elemslp.html

elemslp.mws

syntfil[ElemsLP] - transformation of the element values from the normalized lowpass (NLP) to lowpass (LP)

Calling sequence:

ElemsLP(blocks, R, fp)

Parameters:

blocks - table with NLP LC ladder description (see output from function DroppNLP)

R - value of terminating resistor [Ohm]

fp - LP cutoff frequency [Hz]

Parameters R a fp must be positive numbers.

Description:

This function returns table with LP filter description. The table has the same structure as input parameter blocks .

Index type is changed from LC_NLP_... to LC_LP_... .

The elements are transformed according to following rules:

Info level:

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

infolevel[syntfil] =

2 - print LP type, terminating resistors and LP LC ladder branches on separate lines with description.

Example:

> with(syntfil):

Table with NLP filter description

> elems_nlp:=table([
1 = table([Z = 1/(s*C1), elements = {C1 = 1.}, orientation = shunt]),
2 = table([Z = s*L1, elements = {L1 = 2.}, orientation = direct]),
3 = table([Z = 1/(s*C1), elements = {C1 = 1.}, orientation = shunt]),
R2 = 1.00, R1 = 1.00, type = LC_NLP_common]):

Parameters for transformation

> R,fp:=100,1000;

> elems_lp:=ElemsLP(elems_nlp,R,fp);

$elems_lp := TABLE([1 = TABLE([Z = 1/(s*C1), elements = {C1 = .1591549430e-5}, orientation = shunt]), 2 = TABLE([Z = s*L1, elements = {L1 = .3183098861e-1}, orientation = direct]), 3 = TABLE([Z = 1/(s*C...$
$elems_lp := TABLE([1 = TABLE([Z = 1/(s*C1), elements = {C1 = .1591549430e-5}, orientation = shunt]), 2 = TABLE([Z = s*L1, elements = {L1 = .3183098861e-1}, orientation = direct]), 3 = TABLE([Z = 1/(s*C...$
$elems_lp := TABLE([1 = TABLE([Z = 1/(s*C1), elements = {C1 = .1591549430e-5}, orientation = shunt]), 2 = TABLE([Z = s*L1, elements = {L1 = .3183098861e-1}, orientation = direct]), 3 = TABLE([Z = 1/(s*C...$
$elems_lp := TABLE([1 = TABLE([Z = 1/(s*C1), elements = {C1 = .1591549430e-5}, orientation = shunt]), 2 = TABLE([Z = s*L1, elements = {L1 = .3183098861e-1}, orientation = direct]), 3 = TABLE([Z = 1/(s*C...$
$elems_lp := TABLE([1 = TABLE([Z = 1/(s*C1), elements = {C1 = .1591549430e-5}, orientation = shunt]), 2 = TABLE([Z = s*L1, elements = {L1 = .3183098861e-1}, orientation = direct]), 3 = TABLE([Z = 1/(s*C...$

Compute transfer function from table with filter description

> h:=MakeH(elems_lp);

See also:

DroppNLP

ElemsHP, ElemsBP, ElemsBP2, ElemsBPm, ElemsBP2m, ElemsBS, ElemsBSm

MakeH, MakeRealL