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dfilt.parallel

Discrete-time, parallel structure filter

Syntax

Hd = dfilt.parallel(Hd1,Hd2,...)

Description

Hd = dfilt.parallel(Hd1,Hd2,...) returns a discrete-time filter, Hd, which is a structure of two or more dfilt filters, Hd1, Hd2, etc. arranged in parallel. Each filter in a parallel structure is a separate stage. You can display states for individual stages only. To view the states of a stage use

Hd.stage(1).states

To append a filter (Hd1) onto an existing parallel filter (Hd), use

addstage(Hd,Hd1)

You can also use the nondot notation format for calling a parallel structure.

parallel(Hd1,Hd2,...)

Examples

Using a parallel structure, create a coupled-allpass decomposition of a 7th order lowpass digital, elliptic filter with a normalized cutoff frequency of 0.5, 1 decibel of peak-to-peak ripple and a minimum stopband attenuation of 40 decibels.

k1 = [-0.0154    0.9846   -0.3048    0.5601]; 
Hd1 = dfilt.latticeallpass(k1);
k2 = [-0.1294    0.8341   -0.4165];
Hd2 = dfilt.latticeallpass(k2);
Hpar = parallel(Hd1 ,Hd2);
gain = dfilt.scalar(0.5);    % Normalize passband gain
Hcas = cascade(gain,Hpar);

For details on the stages of this filter, use

info(Hcas.Stage(1))

and

info(Hcas.Stage(2))

Version History

Introduced before R2006a