syntfil[CauerBOmega] - compute the new stopband frequency for the type B Cauer approximation
syntfil[CauerCOmega] - compute the new stopband frequency for the type C Cauer approximation
Calling sequence:
CauerBOmega(omega, omega_a)
CauerCOmega(omega_b, omega_zb)
Parameters:
omega - original stopband frequency
omega_a - magnitude of the transfer function's greatest zero for the type A Cauer approximation
omega_b - stopband frequency for the type B Cauer approximation
omega_zb - magnitude of characteristic function's least zeros for the type B Cauer approximation
Description:
Example:
> | with(syntfil): |
Original stopband frequency
> | Os:=1.2; |
Type A Cauer approximation
> | G[A],Phi[A],zeros[A]:=Cauer(4,Os,3,s); |
Type B Cauer approximation
> | G[B],Phi[B],zeros[B]:=CauerB(4,Os,3,s); |
Type C Cauer approximation
> | G[C],Phi[C],zeros[C]:=CauerC(4,Os,3,s); |
Greatest zero of transfer function
> | zeros[A][1]; |
New stopband frequency for type B
> | Os_b:=CauerBOmega(Os,Im(zeros[A][1])); |
Zeros of characteristic function for Cauer approximation of type B
> | [solve(numer(Phi[B]))]; |
New stopband frequency for type C
> | Os_c:=CauerCOmega(Os_b,.4490829917); |
Comparison of magnitude frequency response for Cauer approximation of type A , B a C
> | plot([MagnitudeHdB(1/G[A])(omega),MagnitudeHdB(1/G[B])(omega),MagnitudeHdB(1/G[C])(omega)],omega=0..2,-60..0,color=[red,green,blue]); |
See also:
Cauer, CauerB, CauerC, CauerPolesZeros, CauerBPolesZeros, CauerCPolesZeros