bp22nlp.mws

syntfil[BP22NLP] - frequency transformation from the symmetrical bandpass (BP) to the normalized lowpass (NLP) filter specification

Calling sequence:

      BP22NLP(fm, delta_fp, delta_fs, ap, as)

Parameters:

      fm       - passband geometric cetre  [Hz]

      delta_fp - passband width [Hz]

      delta_fs - stopband width [Hz]

  ap       - passband ripple [dB]

  as       - stopband attenuation [dB]

All parameters must be positive real values, where   delta_fp  < delta_fs   a   ap  < as .

Description:

  Os -  stopband frequency of normalized lowpass filter [1/s]

  ap -  passband ripple [dB]

  as -  stopband attenuation [dB]

Info level:

Setting of variable infolevel[syntfil]  can be used to get more detailed results.

infolevel[syntfil] =

      2  - print values f_s, f_p, fp, fs and specification of NLP (Os, ap, as)

      3  - as level 2 + print specification of entered BP (fm, delta_fp, delta_fs, ap, as) and plot BP filter specification

      4  - as level 3 + plot specification of NLP

Example:

>    with(syntfil):

`Syntfil version 1.53 loaded`

`You can set infolevel[syntfil] variable to 2..5 to get more detailed results!`

>    infolevel[syntfil]:=1;

infolevel[syntfil] := 1

>    x:=BP22NLP(1000,500,1000,3,40);

x := 1.999999998, 3, 40

>    infolevel[syntfil]:=4;

infolevel[syntfil] := 4

>    BP22NLP(1000,500,1000,3,40);

Filter specification:

fm = 1000.000000 Hz

delta_fp = 500.000000 Hz

delta_fs = 1000.000000 Hz

ap = 3.000000 dB

as = 40.000000 dB

f_s = 618.033988 Hz

f_p = 780.776406 Hz

fp = 1280.776406 Hz

fs = 1618.033988 Hz

[Maple Plot]

Specification of NLP:

Os = 2.000000 1/s

ap = 3.000000 dB

as = 40.000000 dB

[Maple Plot]

1.999999998, 3, 40

See also:

LP2NLP, HP2NLP, BP2NLP, BS2NLP

ButterworthNLPOrder, ChebyshevNLPOrder, CauerNLPOrder