CenterDot;k)=0&it;&LeftBracketingBar;for&it;â€ƒ&it;k=1,2,â€¦&it;â€ƒ,p-112&it;for&it;â€ƒ&it;k=0.